Asphalt Mixing Plant

Asphalt Mix Design and Field Control 2

2011-06-18T06:57:00.000-07:00

It has continued been accustomed that arrangement of the accumulated is one of the factors that charge be anxiously advised in the architecture of city paving mixtures, abnormally for abundant assignment highways. The purpose in establishing and authoritative accumulated arrangement is to board acceptable voids in the city accumulated admixture to board the able city blur array on anniversary atom and board the architecture air abandoned arrangement to acquiesce for thermal amplification of the city aural the mix. Minimum voids in the mineral accumulated (VMA) requirements accept been accustomed and alter with the top accumulated size.

Traditionally, arrangement requirements are so ample that they admittance the use of paving mixtures alignment from base to accomplished and to either low or aerial stability. To added complicate matters, altered combinations of clarify sizes are defined to ascendancy specific allocation ranges. Standardization of clarify sizes and accumulated gradations, which has generally been suggested, is not acceptable to action because of the convenance of application locally accessible abstracts to the admeasurement possible.

In the aboriginal 1960's, the Bureau of Public Roads alien a arrangement blueprint (Figure 1) which is abnormally advantageous in evaluating accumulated gradations. The blueprint uses a accumbent calibration which represents clarify admeasurement openings in microns aloft to the 0.45 ability and a vertical calibration in percent passing. The advantage in application this blueprint is that, for all applied purposes, all beeline ambit advised from the lower larboard bend of the chart, advancement and against the appropriate to any specific nominal best atom size, represent best body gradations.
The nominal best atom clarify admeasurement is the better clarify admeasurement listed in the applicative blueprint aloft which any actual is acceptable to be retained. An archetype is apparent in Figure 2.

The gradations depicted in Figures 3 and 4 are abstract to allegorize the credibility actuality made. By application the chart, accumulated gradations can be accompanying to best body arrangement and acclimated to adumbrate if the admixture will be accomplished or base textured as apparent in Figure 3.

Soon afterwards the blueprint was developed, it was acclimated to abstraction gradations of accumulated from several mixtures that had been appear as accepting unsatisfactory compaction characteristics. These mixtures could not be compacted in the accustomed address because they were apathetic in developing acceptable adherence to bear the weight of the rolling equipment. Such mixtures can be alleged "tender mixes." This abstraction articular a constant arrangement arrangement in these mixes as is illustrated in Figure 4.

Most notable is the bulge in the ambit abreast the #40 clarify and the collapsed abruptness amid the #40 clarify and the #8 sieve. This indicates a absence of actual in the #40 to #8 clarify ambit and an balance of actual casual the #40 sieve. Mixtures with an accumulated announcement this arrangement appropriate are affected to actuality tender, decidedly if the fines are composed of accustomed sand.

As allotment of the bituminous mix architecture process, the accumulated arrangement should be advised on the 0.45 ability arrangement chart

Asphalt Mix Design and Field Control

2011-06-18T01:46:00.000-07:00

1.PURPOSE.
To set forth guidance and recommendations relating to asphalt concrete paving, covering the areas of materials selection, mixture design, and mixture production and placement. The procedures and practices outlined in the Technical Advisory (TA) are directed primarily towards developing quality asphalt concrete pavements for high-type facilities. The TA can also be used as a general guide for low-volume facilities.
2.CANCELLATION.
Federal Highway Administration (FHWA) Technical Advisory T 5040.24, Bituminous Mix Design and Field Control, dated August 22, 1985, is canceled.
3.BACKGROUND
1.Over one-half of the Interstate System and 70 percent of all highways are paved with hot-mix asphalt concrete. Asphalt concrete is probably the largest single highway program investment today and there is no evidence that this will change in the near future. However, there is evidence that the number of premature distresses in the nation's recently constructed asphalt pavements is increasing. Heavier truck axle weights, increased tire pressures, and inadequate drainage are some of the factors leading to the increase in premature distress. The FHWA has been concerned with the deterioration in quality of asphalt concrete pavements for many years and in 1987 a special FHWA Ad Hoc Task Force studied two of the most common distresses existing today and subsequently issued a report titled "Asphalt Pavement Rutting and Stripping." The report contained both short-term and long-term recommendations for improving the quality of asphalt pavements.
2. With the variables of environment, component materials, and traffic loadings found throughout the United States, it is not surprising that there are many State-to-State or regional variations of design and construction requirements. No one set of specifications can achieve the same results in all States because of the factors mentioned above. However, there are many things that States can do to improve their current mix design and field control procedures to ensure that quality asphalt pavements will be constructed. This TA incorporates many of the FHWA Task Force recommendations and presents the current state-of-the-art in materials, mix design, plant operation, laydown and compaction, and other areas relating to quality hot-mix asphalt pavements.
4.MATERIALS
1.Aggregate is the granular material used in asphalt concrete mixtures which make up 90-95 percent of the mixture weight and provides most of the load bearing characteristics of the mix. Therefore, the quality and physical properties of the aggregates are critical to the pavement performance. The following is recommended:
2.Asphalt grade and characteristics are critical to the performance of the asphalt pavement. The following is recommended:
5.MIX DESIGN
1.Asphalt concrete mixes should be designed to meet the necessary criteria based on type of roadway, traffic volumes, intended use, i.e., overlay on rigid or flexible pavements, and the season of the year the construction would be performed. Each State's mix design criteria should be as follows.

2.* Equivalent Single Axle Load
3.MINIMUM PERCENT VOIDS IN MINERAL AGGREGATE (VMA)

4.Standard mix design procedures (Marshall, Hveem) have been developed and adopted by AASHTO, however, some States have modified these procedures for their own use. Any modification from the standard procedure should be supported by correlation testing for reasonable conformity to the design values obtained using the standard mix design procedures.
5.Stripping in the asphalt pavements is not a new phenomenon, although the attention to it has intensified in recent years. Moisture susceptibility testing should be a part of every State's mix design procedure. The "Effect of Zero on Compacted Bituminous Mixtures" (immersion compression test) (AASHTO T-165) and "Resistance of Compacted Bituminous Mixture to Moisture Induced Damage" (AASHTO T-283) are currently the only stripping test procedures which have been adopted by AASHTO. The AASHTO T-283, commonly known as the Lottman Test, requires that the test specimens be compacted so as to have an air void content of 7 ± 1 percent, while AASHTO T-165 does not. This air void content is what one would expect in the mat after construction compaction. There is considerable research underway on developing better tests for determining moisture damage susceptibility of the aggregate asphalt mixtures. One of the most promising test procedures is that developed by Tunnicliff and Root as reported in the National Cooperative Highway Research Program (NCHRP) Report 274. This test is similar to AASHTO T-283, but it takes less time to perform. In the majority of cases hydrated lime and Portland cement have proven to be the most effective antistripping additives.
6.The determination of air voids in the laboratory mix is a critical step in designing and controlling asphalt hot-mix. In order to determine air voids, the theoretical maximum density or the maximum specific gravity of the mix must be determined. This can be accomplished by using the "Maximum Specific Gravity of Bituminous Paving Mixtures" (Rice Vacuum Saturation) (AASHTO T-209).
7.Proper mix design procedures require that each mix be designed using all of the actual ingredient materials including all additives which will be used on the project.
8.The complete information on the mix design should be sent to the plant. The following information should be included in the mix design report and sent to the plant.
9.Formal procedures should be established to require that changes to mix designs be approved by the same personnel or office that developed the original mix design.
10.After startup, the resulting mixture should be tested to verify that it meets all of the design criteria.
6.PLANT OPERATIONS
1.In order to assure proper operation, an asphalt plant must be calibrated and inspected. Plant approval should be required and should cover each item on the asphalt plant checklist (Attachment 3).
2.To avoid or mitigate unburned fuel oil contamination of the asphalt mixture, the use of propane, butane, natural gas, coal or No. 1 or No. 2 fuel oils is recommended.
3.If the asphalt cement is overheated or otherwise aged excessively, the viscosity of the recovered asphalt will exceed that of the original asphalt by more than four times. However, if the viscosity of the recovered asphalt is less or even equal to the original viscosity, it has probably been contaminated with unburned fuel oil.
4.For drum mixer and screenless batch plants there should be three separate graded stockpiles for surface courses and four for binder and base courses. Each stockpile should contain between 15 to 50 percent by weight of the aggregate size in the mix design. The plus #4 sieve aggregate stockpile should be constructed in lifts not exceeding 3 feet to a maximum height of 12 feet. There should be enough material in the stockpiles for at least 5 days of production. The plant should be equipped with a minimum of four cold feed bins with positive separation.
5.Control testing of gradation and asphalt content should be conducted to assure a quality and consistent mixture. In many States, the contractor or supplier is required to do this testing.
6.Acceptance testing should be conducted for gradation and asphalt content of the final mixture.
7.The plotting of control and acceptance test results for gradation, asphalt content, and density on control charts at the plant provides for easy and effective analysis of test results and plant control.
8.The moisture content of the aggregate must be determined for proper control of drum mixer plants. The asphalt content is determined by the total weight of the material that passes over the weigh bridge with the correction made for moisture. Sufficient aggregate moisture contents need to be performed throughout the day to avoid deviations in the desired asphalt content.
9.Moisture contents of asphalt mixtures is also important. The extraction and nuclear asphalt content gauge procedures will count moisture as asphalt. For this reason, a moisture correction should be made. In addition, high moisture contents in asphalt mixtures can lead to compaction difficulty due to the cooling of the mix caused by evaporation of the moisture. This is particularly important with drum mixer mixes which require moisture for the mixing process. Some States specify a maximum moisture content behind the paver. A recommended maximum moisture content behind the paver is 0.5 percent.
7.LAYDOWN AND COMPACTION
1.Prior to paving startup, equipment should be checked to assure its suitability and proper function. Project equipment approval should include the items shown on the project inspection checklist (Attachment 4).
2.Paving startup should begin with a test strip section. This will allow for minor problems to be solved, establishment of roller patterns and number of passes, and will assure that proper placement and compaction can be attained.
3.In order to assure proper placement and compaction, it is essential that the mat be placed hot. Establishment of and compliance with the following items should be included: minimum mix, underlying pavement, and ambient temperatures. Cold weather and early or late season paving should be avoided. The practice of raising the temperature of the mixture to combat the cold conditions should not be permitted, as this will contribute to excessive aging of the asphalt cement.
4.The use of a pneumatic roller in the compaction process is strongly encouraged. When used in the intermediate rolling it will knead and seal the mat surface and aid in preventing the intrusion of surface water into the pavement layers. It will also contribute to the compaction of the mat.
5.Density requirements should be established to result in an air void system in the mat of 6-8 percent immediately after construction. This allows for the inherent additional densification under traffic to an ultimate air void content of about 3-5 percent. Density acceptance specifications should require a percentage of maximum density as determined by AASHTO T-209. A percentage of test strip density or Marshall laboratory density can be used provided each is related to the maximum density. The specified density should be attained before the mat temperature drops below 175° F.
6.Density measurement should be accurate, taken frequently, and the results made available quickly for each day of production. Density should be determined by test cores, or by properly calibrated nuclear test gauges. Specifications should require several tests to be averaged to determine density results for acceptance.
7.Successive hot-mix courses should not be placed while previous layers are wet. To avoid, or minimize the penetration of water into base and binder courses, paving operations should be scheduled so that the surface layer(s) is placed within a reasonable period after these courses are constructed. To the greatest extent possible, construction should be planned to avoid the necessity of leaving layers uncovered during wet seasons of the year.
8.MISCELLANEOUS
1.Some States have established procedures to accept out-of-specification material and pavement with a reduction in price. These procedures include definition of lot size/ production time, tolerances, and pay factor reductions for ingredient materials, combined mixture properties, pavement density, pavement smoothness, and lift thickness.
2.Prior to the start of production and placement operations, a preplacement conference, including all the paving participants, should be held. This conference would define duties and responsibilities for each phase of the operation as well as problem-solving procedures.
3.During startup it is very effective to have a construction and/or materials specialist at the project site to assist in identifying and solving any problem that develops.
4.Because asphalt hot-mix pavement construction is complex, it requires that each person involved understand his/her function thoroughly. It is also helpful if each person has a basic understanding of each of the many phases involved. It is recommended that States develop or use existing training to address these phases of asphalt paving.

Source :
Ronald E. Heinz
Associate Administrator for
Engineering and Program Development
http://www.fhwa.dot.gov/pavement/

Vibrating Screen Guideline

2011-06-17T07:27:00.000-07:00

Here I want give guidelines about vibrating screen due to Vibrating screen Manufacturers Association. It Describes the exact reasons why for all of the important elements required to be taken into consideration when designing a vibrating screen.
Here the steps :
1.Determine what needs to be screened: about the material, weight , tons per hour, max in feed size, product size wanted
2.This will give you base data to do a mathematic vibrating screen sizing (standard formula) to determine the size of the vibrating screen needed in square feet to do the job.
3.You must cross check the BED DEPTH to decide if it meets the guidelines of VSMA. This will either leave the size the same or require you to UPSIZE the machine footage to meet the bed depth needs. In other words, we DO NOT want to have 6" of material bed depth or mat at the end of the machine length for example on a 1/2" opening. This would result in carryover. RULE of thumb: WIDTH = More TPH and LENGTH = more clean or efficient screening
4.I have a chart of SPEED STROKE SLOPE ideal combinations for different screen clohth openings for both INCLINED circle throw type machines that use 20 degree incline or gravity to help the foot travel of the material on the deck. This chart also covers FLAT or horizontal screens to identify the proper setup to screen at various openings. Rule of thumb: The stroke or eccentricity must be large enough always to CLEAR the TOP DECK openings first or nothing gets thru and nothing happens or in other words = ZERO SCREENING EFFICIENCY. The assumed efficiency of screening calculations is always 95% efficiency on top deck, and declines for the lower decks on the same machine
5.Some typical SPEED STROKE SLOPE COMBOS for a 2 bearing free floating circle throw vibrating screen. We basically want to stay within 3.5 to 4.g's accelerating force to allow for efficient vibrating forces to actually screen good and not have the machine fly apart by operating at too high an accelerating force. This range of accelerating force basically refers to INCLINED CIRCLE THROW MACHINES working in the -3" +10mesh ranges
OPG: +1" -3": need 3/8" circle, 850rpm, 18-25 deg range
- 1"+4mesh: need 5/16" circle, 900rpm, 18-25 deg range
-1/2"+10mesh need 1/4" circle, 1000rpm 18-25 deg range

Typical install angle is 20 degree and if material is non free flowing then, we make the angle either variable if on a portable screening plant or steeper if on a stationary plant. Typical FPM IN THE 60-75 FPM range.
6.The finer the screening the smaller the eccentric slope needed to stratify the coarse fractions and the faster the rpm is needed to make more introductions to the cloth openings. For very fine screening we go to 45 deg slope availability with a pin prick or very tiny 1/32" or smaller eccentric stroke with many different types of vibrating equipment specially designed to specifically handle these fine cuts.
7.HORIZONTAL SCREENS: Run at higher G forces due to the fact we do not have MOTHER nature or gravity to help us with the FOOT TRAVEL rate OR FOOT PER MIN. (FPM) On a horizontal the typical fpm is 45 FPM.
8.Once we build the vibrating screen, with all the bells and whistles on it..........ie.....thicker liner plates, heavier than normal wirecloth, extended lips, heavy rubber vs wire cloth and take all the static weight into consideration - we now design the shaft and the eccentric offset to accomodate moving that static weight at the desired stroke or eccentric offset. The counterweights are typically a solid engineered mass that would have bolted on flywheel weights. These weights differ by manufacturer model.
9.But, for example: It is not unusual for the flywheel to have three 1/2" plate weights bolted onto each wheel on the heavy side or six oclock position of the wheel. This would basically give us the largest stroke or circle you could get on the vibrating body. IE: 3/8" circle at 840 rpm. If i took 1 of plate weights off both wheels - it may reduce the stroke or circle size to 5/16" circle and then I would and could increase the speed of the motor sheave to run at 900 rpm, and if I took all the weights off the wheel completely - it may give me 1/4" circle which i could then speed up the machine to 1000 rpm by the rules of VSMA. RULE OF THUMB: always do 2 things..........not one. If you change stroke you should normally always change the speed. If i just sped up a unit that had a 3/8" circle size to 1000 RPM.......the accelerating forces would be way over the design factor and the sideplates and bearings would crack out or self destruct the machine.

Tons of Asphalt for GFIP

2011-01-29T05:54:00.000-08:00

Hot and cold asphalt manufacturer Much Asphalt supplied over 1,1- million tons of asphalt over 30 months, ending in October, to the South African National Roads Agency Limited’s Gauteng Freeway Improvement Project (GFIP).

When the company completes its supply contracts for the GFIP in September 2011, Much Asphalt will have supplied asphalt worth more than R1-billion to the project.

“No other asphalt supplier in South Africa could have achieved what we did in the past two years. Through significant investments in people, plant capacity and quality control systems, we have been able to supply 15 joint venture contractors on various GFIP sites by deadline. With equally challenging supply projects, such as the N1, also under way in the Western Cape, we had to ensure that we provided equal and adequate focus in both regions,” says Much Asphalt marketing director John Onraët.

The company had to overcome a number of challenges to provide the large quantities required for the GFIP on time and to specification. Significant challenges included the continuity of raw materials supply, delivery logistics, the potential delays caused by bad weather, the possible increase in demand, the risk of experiencing problems with products, mixing plant availability and continuity of supply to other clients.

Much Asphalt believes that efficient project management is essential for its seven plants in Gauteng and the neighbouring provinces, with a combined capacity of 1 100 t/h, which are involved in supplying the GFIP.
Leadership was a priority at the outset of the GFIP contracts, with a steering committee assembled to lead the project. Dedicated contracts managers were given responsibility for regular shifts, as well as additional shifts during peak demand times, while a logistics manager was appointed to focus exclusively on deliveries from Much Asphalt’s plants to the GFIP sites.

Daily shifts were increased from two to three at all seven plants and included two production shifts and a plant maintenance shift. This was important in reducing plant breakdowns and ensuring consistent product quality and meeting demand from the GFIP, as well as demand from other clients. Some downtime was experienced during peak demand periods, but was mitigated by rerouting and rescheduling plant supplies.

Continuous communication about progress and quality is ongoing and includes daily meetings with the contractors and consulting engineers.

Much Asphalt says that strong long-term relationships with suppliers have resulted in few delays caused by material supply issues on the GFIP.

“The company ensures that it replaces outgoing product with raw material daily. Constant contact with the refineries is key to ensuring that the bitumen supply is managed, as well as with sand and aggregates, and fuel and binder suppliers,” adds the company.

Further, Much Asphalt’s process control laboratories went into overdrive when undertaking quality testing of both raw materials and finished products for the GFIP.

“It has been difficult to keep up with the quality of incoming aggregates, owing to the sheer volumes arriving at the mixing plants, but interlaboratory comparisons and constant calibration have helped to ensure consistency.

“Through dedicated leadership, good relationships with suppliers and clients and constant attention to product quality, we are confident that we will complete our GFIP commitments successfully and on time,” concludes Onraët.

By John Onra ; Process Controller

Coal Fired Asphalt Plant

2011-01-29T05:11:00.000-08:00

The invention comprises a coal-fired burner system for use in a drum mix asphalt plant or drum dryer used for producing asphalt paving composition.
Coal to fire the burner is ground to a -200 mesh size by an air-swept rotary impact mill, and a classifier at the exit from the mill controls the size of the particles leaving the mill.
The pulverized coal particles are recovered from the exhaust airflow exiting the mill by a fiber filter collector and temporarily stored in a small surge bin.
Coal is metered from the surge bin into a primary air conduit leading to the burner.

The availability of a small but ready supply of coal in the surge bin provides quick response to a need for increased coal while avoiding the dangerous storage of large quantities of pulverized coal dust. As the weight of coal dust in the surge bin decreases, control circuitry provides for the processing of additional coal to maintain a ready supply of processed coal in the surge bin.

Use of a burner having swirl vanes to create a short cyclonic flame pattern permits the burner to be mounted directly in the upper end of the drum without the need for a separate combustion chamber, but without sending a long flame into the mixing area of the drum where liquid asphalt is introduced, which would cause a fire hazard and pollution problem.

United States Patent 4638747

Alternative Energy From N-viro Techology

2010-03-31T05:48:00.000-07:00

N-Viro International Corporation,
located in Daytona Florida, and Toledo Ohio USA develops and licenses its technology to municipalities and private companies.
The N-Viro technologies involve the mixing of municipal bio solids with specific alkaline waste products from the coal combustion electric generation, cement and lime industries. This process stabilizes organic waste thru pasteurization and complete disinfection.
I call this a green technology,
Waste to energy is a future Renewable energy that can replace the fosil energy that have used by people arround the world in nowadays.
Asphalt Mixing Plant uses coal in combustion Process , coal can involve a bad air polution.
But with clean coal from N-Viro Technology , this problem will be minimized even eliminated.
So lets save the world by using the opportunity fuels ,enviromental energy for our offspring
Please Visit N-Viro International Corporation

Modified Marshal Characteristic Of Dense Graded Asphalt Emulsion Mixes

2010-03-01T18:43:00.000-08:00

Growth in the use of asphalt emulsions was relatively slow, and limited by the type of asphalt emulsions availability and a lack of knowledge as to how they should be used. continuing equipment of new types and grades of asphalt emulsion, coupled with improved construction equipment and practices now give a broad range of choices, with which virtually any roadway requirement can be fulfilled. Wise selection and use of an appropriate asphalt emulsion can yield significant economic profits.

This thesis describes an investigation of the characteristics of an asphalt emulsion mix comprising a dense graded aggregate and a slow-setting cationic emulsion. The Marshall procedure was modified to evaluate the strength and deformation characteristics, of the mix; samples were listed in the dry condition at 35 Celcius degree. The influence of curing period on these two parameters was also researched.

Preliminary tests showed that the aggregate and emulsion were compatihle and indicated a suitable premix water content. Tests indicated that there is an optimum compaction water content tor maximum modified Marshall stability, and this parameter is a function of curing period. Measurement of strength and deformation made on specimens prepared at various asphalt emulsion contents indicated the following trends :

-Modified Marshall stability decreases with increase in residual asphalt content.

-Dry density decreases with increase in residual asphalt content.

-The modified Marshall flow generally decreases to a minimum value with increase in residual asphalt content.

-At any residual asphalt content, modified Marshall stability, Marshall quotient, and dry density generally increase with increase in curing time.

Information Dissemination Right @2008 ITB Central Library
By :Sigit Subroto (NIM :269 95 012), S2

Gasification Technology For Coal Burner

2010-02-23T19:01:00.000-08:00

All of the industries want a pollution-free technology and effective cost for operational.
Tools gasification with chemical-physical reactions separating the components of coal that can not burn and turn coal into fuel gas with high efficiency and clean,
so users will have a clean combustion systems with energy supply system is not expensive, so the operational cost in the company will be more saved.
Gasification technology excellences :
a. Replace the expensive fuel oil or electricity with the cheap coal.
Based on the data usage on client gasification that already using this technology, operating costs can be reduced to 3 to 4 times more efficient.
b. Clean environment
Produce a clean coal combustion and can meet the standards of environmental protection without any dust collector or desulfurisasi units, the density of smoke and dust emissions from the kiln and boiler units is less than 80mg/Nm3, the density of sulfur dioxide emissions of less than 800mg/Nm3.
c. Energy saving and consumption reduction
Several types of clients that have been changed by using the gasification gas, can increase its thermal efficiency of about 15-30% when compared with the use of coal combustion in a direct and more efficient electricity consumption, for about 20-40%. For new boiler is not require a large chimney if they usie coal gasification.
d. easy and safe machines.
With the complete Atmospheric Water Jacket on the reactor body makes operation more easy.
Accordance with the follows factory :

- Plant food

- Plant fertilizer

- Printing can

- Drying of wood

- Melting brass

- Etc.

Quality Improvement Of Asphaltic Concrete Mixture (AC Type) With Variation Of Aggregates

2010-02-22T19:26:00.000-08:00

The use of local aggregate is preferable to make the Asphaltic Concrete, AC type, as wearing course for highway pavement.
This is because it is more economical to use the local aggregate as much as possible. Up to now in Barito Selatan, Central Kalimantan,Indonesia.
Aggregates for Hot Mix Asphalt (HMA) have to be imported from Barabai, South Kalimantan, about 200 km distance from Buntok city, from which the aggregate arc considered meeting the required specification.
In the south Barito , however the natural source of local aggregates is actually available; the coarse aggregates arc found in Karau river at Awang village, gravel and sandstone arc found in Barito river and limestone boulder arc available at Sibung village. Unfortunately, these local aggregate arc never tested before for their characteristic performance,
so that local contractors arc still importing their aggregates from Barabai. This investigation is performed to test the characteristic performance of local aggregate of south Barito, included abration test, affinity for asphalt, water absorption and specific gravity of aggregate.
It is found that the local aggregate has met the specification, except abration of the local limestone, which is over than 40%, so that the limestone is not to be used as coarse aggregate.
In this study, the aggregate mixture containing crushed gravel from Awang village, natural gravel and sand from Barito river, added by mineral filler of limestone, can be designed to meet the number V gradation type of SNI 1737 - 1989-F as recommendation.

To improve Asphaltic Concrete (AC type) in quality and cost, the local aggregates are mixed with aggregates from Barabai in six variation and tested with Marshall for heavy traffic requirement (75 blows). The variation mixture of aggregate arc: Variation I for 100% local aggregate mixture, Variation 2 for 100% aggregate mixture from Barabai, Variation 3 for mixture of 75% local sand and gravel + 25% aggregate from Barabai, Variation 4 for mixture of 50% local sand and gravel + 50% aggregate from Barabai, Variation 5 for mixture of 25% local sand and gravel + 75% aggregate from Barabai and Variation 6 for mixture of 0 % local sand and gravel + 100% aggregate from Barabai.
The Marshall Stability values obtained are 800 kg, 960 kg, 1010 kg, 1150 kg, 1500 kg and 2100 kg for Variation 1 to 6, respectively, and they are for optimum asphalt of 5.45 % , 5.15 % , 4.93 % , 5.10 %, 5.23% and 5.30 %, respectively. The production cost per m3 asphaltic mixture arc Rp 1,138,546.00., Rp 1,351,996.00., Rp 1,124,813.00, Rp 1,196,890.00., Rp 1,242,159.00. and Rp 1,337,162.00, for Variation 1 to 6, respectively.
Marshall immersion tests for Variation 4, 5 and 6 produce Retained Stability Index of 77.3%, 87.1%, 77.45%, respectively, which mean the retained strength are exeeding the minimum acceptance of 75 %.
The mixture of Variation 4 is selected to be used in Barito Selatan district because its optimum usage of local aggregate and 11.47% saving cost when compared with Variation 2 that involves only imported aggregate from Barabai. It is also found that the Variation 6 is the best in quality for heavy traffic, yet it is still cheaper than the Variation 2.

Asphalt Mixing Plant Is...

2009-10-21T04:35:00.000-07:00

What is Asphalt Mixing Plant?
Asphalt Mixing Plants are equipment which is generally used by various manufacturing companies for construction of strong and good quality roads on larger scale. In this equipment various composite material, fillers (stone dust), sand and binder are combined together in right proportion under favorable temperature pressure so enough that aggregate material can developed into hard and standard form. This process is very important for the basic development of good quality roads that is why it is very essential to use equipments like Asphalt Mixing Plant so as to give strong from of aggregate and macadam.

Roads are considered as arteries of nation because it is only roads which connect one place to another place of entire nation. Roads construction takes lot of time so this is necessary to design roads strongly and effectively because once roads would not be constructed properly then it is very hard for any one to construct it regularly. Various equipments and materials unites together to form strong and powerful roads. Asphalt Mixing Plant is also one of them which plays vital role in providing good featured roads. It helps in assimilation of different composite material for making basis of road construction powerful and effective.

Point of consideration before going for Asphalt Mixing Plant
Various manufacturing companies are providing you their different classes and categories of Asphalt Mixing Plant such as Asphalt Drum Mix Plant, Asphalt Batch Mix Plant, Asphalt Mobile Mix Plant and many other more forms. But when you are going for any categories you required taking certain points into consideration before purchasing made. Some points of considerations are described below: -

* Look properly about different specification of Asphalt Mixing Plant like its 4 Bin Feeder, slinger conveyor, control cabin, load out conveyor, bitumen tanks, dryer drum, multi cyclone exhaust, vibrating screen and the system installed in control cabin. After satisfying with complete specification and feature of Asphalt Mixing Plant according to your need and requirement then you can make your purchase.
* After satisfying all features and specification of Asphalt Mixing Plant it is necessary for you to notice closely about all parts of asphalt mixing plant whether good quality components are used or not and they must contain ISI certification mark.
* Your purchasing Asphalt Mixing Plant must satisfy you with your desire need and requirement.

Construction And Quality

2009-10-21T04:21:00.000-07:00

Role of Asphalt Mixing Plant in Construction of strong and quality Infrastructure
The importance and significant role of Asphalt Mixing Plant in construction of strong and good quality Infrastructure can't be ignored. This equipment is always used the places where construction process going on larger basis mainly used in road and larger buildings construction.

Asphalt mixing plant is equipment in which aggregate of composite material, macadam, and stone dust are combined together in right proportion under accurate temperature so that they can get strong and constant shape and size. Realizing its great importance and value in construction of good quality Infrastructure its demand increased rapidly which leads to increase in its supply. That is why various asphalt manufacturing company introduced their different categories of Asphalt Mixing Plant in the market so that customers can get benefits as much as possible. Presently you can get different categories of it such as Asphalt Drum Mix Plant, Asphalt Batch Mix Plant, Mobile Hot Mix Plant, and Mobile Concrete Plant in the market.

But before going for any categories of Asphalt Mixing Plant it is better for you to take close notice about the quality of parts and equipment which are implemented in it. They must contain ISI like certification marks. Also compare about the processing and loading ability of asphalt mixing plant which you are going to purchase. It must suitable for your needs and requirement of work.
After satisfying with the quality and superiority of parts, you can make purchase of Asphalt Mixing Plant. It is very essential for you because you must get complete value and satisfaction for the amount which you are investing against your desire requirement of Asphalt Mixing Plant

How To Use And Operate ( Operational Guide 11 )

2009-07-30T03:32:00.000-07:00

Use and Operation:
5.1 The preparative work before starting up:
Before producing, should ask the technician to check the machine, add the lubricating oil, clear up the sundries, etc., and make the preparation work.
1. Check all equipments and solve the problems in time if have.
2. Prepare the feeder and the transportation vehicles well.
3. All the staff should be at their own position.
4. Check the pre-storing of various raw materials (aggregates, filler, bitumen, etc.) that the production needs, should purchase if being insufficient.
5.2 Operation and regulation of starting the machine:
The order of starting:
Turn on the bitumen circulation pump at first →→→Air-introduced machine of dust remover →→→Air compressor →→→Shut off the discharging gate of mixer →→→Mixer →→→Closed round vibration sifter →→→Hot aggregate elevator →→→Filler elevator →→→Dry roller →→→Coal burning system (not add the coal) →→→Water-spray system of dust remover →→→Gradient belt feeder →→→Small vibration sifter →→→Aggregate feeder →→→Ignition and heating (coal powder) →→→After the flame is stable →→→Put into the aggregates to produce normally.
Attention:
1. During the course of starting, there should be the intervals of 15-20 seconds between every start in order to reduce the waving of voltage.
2. While using the sack cleaner, should add the aggregates first, then light a fire until the aggregates enter into the inlet of the hot aggregate elevator, then goes on heating. Now pay more attention to preventing the flame temperature from being too high, it is apt to cause the damage of the sack.

5.3 Operation regulating and attentions of the continuous production:
1. For the aggregates in the hopper of feeder, should be a full state and add in time, shouldn’t be less than half a hopper at least, otherwise will appear the uneven phenomenon. The ore powder also should be added in time for preventing the ore powder from being condensed, try hard to avoid the ore powder staying in the temporary storage too long.
2. According to the feeding state of the spewing mouth, adjust the matched proportion of the aggregate feeder so that reach the needed proportion. Namely, should drop down the rotating speed of motor according to the specification of the spewing materials.
3. The operation, regulation and attentions of the burning system:
Start unloaded every parts first before putting into production, shut off the damper of burner, then open the fire-introduced valve to light a fire. At the moment, shouldn’t open the air-blower, the damper of air-introduced machine should be the smallest, open the valve of oil nozzle to fire. Here, the coal is fired in the burning room, preheat the dry roller, shut off the valve of the fire-introduced device after the flame is stable, and stop to supplying the diesel oil for avoiding the ignition’s insufficiency, then start the other unit, begin to add the cold aggregate. When the aggregates in the hot aggregated storage reach a certain quantity, begin to scale the aggregates and go on mixing to producing.
Attentions: For the fuel ignition device, oil amount should be small while lighting a fire, and the damper should be smaller than the damper when it works normally; If one-time ignition fails, should shut off the loop rapidly, and open the damper to blow the storing oil in the hearth and then can go on firing again, especially for the hot stove, because the uninflammable oil fog enter into the hearth (or dry cylinder), it will boil off if meeting the heat, it is very much easy to make the stove burst. So after firing successfully, adjust to the needed oil amount and the wind pressure, when the coal are fired in burning room, the flame is stable, shut off the total valve of the ignition device to stop supplying for the diesel oil, here the coal burner can work normally and can add the cold aggregates.
4. Pay attention to adding the bitumen regularly, and guarantee the bitumen temperature in the tank and the feeding temperature should be between 120 -150℃ (or confirm according to the needs).
5.Check the operating situation at any time, advert the temperature and the wave of current in the meter, unusual strike, noise, whether the lubricating oil is sufficient; Whether the belt and chain run steadily; For the belt and chain, it isn’t permit to deviate from the drive groove, especially the belt of the air compressor.
6. While running, only the operator can enter the monitoring room (operation room). The repairman, keeper should put on the safe helmet when enter into the construction field, shouldn’t wear the loose-bodied clothes, pay attention to the security at any time for guaranteeing the safe operation. Especially, shouldn’t be closed to the running parts, swing parts, drive belt, vibration part, spring position, etc., as well as the idler, bitumen pipeline so as not to cause the brush-burn, scald etc..
7. Pay attention to observing the distance between the vehicles and equipments; forbid taking place the impact accidents.
8. After launder the bitumen pipelines with the diesel oil, should let out the residual diesel oil in the bitumen measuring hopper in time, otherwise it is apt to explode after mixing with the hot bitumen.
5.4 Operation of normal parking and attentions:
The principle of normal parking: Should clear up the storing materials (except for the aggregate feeder, hot aggregate storage) when using up the bitumen in the bitumen measuring tank, and prevent the filler from storing for a long time, can encapsulate separately to prevent the ore powder from being made moist, congeal, consequently influence the transportation.
Should " Clear up " before shutting down, namely use the aggregates of several kinds of specifications reserved, had better no less than three kinds of specifications, the weight is no less than 0.5 tons. In the beginning, use the aggregates of the big specification, then use the aggregate of the small specification, finally use the sand, just like this, can clear up the remaining bitumen in the mixer, the aggregates passed cleaning can still continue to be use, so should send into the corresponding storehouses according to their specifications.
The order of normal parking:
Shut off the bitumen circulation pump first, then overturn for 5 minutes (draw back the bitumen in the pipeline to the bitumen tank) →→→Aggregate feeder →→→ Gradient belt feeder →→→Hot aggregate elevator (Carry out the aggregates in dry roller) →→→Closed round vibration sifter →→→Mixer →→→Burner →→→Ten minutes later, stop dust remover to spray the water →→→Air compressor →→→15 minutes later, stop the air-introduced machine →→→Dry roller →→→(shut down for a long time), let out the remaining bitumen in the measuring tank (The unmarked time interval is about 20-25 seconds).
Open the discharging gate of the mixer, don’t be in the position of shutting off, it is difficult to restart the mixer because of the residual condensed bitumen. So please shut off the discharging gate before the mixer restarts again.
It isn’t need to clear up or maintain when the machine put into production after normal parking 1 hour later, but should discharge the remaining bitumen in the tank so as not to condense

Groundwork And Instalation ( Operatioanl Guide 10 )

2009-07-30T03:30:00.000-07:00

Groundwork construction and installation debugging
4.1 Construction of groundwork
Before installing, the user can select and layout the place according to the plane chart that our company offered (or inform our technician and erector go to the building site for guiding), line according to the layout size, make the groundwork well and per-remain the bolt holes; It is permit to install the equipments after the groundwork congealed.
User should have whole, reasonable planning to the place, the position of mixing plant should be convenient for transporting, should reserve the position of the materials field and the bitumen pot. The monitoring room should be in the place that is apt to observe the running situation of the complete machine, the aggregate feeder should be in the place where is easy to feeding.
According to the requests of our company at the same time, the needed place and equipments are as follows:
1. Offer the needed crane, crowbar, rope, etc for unloading temporarily and installing, 25 tons of crane is ok.
2. Offer the temporary storing place that the installation of small parts need, and require a special person to manage.
3. Offer the needed equipments. Just as the welding machine, temporary lighting, power electric junction box, etc.
4. Offer the accommodation for erectors.
5. Arrange 4-6 workers to cooperate with the work of installation and debugging.
6. Make sure 2 operators and 2 technicians to install corporately in advance in order to be familiar with the installation and debugging.
7. Arrange a principal to communicate and consult with our company in time in order to handle with various incidents that are unfavorable to install in time.
4.2 Installation
The installation of the equipment is mainly going on under the instructions of our technician.
4.2.1 The installation of the mixing plant and its parts
First install the width platform, railings and ladder of the hot aggregates storage and mixing layer; put the four braces on the bolts, hang the second layer (the mixing layer) to the braces and fix them well; then fix the anchor bolts, hang the three layer ( the hot aggregate storage layer) to the second layer and fix them well too; finally fix the closed round vibration sifter with the bolts; Now it is time to install the overflow pipe in turn from top to bottom and seal them. Notice to guarantee the upright degree of the mixing plant while installing.
Attentions: In the course of installation, should notice to install the elastic washer to every bolts and screw them tightly; the connections of parts and parts should be adjusted well and seal for preventing the dusts from overflowing.
4.2.2 The installation of hot aggregate elevator:
After fixing the mixing plant well, should install the attachments such as upper platform and railings, etc first, then wind up the upper of elevator with the crane, link with the medium shell and its underside from top to bottom, then take the mixing plant as the reference object to fix the hot aggregate elevator and fix each bolt well. When installing, the outlet of elevator should be connected with the entrance of the closed round vibration sifter directly and seal reliably in order to prevent from overflowing; it should be filled with the asbestos strings between the flange of shell.
4.2.3 The installation of the dry roller and burning system:
For the dry roller, should take the Mixing plant as the reference object to fix its position and burner. While installing, its outlet should be connected with the entrance of the hot aggregate elevator directly and seal reliably in order to prevent from overflowing
The position of burner should be close to the feeding outlet of dry roller, the fire outlet should be connect with the ignition mouth of dry roller directly, besides, should layout the place of the burning materials reasonably, as regards the coal burner, should also confirm the storing place of fuel for preventing being caught in the rain.
4.2.4 The installation of the filler elevator:
First install the attachments such as the upper platform and railings, etc of the elevator, then wind up the upper of elevator with the crane, link with the medium shell and its underside from top to bottom, and then take the mixing plant as the reference object to fix the hot aggregate elevator and fix each bolt well. When installing, the outlet of the hot aggregate elevator should be connected with the entrance of the ore powder interim bin directly and seal reliably in order to prevent from overflowing; it should be filled with the asbestos strings between the flange of shell.
4.2.5 The installation of the cold aggregate feeder system
After fixing the dry roller, can fix the gradient belt feeder, medium filter, aggregate feeder in turn. The connection should be accurate for guaranteeing the feeding passages of the cold aggregate are unblocked and leave a certain distance for throwing materials.
4.2.6. The installation of bitumen feeder system
Emplace the bitumen tank (if users choose the oil-unloading tank and heat preservation tank, should install them in turn); the concrete position is outside the roller. Just like this not only can shorten the length of the connecting pipeline, reduce the thermal losses, but also can make the bitumen easy to mix.
4.2.7 The installation of the water film dust-removing system
First of all, emplace the one-grade single-cylinder cyclone dust catcher. Should fix the underbed first, and then install the single- cylinder cyclone dust catcher.
Second, install the wet type dust-catcher. Should check whether every nozzle link reliably, link with the chimney, water film dust-catcher and the downside water fog dust-catcher in turn, and then connect with the pipe water inlet, at last hang it in the right position.
Third, Place air-introduced machine, connect with the pipelines of dust removing. The connection of the pipelines should be right.
Finally, Install water -supply system, the attachments and pipelines.
4.2.8 The installation of gas flow system:
Attention: While connecting the dust-remover and its pipelines, should fill with the asbestos strings in the flanges for preventing the dust from overflowing or leaking gas.
The installation: Confirm the connection of every component. Should daub the sealant on the joints, and wrap up with the raw material belt in order to ensure its sealed performance.
Attention: Should pay attention to cleaning. Before installing, every pipelines should be blow off, while joining and installing the attachments, should prevent the foreign matters or the dust from entering.
4.2.9 The installation of the monitoring room:
The monitoring room should be in the place where is apt to observe the running of the complete machine, also can observe the situation of vehicles, and can command the vehicles optionally.
4.2.10 The allocation of electric control circuitry:
Can allocate the electric control circuitry by electric engineer after installing all equipments, and dig out the cable trench in the allocation position, and make sure all the joints are reliable.
4.3 Check:
Check whether the installation is correct for every part, whether there is mistake, displacement and omission, whether the localization is firm.
Tips show as follows:
1. The fastening situation of the dry roller, the supported wheel, rolling rings and inner scraper.
2. Whether the bolts on the closed round vibration sifter, the bolts on the motor bracket and the transducer bolts are tightened.
3. Whether the bolts on the mixing arm and the bolts between the vanes are tightened.
4. Sealing performance of dust -remover’s pipeline.
5. Check the sealed situation of air hose, screw gate and every flange joints.
6. Check the fixed situation of the bitumen pipeline joints and flange connection bolts.
7. Check the fastness of the elevator running system, the connection of the medium parts, the fastness of the elevator shell; the elasticity of the elevator chain; if the chain is too loose, can tight it with the underside take-up device.
8. Check the operating parts. Rotate each part by hand, check whether the operation is normal, whether there is any impact, interference, stagnation, lean and other phenomenon, check the elasticity of the chain, belt, etc.
9. Check its lubricated situation; check whether the speeder, bearing, air flow, etc. are adding the oil according to the lubrication table.
10. Check whether the bitumen pipelines are unobstructed, the break-make direction of three-way valve is correct.
11. Check whether the bitumen tank and oil tank are dry, if have any condensed water, should make it clean.
12. Check whether there is the dangerous articles on the device, for instance the bolt, nut, spacer, cotton yarn, iron wire, etc., in order to avoid falling into the drive system and cause the accident and breakdown during the course of production.

4.4 Debugging:
Install all the parts well, connect the power line, go on testing run alone to every part, then carry on unloaded testing run, testing run of feeding so that confirm every system (parts) have no question and trouble and can run normally.
The method as follows:
1.Put through the mixer, closed vibration sifter, hot aggregate elevator, dry roller, the gradient belt feeder, medium filter, aggregate feeder in turn, then go on unloaded testing run and assign the special person to check all the systems, if have some problem should solve in time and then can carry on next step.
2. Check whether the fixed bolts in the mixer, the dry roller and the vibration sifter become loose.
3. Check the swing of the round vibration sifter and its sealed situation.
4. The tightening situation of the elevator’s chain and the rolling chain, the meshing situation of big sprocket and the chain.
5. Whether the dry roller runs steadily, whether there is unusual noise.
6. The tightening situation of the gradient belt feeder, the aggregate feeder’s conveyor belt, and the rotating feeder’s conveyor belt, whether there is the deflective phenomenon, the tightening situation of the bolts, etc.
8. Check the elasticity of air compressor’s belt, the operating, the highest output air pressure, working pressure, pipelines, check whether the air three-element runs normally, the machine runs normally.
9. Run unloaded the dust-catcher system, the asphalt feeder system and the ignition system, at this moment the air-blower, air-introduced machine, fuel pump, bitumen pump are all operating, check the operation situation of every part. Meanwhile, can carry on the test of ignition, burning time can't exceed one minute. Also can testing run the bitumen oil-suction pump and bitumen injection pump, observe whether the bitumen loop and the break-make of valves are correct, whether the bitumen can circulate normally, its operating time can't exceed half a minute.
10. After the unloaded running of every system are normal, and then can fill with the aggregates to test.

Technical Flow ( Operational Guide 9 )

2009-07-30T03:29:00.000-07:00

Technical flow:
The detailed technical flow is as follows:
First of all, Fill various specifications of cold aggregates in the hopper with the loading machine for primary selecting, at the same time sieve out the unused cold aggregates ( bigger than 40mm or self-decided), finally delivery the qualified cold aggregates to the dry roller by the gradient belt feeder.
The aggregates are heated, dried and mixed in roller fully through the burning system; In the course of drying, the dusts and moisture in the cold aggregates are inhaled in the dust catcher, the dusts are separated out from the dust catcher, a few big grain dusts flow into the hot aggregate elevator automatically through one-grade dust catcher and continue to use; Most slight dust are removed by the water dust remover and flow into the sedimentary pool.
The heated hot aggregates in dry roller will flow into the elevator, then will be sent to the closed round vibration sifter on the mixing plant by elevator, the vibration sifter will divided them into five kinds ( four kinds are qualified materials and one is scrap), then enter into the corresponding hot aggregate storage below the sifter separately. Moreover according to the deferent proportion of aggregates, put every kinds of hot aggregates into the measuring hopper in turn, there are three pull transducers on the top of hopper, the transducers will send the weight sign to the switchboard system, and then weigh up in turn in the aggregate measuring hopper controlled by PLC; The computer controls the start order and time of every storehouse gates and air cylinders, as well as the placement of the measuring hopper.
On the other hand, the new ore powder is added into the feeding inlet of the ore powder elevator by manual, they will be sent into the interim storage by the elevator hopper, then throw in the measuring hopper; there are three pull transducers on the top of measuring hopper, the transducers will send the weight sign to the switchboard system, PLC will control the start and close of air butterfly valve for realizing the placement of ore powder.
Meanwhile, the bitumen is heated in the high-temperature bitumen pot, heat it to about 150°C; Three-way spiral valve is in the position of circulation at the same time, the bitumen begin to circulate. Electric air three-way valve not only can make the bitumen circulate but also can send them to the measuring pot; there are also three pull transducers on the top of measuring pot, the transducers will send the weight sign to the switchboard system, PLC will control the weight of bitumen according to the needed bitumen-aggregate ratio.
Finally, put the weighed aggregates, ore powder and bitumen into the mixer to mix. PLC will control the start order and mixing time of every cylinder, it is divided into three control methods of full-automatic, semi-automatic and manual. When it is up to the stipulated time (general 45 seconds), open the discharging gate of mixer, put the even mixture into the carriage and finish the output

Air flow System ( Operation Guide 8 )

2009-07-30T03:22:00.000-07:00

Air flow system

The main composing: An air compressor, a compressed air chamber, the air three-element, the control valve, air rubber tube and air cylinder etc.
Main function: Offer the needed power to every air cylinders and offer the needed compressed air to every devices.
The compressed air that the air compressor produces, pass the disposal of the water separator and oil sprayer (air three-element), make the air device get the pure and dry high-pressure gas. The electromagnetic valves control the moving of every air cylinder to finish the opening and closing of every material gate (or three-way valve).
Attentions:
1. Adjust the output pressure of air compressor to max. 0.8MPa during running.
2. The whole air flow system does not allow having phenomenon of leaking gas.
3. Compressed air bag and three-element water separator should drain one time per man shift.
4. Air three-element oil sprayer should be about 10 drips per minute when running and the oil sprayer can't lack the oil in oil sprayer.
5. Air compressor should be put on the clean place of the mixing plant and forbid contacting the dust.

The structural sketch shows as follows:

11 Dust catcher system
Dust catcher system is consisted of the single-cylinder cyclone dust catcher, combine wet type dust catcher, deposition-pool, submersible pump and attachments, air-introduced pipeline, air-introduced machine, etc. (also can select the sack dust catcher according to the needs)
One grade dust-removing (Dry Cyclone) adopts the single-cylinder cyclone dust catcher, can remove the big grain dusts and send them into the hot aggregate elevator for using directly.
Second grade dust-removing adopts the water-fog dust catcher, can remove the small grain dusts and lighten the load of water dust remover (Wet Cyclone).
Third grade dust-removing adopts the water film dust catcher, can absorb the slight dust in the water, reduce the discharge density of the dust effectively, and make it meet the requirement of national environmental protection.
Its function mainly has three points:
1, Increase the pressure difference of the both ends of dry roller, improve the passing capacity of the hot current, and improve the heating and dry effect.
2, reduce the density of discharging, make the density of smoke and dust discharged accord with the national requirements for environment protection.
3, the wind pipes are connected to the vibration sifter, can remove the dust in the vibration sifter effectively, and offer the negative pressure for the aggregate’s delivery, can reduce the leakage phenomena on every sealed position.
The structural sketch is as follows

12 Electric control system
The electric control system is mainly consisted of the container controlling room (selective), high voltage switch board, and low voltage switch board, control cabinet cupboard, etc.
The main functions: Offer the power supply for the equipments; carry on the monitoring for the productive steps. Can realize the automatic, semi-automatic and manual control.

Vibrating Sistem ( Operational Guide Asphalt Plant 7 )

2009-07-30T03:10:00.000-07:00

2.8 Closed round vibration sifter
Closed round vibration sifter is consisted of the sifter, bracket, spring, screen net, sealed cover, vibration axle, motor, belt, etc.
Main function: Put the different specifications of aggregates that passed the heating, screen the aggregates according to the size of grain in order to go on the accurate measurement and match before mixing.
This kind of vibration sifter adopts the structure of the eccentric axle, a 11kw motor drive, the sifter net is three and a half layers, the size of the mesh is 5~37mm, the vibration frequency is about 890 times /m, the swing is 6-8mm, the disturbing force can be adjusted through regulating the superposition of the eccentric block. In addition, it is also equipped with the amplitude indicator on the sides of device; the amplitude should be about 5-7 mm when it operates normally.
The structural sketch of the closed round vibration sifter shows as follows:

Amplitude indicator shows as follows:

The method of observation: The amplitude indicator is shaking with the vibration sifter, we can measure the amplitude according to the optical effect, if appear the black or white cordiform figures will not show the amplitude value, according to the display of the figure: Pattern is for the gray. If do not appear the black or white cordiform figures, you can get the amplitude value from the indicator: The amplitude is 6mm. Or observe the amplitude indicator while operating, the round of 6mm diameter is tangent with its own outer diameter, can also judge the amplitude is 6mm.
The rotating direction of the vibration sifter motor should see the rotating sign. While rotating to the low end from the upside of the belt, the sieving output is high, but the efficiency is low; on the contrary, the sieving output is low, but the efficiency is high, you can choose according to the debugging situation.
Notes: The amplitude should not be too high so as not to wear and tear the bearings; should add the lubricating oil in time at the same time, recommend adding one time every four hours

Mixing Plant ( Operational guide 6 )

2009-07-27T21:29:00.000-07:00

Main Mixing plant

This system mainly includes: Hot aggregates storehouse total, mixing layer total.
2.7.1 Hot aggregate storage total
Hot aggregate storage is consisted of the bin, gate, air cylinder, overflow pipe, level meter, thermometer, etc. it is mainly using for store the sifted hot aggregates, in addition, there is an air cylinder controlled by the electromagnetism valve on the bottom of each storehouse to offer the quantitative aggregates. Moreover every room of the material storehouse is equipped with the level meter, which can adjust the feeding speed of the feeder. When the storehouse is full, it can overflow the surplus aggregates through each outlet of the hot aggregate storage, and delivery them to the mixing plant; now there is the pressure –relief pipeline in the hot aggregates storage, it can make the inner pressure release through the pipeline and avoid the dust to flying out. Finally there are four overhauling stations on the one side of the hot aggregate storehouse, and matched with the ladder, easy to overhaul and maintain.
Ore powder storage is mainly consisted of the pneumatic butterfly valve and ore powder storing hopper, etc. it is mainly used for weighting up the ore powder in the hopper, put the quantitative filler into the mixer, and then mix them with the hot aggregates and bitumen.
2.7.2 Mixing layer total
This device includes: The principal part of mixing layer, hot aggregate measuring device, filler measuring device, bitumen measuring device, working layer legs and ladder etc.
(1) The measuring device of the stone hot aggregate:
The measuring device of the stone hot aggregate is mainly consisted of the measurer, the pull transducer, air cylinder and emptying door etc. Weigh up the weight through 3 pull transducers, the signal pass the computer, the real aggregate weight reveals on the display screen, the precision: ± 0.5%;
(2), Filler measuring device:
Filler measuring device is mainly consisted of the measurer, the pull transducer, air cylinder and emptying door etc. Weigh up the weight through 3 pull transducers, the signal pass the computer, the real aggregate weight reveals on the display screen, the precision: ± 0.5%;
(3), Bitumen measuring device
It is mainly consisted of the measurer, the pull transducer, air cylinder and bitumen emptying valve etc. Weigh up the weight through 3 pull transducers, the signal pass the computer, the real aggregate weight reveals on the display screen, the precision: ± 0.25%;

Attentions of Installation and debugging:
Notice to make every gates rotate flexibly, it should be accurate to find out the questions and reasons, it should be rational to deal with the problem.
The structural sketch of the mixing plant shows as follows:

Mixer:
The structure composing: It is mainly consisted of the cycloid speed-down motor, chain wheel, chain, synchronous gear, mixing axle, mixing bearing pedestal, mixing arm, mixing vane, shell, upper cover, wear-resisting board, etc. The mixer is the key part of the bitumen mixture mixing equipment. The structural sketch shows as follows:.

Main function: According to a certain matching ratio, mix round the weighed aggregates, filler and bitumen, then mix into the finished materials needed evenly.
The mixer belongs to the horizontal double-axle spiral mixing mode, the vanes, mixing arm and board are all the chromium molybdenum alloy, the mixing arm is the cast steel material, which has very strong anti corrosive and wear-resisting performance, can lengthen its service life greatly. 30kW speed- down motor can mix the aggregates, filler and bitumen fully through the function of chain wheel, chain, synchronous gear, mixing axle and vanes, and then make the finished material

Bitumen Feeder System ( Operational Guide Asphalt Plant 5 )

2009-07-27T20:40:00.000-07:00

2.5 Bitumen feeder system
The main composing: Bitumen manifold, high viscous heat-preservation bitumen pump, 3-way valve, the bitumen measuring hopper, bitumen nozzle, heat-preservation sleeve, etc.
Main functions: Offer and delivery the quantitative bitumen.
The structural sketch of the bitumen feeder system shows as follows:
2.6 Bitumen storing system
Bitumen Storing system belongs to the self-selected parts, the user can purchase freely according to whether own the bitumen storage, the purchase cycle, whether need to heat the bitumen, etc. We generally recommend choosing 30t high-temperature bitumen tank + 50t heat-preservation bitumen tank (must also purchase the heating device)

Hot And Filler Elevator ( Operational Guide Asphalt Plant 4 )

2009-07-27T20:13:00.000-07:00

2.3 Hot aggregate elevator
The structure composing: Adopt the scoop upright lifting structure, it is consisted of the framework, the conveyor chain, active (passive) wheel, lifting hopper, fastening device and the outer cover, etc.
Main functions: Lift the heated hot aggregates to the vibration sifter on mixing plant for sifting.
Its rated feeding capacity is 100t/h, the active and passive wheels are all adopting the chain wheel for improving its transmission efficiency; Hopper edge is strengthened board, the inlet and outlet are all the wear-resisting reinforcing steel bars, the lifting hopper is driven through the cycloid speeder, there is installed the clack valve at the ends of the active axe. The upper of the hot aggregate elevator is the overhauling platform; the repairman can maintain and overhaul the machine safely and conveniently at there. There is installed the bearing –slide on the underside passive axle; can tighten the feeding chain with the bar.
The structural sketch of the hot aggregate elevator shows as follows

4 Filler elevator:
Main composing: Framework, feeding chain, active (passive) wheel, lifting hopper, fastening device and outer cover, etc.
Main functions: Lift the filler to the hot aggregates storage on mixing plant for weighing.
Its rated feeding capacity is 20t/h, the active and passive wheels are all adopting the chain wheel to improve the transmission efficiency; Hopper edge is strengthened board, the lifting hopper is driven through the cycloid speeder. The upper of the filler elevator is the overhauling platform; the repairman can maintain and overhaul the machine safely and conveniently at there. It is installed the bearing –slide on the underside passive axle; can tighten the feeding chain with the bar.
The structural sketch of the filler elevator shows as follows:

Dry Roller ( Operarional Guide Of Asphalt Plant 3 )

2009-07-27T19:52:00.000-07:00

2.2.1: Dry roller:
Working mechanism: The dry roller is mainly consisted of the inlet and outlet material box, roller, vane, the rolled rings, the supported idler, the stop idler, the driven device, framework, legs etc. It receives the cold aggregates that the gradient belt feeder delivery, adopts the dry heating method of roller refluent rotation type, delivery the cold aggregates from one end, install the coal (fuel) burner at the other end, then send into the flame and the hot wind, heat the cold aggregate up to the stipulated temperature; There is about 3.5-4 degrees of obliquity in roller, the obliquity can make sure the aggregates are pushed into the feeding outlet. Moreover, there is installed the deferent spiral vanes and the feeding vanes in the roller, so after the aggregates delivered will be heated 3-5 min., they will be scratched into the feeding outlet and then flow into the stone elevator / hot elevator.
Attentions of Installation and debugging:
The debugging of the dry roller is mainly keeping the roller in suspension state; make the catch wheel and the rolling ring in the state of connection and disconnection. Because the idler is the force object, so it is ok that if only guarantee the idler surface inflicts a component force, which can get over the gravity. There out the four idlers should be along with the rolling direction and lean upward at a certain angle, the specified will be decided according to the suspension situation.

2.2: Burning system
For the burner, the user can select the light oil burner or coal burner.

a. Main composing: burner (including the air-blower, oil pump motor), oil pipeline, the bracket of burner etc.
Fuel burner adopts single-slice computer program control, the button or the touch operation, the photoelectric transducer, the temperature storage and other high-tech electric control systems. The only thing you need to do is pressing the “start” key and can start the oil pump, air blower, auto-ignition, the flameout alarm, the auto-control temperature and display, can self-regulate the needed fuel amount according to the temperature of aggregates. In addition, it is matched with the function of manual, when the automatic control system breaks down, can guarantee the normal operation of the burner through the manual system

b. The coal burning device (Optional):
Main composing: Coal-fired hearth, coal pulverizer, fuel ignition system, hearth bracket, coal pipeline etc.
Main function: Offer the needed hot source to the cold aggregates. The advantages: the cost is very low, the maintaining is convenient.
The operating method: Put the diesel tube into the rear of hearth, turn on the diesel pump and add the diesel oil, now ignite the diesel with the manual ignition pole, preheating about 1 minute later, start the coal pulveriser and add the coal, after the flame in being steady (about 3-5 minutes), shut off the diesel oil pump, now just only heat up the cold aggregates in the dry roller with the burning coal.
The characteristics of this four-passage spiral-flow coal burner: The shade is separate: burning stable, difficult to flameout, wide use; Compound spiral-flow: Burning stressed and fully; Air receiver powder: Dregs-proof and protect the bricks; Adjustable flame: Can regulate the length and thickness of the flame and reach the needed flame shape. This kind of burner aims at solving the five big problems of high-efficient, stable burning, low pollution, dregs proof and erosion, and can overcome such the limitations as the unstable burning, the few suitable coal kinds, serious dregs, heavy pollution, easy to be damaged for the brick and so on.
First of all, it can substitute the oil with the coal, can save the fuel expense of mixer, reduce the operating cost greatly.
Second, the special structure and rational layout of the hearth make the coal can burn fully and steadily and without any storing dregs.
Third, for the mutual function of the one-time spiral-flow wind and the adjustable direct-flow wind, not only can burn high-efficiently and stably but also can be suitable for the various coals’ combustion.
Fourth, It is convenient to regulate online: According to the characteristic of various coals and the dry roller, can adjust the length, thickness and strong or weak of the flame at random, the adjustable range is large.
Fifth, Can improve the service life of the brick greatly because of the burning type of air receiver coal;
The requirements of burning:
1) The heat-generating quantity is bigger than 5000 cal / g
2) The volatile component is bigger than 20%
3) The whole moisture is less than 5%
4) The whole Sulphur component is less than 1%
5) Ash content is less than 10%

Operarional guide Asphalt Plant ( 2 )

2009-07-27T19:38:00.000-07:00

2 Gradient belt feeder:
Working mechanism: Gradient belt feeder is kind of belt conveyor and consisted of the framework, roller, high wear-resisting rubber canvas conveyor belt, the upper and lower idlers, active(passive) roller and driven motor, its largest feeding capacity is 100t/h. Its function is to send the qualified aggregates to dry roller continuously and evenly. The active and passive rollers are all matched with the serviceable bearing. At the same time, they are also matched with the fastening device and the right wheel, and can adjust the elasticity and lean of the conveyor belt, in addition, there is installed the cleaning device outside the conveyor belt in order to remove the small aggregates on the conveyor belt. When the rubbers of the cleaning device are worn and torn seriously, should change in time for preventing the device from splitting the conveyor belt.

Attentions of Installation and debugging:
The ring belt is easy to run deflective, it is mainly caused by the unparallel force, this kind of force may be caused by the active (passive) roller’s unparallel, maybe also caused by the horn shape because of the lean of the ring belt joint, can adjust and correct it through tightening the fastening pole and correcting the gradient position of the supporting idler.

2.2 Aggregate heating system
This system mainly includes: Dry roller, burning system.
Main function: Heat the cold aggregates up a certain temperature that the finished mixture needs.

Operational Guide for Asphalt Mixing Plant ( 1 )

2009-07-25T01:10:00.000-07:00

In order to use and maintain Asphalt Plant correctly, guarantee the normal running of this machine, the manual introduce its performance characteristic, structure, installation, operation, maintenance, etc. The operator and maintenance man should be familiar with its performance and structure, use and maintain correctly according to the regulations of operation instruction to guarantee the normal running of every function parts, prevent the unnecessary trouble from taking place, and thus lengthen its service life as much as possible, give play to its best efficiency.
If you find any lacking during usage, please feed the information back to our company or our local office so that we can improve the products quality constantly, and meet your demands better.
This kind of asphalt mixture mixing equipment is consisted of the following eleven systems: Cold aggregate feeder system (include: Aggregate feeder, Gradient belt conveyor, Dry roller, Burning system, Hot aggregate elevator, Vibration sifter system, Filler elevator, Measuring system (include: Hot aggregate measuring device, Filler measuring device, Asphalt measuring device), Mixer, Mixing plant principal part, Electric control system, Gas flow system, Dust removing system, Bitumen feeder system (Elective)

1. Main performance parameter:

1. The rate of production under the standard conditions: 60-80T/h
2, Rated capacity of the mixer: 1000 kg/batch
3, Bitumen aggregate ratio of mixture: 3%-9%
4. The proportion of filler: 4%-12%
5. The outlet temperature for the finished materials: 130°-160°C
6. Measuring accuracy for aggregate: ± 0.5 % (static state measure); ± 2.5 % (dynamic measure)
7. Measuring accuracy for filler: ± 0.5 % (static state measure); ± 2.5% (dynamic measure)
8. Measuring accuracy for bitumen: ± 0.35 % (static state measure); ± 2.0% (dynamic measure)
9. The stability of the feeding temperature for the finished materials ±6 ℃
10. The discharge density of smoke and dust: ≤ 400mg/Nm3 (water dust- removing)
11. The normal average working time: ≥ 100 h
12. The noise of operating: ≤ 70 dB (A)
13, Service life of the machine: ≥ 7000h
14. The total power of installation: About 187kW (excluding the bitumen heating system and the sack cleaner)

2. Main systems’ composition and use
2.1 Cold aggregate feeder system

Structures: Aggregate feeder, Gradient belt conveyor.

Main functions: Passed the primary matching and then send the qualified aggregates to the dry roller.
2.1.1: Aggregate feeder
Working mechanism: This machine belongs to the fixed type module structure, it is made up of four cold materials storehouses, the belt feeder and the aggregate belt conveyor, etc., and the biggest feeding amount is 100t/h. The outside wall of the front two cold storehouses is installed the store-wall vibrator; this cold storage should be filled with the sand and rice stones. For each belt feeder, its output aggregates are all fasten on the below aggregate belt conveyor. The belt feeder and the aggregate belt conveyor are all matched with the fastening device and the right wheel, and can adjust the elasticity of the conveyor belt and its lean, in addition, there is installed the cleaning device outside the conveyor belt in order to remove the small aggregates on the conveyor belt. When the rubbers of the cleaning device are worn and torn seriously, should change in time for preventing the device from splitting the conveyor belt.
Attentions of Installation and debugging:
The ring belt is easy to run deflective, it is mainly caused by the unparallel force, this kind of force may be caused by the active(passive) roller’s unparallel, also maybe caused by the horn shape because of the lean of the ring belt joint, also maybe caused by the moving direction of the ring belt and the feeding mouth length of the hopper are inconsistent; if belongs to the front both, can adjust and correct it with the fastening pole; if belongs to the later, need to loosen the connection bolts of the four suspenders and readjust their position for making its moving direction is consisted with the length of the feeding mouth.

The structural sketch of the aggregate feeder shows as follows:

Technical Drawing Of Asphalt Plant

2009-01-16T01:32:00.000-08:00

Technical Drawing Asphalt Mixing Plant
1. CONTROL ROOM

Available all type of asphalt mixer,
For detail please contact administrator,
2. ASPHALT TANK

Technical Drawing of type as shown.

3. FUEL TANK

Technical drawing
The technical drawing can help the maker or fabricator to make kinds or model of stone crusher for asphalt mixer.
This is only sample of technical drawing of lay out stone crusher
You can contact us to more details about technical drawing in asphalt mixing plant.
We are the professional in making asphalt mixer and Batching Plant.
With Power Coal Direct Burner as the burner of aggregate. Before mixing with asphalt.
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3D Lay out
3D of Lay out Stone Crusher for Asphalt Mixer

Coal direct Burner,Asphalt Mixing Plant,Automatic Control Panel,Bin and Feeder,Asphalt mixer,Batching Plant,Mixed Gas Pruducer
This is vibrating screen to screening aggregate or material appropriate the standard size that wanted.It works by shaking the main body and material dropped.

Next vibrating screen

Automatic Control Panel

2009-01-04T19:02:00.000-08:00

Computer Panel In Asphalt Mixing Plant
So,the automatic system is composed of control panel,super printer,CCTV,color monitor and automatic control for dryer burner.The system is designed to meet automatic and manual operation of plant is short time by input and output of weighing data of materials on keyboard.Operator can overview the actual operation of each major part through the monitor.Asphalt Mixer and asphalt mixing Plant

Bin And Feeder

2008-12-27T19:55:00.000-08:00

The Truncated pyramid bin is for storing aggregates.bin of 4M3 ,5M3,6M3 and more capacity are available depending upon specifications and operating conditions.To feed the aggregate from the cold bin to belt conveyor,one of the following feeder is selectively mounted under the cold bin.Apron feeder ,belt feeder,Recypro feeder,vibrating screen.

Here The visualization of Bin