A BASIC GUIDE OF ARC WELDING ELECTRODES

Welding Joints

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Welding joints are formed by welding two or more workpieces, made of metals or plastics, according to a particular geometry. The most common types are butt and lap joints; there are various lesser used welding joints including flange and corner joints.

Butt welds

Butt welds are welds where two pieces of metal are joined at surfaces that are at 90 degree angles to the surface of at least one of the other pieces.^[1] These types of welds require only some preparation and are used with thin sheet metals that can be welded with a single pass ^[2]. Common issues that can weaken a butt weld are the entrapment of slag, excessive porosity, or cracking. For strong welds, the goal is to use the least amount of welding material possible. Butt welds are prevalent in automated welding processes, such as submerged-arc welding, due to their relative ease of preparation.^[3] When metals are welded without human guidance, there is no operator to make adjustments for non-ideal joint preparation. Because of this necessity, butt welds can be utilized for their simplistic design to be fed through automated welding machines efficiently.

Types

Butt joint geometries

There are many types of butt welds, but all fall within one of these categories: single welded butt joints, double welded butt joint, and open or closed butt joints. A single welded butt joint is the name for a joint that has only been welded from one side. A double welded butt joint is created when the weld has been welded from both sides. With double welding, the depths of each weld can vary slightly. A closed weld is a type of joint in which the two pieces that will be joined are touching during the welding process. An open weld is the joint type where the two pieces have a small gap in between them during welding.

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Square butt joints

The square-groove is a butt welding joint with the two pieces being flat and parallel to each other. This joint is simple to prepare, economical to use, and provides satisfactory strength, but is limited by joint thickness. The closed square butt weld is a type of square-groove joint with no spacing in between the pieces. This joint type is common with gas and arc welding.

For thicker joints, the edge of each member of the joint must be prepared to a particular geometry to provide accessibility for welding and to ensure the desired weld soundness and strength. The opening or gap at the root of the joint and the included angle of the groove should be selected to require the least weld metal necessary to give needed access and meet strength requirements.

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Bevel butt joints

Single-bevel butt welds are welds where one piece in the joint is beveled and the other surface is perpendicular to the plane of the surface. These types of joints are used where adequate penetration cannot be achieved with a square-groove and the metals are to be welded in the horizontal position ^[4]. Double-bevel butt welds are common in arc and gas welding processes. In this type both sides of one of the edges in the joint are beveled.

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V-joints

Single-V butt welds are similar to a bevel joint, but instead of only one side having the beveled edge, both sides of the weld joint are beveled. In thick metals, and when welding can be performed from both sides of the work piece, a double-V joint is used. When welding thicker metals, a double-V joint requires less filler material because there are two narrower V-joints compared to a wider single-V joint. Also the double-V joint helps compensate for warping forces. With a single-V joint, stress tends to warp the piece in one direction when the V-joint is filled, but with a double-V-joint, there are welds on both sides of the material, having opposing stresses, straightening the material.

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J-joints

Single-J butt welds are when one piece of the weld is in the shape of a J that easily accepts filler material and the other piece is square. A J-groove is formed either with special cutting machinery or by grinding the joint edge into the form of a J. Although a J-groove is more difficult and costly to prepare than a V-groove, a single J-groove on metal between a half an inch and three quarters of an inch thick provides a stronger weld that requires less filler material. Double-J butt welds have one piece that has a J shape from both directions and the other piece is square.

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U-joints

Single-U butt welds are welds that have both edges of the weld surface shaped like a J, but once they come together, they form a U. Double-U joints have a U formation on both the top and bottom of the prepared joint. U-joints are the most expensive edge to prepare and weld. They are usually used on thick base metals where a V-groove would be at such a extreme angle, that it would cost too much to fill.

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Others

Thin sheet metals are often flanged to produce edge-flange or corner-flange welds. These welds are typically made without the addition of filler metal because the flange melts and provides all the filler needed. Pipes and tubing can be made from rolling and welding together strips, sheets, or plates of material.^[5]

Flare-groove joints are used for welding metals that, because of their shape, form a convenient groove for welding, such as a pipe against a flat surface.

The Tee Butt Weld is formed when two bars or sheets are joined perpendicular to each other in the form of a T shape. This weld is made from the resistance butt welding process.

Selection of the right weld joint depends on the thickness and process used. The square welds are the most economical for pieces thinner than 3/8”, because they don’t require the edge to be prepared.^[6] Double-groove welds are the most economical for thicker pieces because they require less weld material and time. The use of fusion welding is common for closed single-bevel, closed single J, open single J, and closed double J butt joints. The use of gas and arc welding is ideal for double-bevel, closed double-bevel, open double-bevel, single-bevel, and open single-bevel butt welds.

Below are listed ideal joint thicknesses for the various types of butt welding joints. When the thickness of a butt weld is defined it is measured at the thinner part and does not compensate for the weld reinforcement.

Workpiece thickness limits per joint type^{[citation needed]}
Joint type	Thickness
Square joint	Up to ¹⁄₄ in (0.64 cm)
Single-bevel joint	³⁄₁₆–³⁄₈ in (0.48–0.95 cm)
Double-bevel joint	Over ³⁄₈ in (0.95 cm)
Single-V joint	Up to ³⁄₄ in (1.9 cm)
Double-V joint	Over ³⁄₄ in (1.9 cm)
Single-J joint	¹⁄₂–³⁄₄ in (1.3–1.9 cm)
Double-J joint	Over ³⁄₄ in (1.9 cm)
Single-U joint	Up to ³⁄₄ in (1.9 cm)
Double-U joint	Over ³⁄₄ in (1.9 cm)
Flange (edge of corner)	Sheet metals less than 12 gauge^{[clarification needed]}
Flare groove	All thickness

Cruciform

Diagram of a cruciform joint between 3 plates of metal

A cruciform joint is a specific joint in which four spaces are created by the welding of three plates of metal at right angles. In the American Bureau of Shipping Rules for Steel Vessels, cruciform joints may be considered a double barrier if the two substances requiring a double barrier are in opposite corners diagonally. Double barriers are often required to separate oil and seawater,chemicals and potable water, etc.^[7]

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Plate edge preparation

In common welding practices, the welding surface needs to be prepared to ensure the strongest weld possible. Preparation is needed for all forms of welding and all types of joints. Generally, butt welds require very little preparation, but some is still needed for the best results. Plate edges can be prepared for butt joints in various ways, but the five most common techniques are oxyacetylene cutting (oxy-fuel welding and cutting), machining, chipping, grinding, and air carbon-arc cutting or gouging. Each technique has unique advantages to their use.

For steel materials, oxyacetylene cutting is the most common form of preparation. This technique is advantageous because of its speed, low cost, and adaptability. Machining is the most effective for reproducibility and mass production of parts. Preparation of J or U joints is common prepared by machining due to the need for high accuracy. The chipping method is used to prepare parts that were produced by casting. The use of grinding to prepare pieces is reserved for small sections that cannot be prepared by other methods. Air carbon arc welding is common in industries that work with stainless steels, cast iron, or ordinary carbon steel.^[8]

Welding Procedure Specification

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A Welding Procedure Specification (WPS) is a formal document describing weldingprocedures. The purpose of the document is to guide welders to the accepted procedures so that repeatable and trusted welding techniques are used. A WPS is developed for each material alloy and for each welding type used. Specific codes and/or engineering societies are often the driving force behind the development of a company's WPS. A WPS is supported by a Procedure Qualification Record (PQR or WPQR). A PQR is a record of a test weld performed and tested (more rigorously) to ensure that the procedure will produce a good weld. Individual welders are certified with a qualification test documented in a Welder Qualification Test Record (WQTR) that shows they have the understanding and demonstrated ability to work within the specified WPS.

The following are definitions for WPS and PQR found in various codes and standards:

According to the American Welding Society (AWS), a WPS provides in detail the required welding variables for specific application to assure repeatability by properly trained welders. The AWS defines welding PQR as a record of welding variables used to produce an acceptable test weldment and the results of tests conducted on the weldment to qualify a Welding Procedure Specification.

The American Society of Mechanical Engineers (ASME) similarly defines a WPS as a written document that provides direction to the welder or welding operator for making production welds in accordance with Code requirements.^[1] ASME also defines welding PQR as a record of variables recorded during the welding of the test coupon. The record also contains the test results of the tested specimens.

In Europe, the European Committee for Standardization (CEN) has adopted the ISO standards on welding procedure qualification (ISO 15607 to ISO 15614) and on welder qualification (ISO 9606), with the exception of qualification for steel welders, where a new version of the old european EN 287-1 standard still applies. EN ISO 15706 defines a WPS as "A document that has been qualified by one of the methods described in clause 6 and provides the required variables of the welding procedure to ensure repeatability during production welding". The same standard defines a Welding Procedure Qualification Record (WPQR) as "Record comprising all necessary data needed for qualification of a preliminary welding procedure specification". ^[2] In addition to the standard WPS qualification procedure specified in ISO 15614, the ISO 156xx series of standards provides also for alternative WPS approval methods. These include: Tested welding consumables (ISO 15610),Previous welding experience (ISO 15611), Standard welding procedure (ISO 15612) and Preproduction welding test (ISO 15613).

In the oil and gas pipeline sector, the American Petroleum Institute API 1104 standard is used almost exclusively worldwide. API 1104 accepts the definitons of the American Welding Society code AWS A3.0.^[3]

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Gas Welding

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The most common gas welding process is oxyfuel welding, also known as oxyacetylene welding. It is one of the oldest and most versatile welding processes, but in recent years it has become less popular in industrial applications. It is still widely used for welding pipes and tubes, as well as repair work. It is also frequently well-suited, and favored, for fabricating some types of metal-based artwork. Oxyfuel equipment is versatile not only because it is preferred for some sorts of iron or steel welding but also because it lends itself to brazing, braze-welding, metal heating (for bending and forming), the loosening of corroded nuts and bolts, and also is the ubiquitous means for oxy-fuel cutting of ferrous metals.

The equipment is relatively inexpensive and simple, generally employing the combustion ofacetylene in oxygen to produce a welding flame temperature of about 3100 °C. The flame, since it is less concentrated than an electric arc, causes slower weld cooling, which can lead to greater residual stresses and weld distortion, though it eases the welding of high alloy steels. A similar process, generally called oxyfuel cutting, is used to cut metals.^[6] Other gas welding methods, such as air acetylene welding, oxygen hydrogen welding, and pressure gas welding are quite similar, generally differing only in the type of gases used. A water torch is sometimes used for precision welding of small items such as jewelry. Gas welding is also used in plastic welding, though the heated substance is air, and the temperatures are much lower.

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Resistance

Resistance welding involves the generation of heat by passing current through the resistance caused by the contact between two or more metal surfaces. Small pools of molten metal are formed at the weld area as high current (1000–100,000 A) is passed through the metal. In general, resistance welding methods are efficient and cause little pollution, but their applications are somewhat limited and the equipment cost can be high.

Spot welder

Spot welding is a popular resistance welding method used to join overlapping metal sheets of up to 3 mm thick. Two electrodes are simultaneously used to clamp the metal sheets together and to pass current through the sheets. The advantages of the method include efficient energy use, limited workpiece deformation, high production rates, easy automation, and no required filler materials. Weld strength is significantly lower than with other welding methods, making the process suitable for only certain applications. It is used extensively in the automotive industry—ordinary cars can have several thousand spot welds made by industrial robots. A specialized process, called shot welding, can be used to spot weld stainless steel.

Like spot welding, seam welding relies on two electrodes to apply pressure and current to join metal sheets. However, instead of pointed electrodes, wheel-shaped electrodes roll along and often feed the workpiece, making it possible to make long continuous welds. In the past, this process was used in the manufacture of beverage cans, but now its uses are more limited. Other resistance welding methods include flash welding, projection welding, and upset welding.^[25]

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Energy beam

Energy beam welding methods, namely laser beam welding and electron beam welding, are relatively new processes that have become quite popular in high production applications. The two processes are quite similar, differing most notably in their source of power. Laser beam welding employs a highly focused laser beam, while electron beam welding is done in a vacuum and uses an electron beam. Both have a very high energy density, making deep weld penetration possible and minimizing the size of the weld area. Both processes are extremely fast, and are easily automated, making them highly productive. The primary disadvantages are their very high equipment costs (though these are decreasing) and a susceptibility to thermal cracking. Developments in this area include laser-hybrid welding, which uses principles from both laser beam welding and arc welding for even better weld properties, and X-ray welding.^[26]

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Solid-state

Like the first welding process, forge welding, some modern welding methods do not involve the melting of the materials being joined. One of the most popular, ultrasonic welding, is used to connect thin sheets or wires made of metal or thermoplastic by vibrating them at high frequency and under high pressure. The equipment and methods involved are similar to that of resistance welding, but instead of electric current, vibration provides energy input. Welding metals with this process does not involve melting the materials; instead, the weld is formed by introducing mechanical vibrations horizontally under pressure. When welding plastics, the materials should have similar melting temperatures, and the vibrations are introduced vertically. Ultrasonic welding is commonly used for making electrical connections out of aluminum or copper, and it is also a very common polymer welding process.

Another common process, explosion welding, involves the joining of materials by pushing them together under extremely high pressure. The energy from the impact plasticizes the materials, forming a weld, even though only a limited amount of heat is generated. The process is commonly used for welding dissimilar materials, such as the welding of aluminum with steel in ship hulls or compound plates. Other solid-state welding processes include co-extrusion welding, cold welding, diffusion welding, exothermic welding, friction welding (including friction stir welding), high frequency welding, hot pressure welding, induction welding, and roll welding.^[27]

Quality

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Most often, the major metric used for judging the quality of a weld is its strength and the strength of the material around it. Many distinct factors influence this, including the welding method, the amount and concentration of energy input, the base material, the filler material, the flux material, the design of the joint, and the interactions between all these factors. To test the quality of a weld, either destructive ornondestructive testing methods are commonly used to verify that welds are defect-free, have acceptable levels of residual stresses and distortion, and have acceptable heat-affected zone (HAZ) properties. Welding codes and specifications exist to guide welders in proper welding technique and in how to judge the quality of welds.

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Heat-affected zone

The blue area results from oxidation at a corresponding temperature of 600 °F (316 °C). This is an accurate way to identify temperature, but does not represent the HAZ width. The HAZ is the narrow area that immediately surrounds the welded base metal.

The effects of welding on the material surrounding the weld can be detrimental—depending on the materials used and the heat input of the welding process used, the HAZ can be of varying size and strength. The thermal diffusivity of the base material plays a large role—if the diffusivity is high, the material cooling rate is high and the HAZ is relatively small. Conversely, a low diffusivity leads to slower cooling and a larger HAZ. The amount of heat injected by the welding process plays an important role as well, as processes like oxyacetylene welding have an unconcentrated heat input and increase the size of the HAZ. Processes like laser beam welding give a highly concentrated, limited amount of heat, resulting in a small HAZ. Arc welding falls between these two extremes, with the individual processes varying somewhat in heat input.^[31]^[32] To calculate the heat input for arc welding procedures, the following formula can be used:

where Q = heat input (kJ/mm), V = voltage (V), I = current (A), and S = welding speed (mm/min). The efficiency is dependent on the welding process used, with shielded metal arc welding having a value of 0.75, gas metal arc welding and submerged arc welding, 0.9, and gas tungsten arc welding, 0.8.^[33]

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Defects

Main article: Welding defect

There are many types of defects that can occur depending on the material and welding process. Types of defects include cracks, distortion, gas inclusions (porosity), non-metallic inclusions, lack of fusion, incomplete penetration, lamellar tearing, and undercutting.

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Weldability

Main article: Weldability

The quality of a weld is also dependent on the combination of materials used for the base material and the filler material. Not all metals are suitable for welding, and not all filler metals work well with acceptable base materials.

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Unusual conditions

Underwater welding

While many welding applications are done in controlled environments such as factories and repair shops, some welding processes are commonly used in a wide variety of conditions, such as open air, underwater, and vacuums (such as space). In open-air applications, such as construction and outdoors repair, shielded metal arc welding is the most common process. Processes that employ inert gases to protect the weld cannot be readily used in such situations, because unpredictable atmospheric movements can result in a faulty weld. Shielded metal arc welding is also often used in underwater welding in the construction and repair of ships, offshore platforms, and pipelines, but others, such as flux cored arc welding and gas tungsten arc welding, are also common. Welding in space is also possible—it was first attempted in 1969 by Russian cosmonauts, when they performed experiments to test shielded metal arc welding, plasma arc welding, and electron beam welding in a depressurized environment. Further testing of these methods was done in the following decades, and today researchers continue to develop methods for using other welding processes in space, such as laser beam welding, resistance welding, and friction welding. Advances in these areas may be useful for future endeavours similar to the construction of the International Space Station, which could rely on welding for joining in space the parts that were manufactured on Earth.^[34]

Geometry (Welding Joints)

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Welds can be geometrically prepared in many different ways. The five basic types of weld joints are the butt joint, lap joint, corner joint, edge joint, and T-joint (a variant of this last is the cruciform joint). Other variations exist as well—for example, double-V preparation joints are characterized by the two pieces of material each tapering to a single center point at one-half their height. Single-U and double-U preparation joints are also fairly common—instead of having straight edges like the single-V and double-V preparation joints, they are curved, forming the shape of a U. Lap joints are also commonly more than two pieces thick—depending on the process used and the thickness of the material, many pieces can be welded together in a lap joint geometry.^[28]

Often, particular joint designs are used exclusively or almost exclusively by certain welding processes. For example, resistance spot welding, laser beam welding, and electron beam welding are most frequently performed on lap joints. However, some welding methods, like shielded metal arc welding, are extremely versatile and can weld virtually any type of joint. Additionally, some processes can be used to make multipass welds, in which one weld is allowed to cool, and then another weld is performed on top of it. This allows for the welding of thick sections arranged in a single-V preparation joint, for example.^[29]

The cross-section of a welded butt joint, with the darkest gray representing the weld or fusion zone, the medium gray the heat-affected zone, and the lightest gray the base material.

After welding, a number of distinct regions can be identified in the weld area. The weld itself is called the fusion zone—more specifically, it is where the filler metal was laid during the welding process. The properties of the fusion zone depend primarily on the filler metal used, and its compatibility with the base materials. It is surrounded by the heat-affected zone, the area that had its microstructure and properties altered by the weld. These properties depend on the base material's behavior when subjected to heat. The metal in this area is often weaker than both the base material and the fusion zone, and is also where residual stresses are found.^[30]

Laser beam welding

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Laser beam welding (LBW) is a welding technique used to join multiple pieces of metal through the use of a laser. The beam provides a concentrated heat source, allowing for narrow, deep welds and high welding rates. The process is frequently used in high volume applications, such as in the automotive industry.

Operation

Like electron beam welding (EBW), laser beam welding has high power density (on the order of 1 Megawatt/cm²(MW)) resulting in small heat-affected zones and high heating and cooling rates. The spot size of the laser can vary between 0.2 mm and 13 mm, though only smaller sizes are used for welding. The depth of penetration is proportional to the amount of power supplied, but is also dependent on the location of the focal point: penetration is maximized when the focal point is slightly below the surface of the workpiece.

A continuous or pulsed laser beam may be used depending upon the application. Milliseconds long pulses are used to weld thin materials such as razor blades while continuous laser systems are employed for deep welds.

LBW is a versatile process, capable of welding carbon steels, HSLA steels, stainless steel, aluminum, and titanium. Due to high cooling rates, cracking is a concern when welding high-carbon steels. The weld quality is high, similar to that of electron beam welding. The speed of welding is proportional to the amount of power supplied but also depends on the type and thickness of the workpieces. The high power capability of gas lasers make them especially suitable for high volume applications. LBW is particularly dominant in the automotive industry.^[1]^[2]

Some of the advantages of LBW in comparison to EBW are as follows: the laser beam can be transmitted through air rather than requiring a vacuum, the process is easily automated with robotic machinery, x-rays are not generated, and LBW result in higher quality welds.

A derivative of LBW, laser-hybrid welding, combines the laser of LBW with an arc welding method such as gas metal arc welding. This combination allows for greater positioning flexibility, since GMAW supplies molten metal to fill the joint, and due to the use of a laser, increases the welding speed over what is normally possible with GMAW. Weld quality tends to be higher as well, since the potential for undercutting is reduced.^[3]

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Equipment

The two types of lasers commonly used in are solid-state lasers and gas lasers (especially carbon dioxide lasers and Nd:YAG lasers).
The first type uses one of several solid media, including synthetic ruby and chromium in aluminum oxide, neodymium in glass (Nd:glass), and the most common type, crystal composed of yttrium aluminum garnet doped with neodymium (Nd:YAG).
Gas lasers use mixtures of gases like helium, nitrogen, and carbon dioxide (CO2 laser) as a medium.
Regardless of type, however, when the medium is excited, it emits photons and forms the laser beam.

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Solid state laser

Solid-state lasers operate at wavelengths on the order of 1 micrometer, much shorter than gas lasers, and as a result require that operators wear special eyewear or use special screens to prevent retina damage. Nd:YAG lasers can operate in both pulsed and continuous mode, but the other types are limited to pulsed mode. The original and still popular solid-state design is a single crystal shaped as a rod approximately 20 mm in diameter and 200 mm long, and the ends are ground flat. This rod is surrounded by a flash tube containing xenon or krypton. When flashed, a pulse of light lasting about two milliseconds is emitted by the laser. Disk shaped crystals are growing in popularity in the industry, and flashlamps are giving way to diodes due to their high efficiency. Typical power output for ruby lasers is 10–20 W, while the Nd:YAG laser outputs between 0.04–6,000 W. To deliver the laser beam to the weld area, fiber optics are usually employed.

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Gas laser

Gas lasers use high-voltage, low-current power sources to supply the energy needed to excite the gas mixture used as a lasing medium. These lasers can operate in both continuous and pulsed mode, and the wavelength of the laser beam is 10.6 μm. Fiber optic cable absorbs and is destroyed by this wavelength, so a rigid lens and mirror delivery system is used. Power outputs for gas lasers can be much higher than solid-state lasers, reaching 25 kW.^[4]

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Fiber laser

In fiber lasers, the gain medium is the optical fiber itself. They are capable of power up to 50 kW and are increasingly being used for robotic industrial welding.

Plastic Sealing/Welding Technologies

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The purpose of this article is to outline the most commonly used heat sealing technologies in the Industrial Fabrics market using Engineered Textiles with Polymer coatings. Advancements in industrial materials/fabrics, such as greater heat resistance and strength, stronger weaves and coatings, and consistency roll to roll have opened the market up to new applications. These new applications have created a greater demand for sealing technologies that deliver more consistency and speed.

For example, we now have flexible hurricane shields, inflatable aircraft slides, fire resistant clothing, and countless new military products. Applications also exist in the Automotive industry, Photography products, Media storage,and retail promotion.

Common Product examples

Loose leaf binders, Checkbooks, Passport holders, and Shower curtains.

Radio Frequency Welding (RF)

Radio frequency welding is a very mature technology that has been around since the 1940s. Two pieces of material are placed on a table press that applies pressure to both surface areas. Dies are used to direct the welding process. When the press comes together, high frequency waves (usually 27.12 MHz) are passed through the small area between the die and the table where the weld takes place. This high frequency (radio frequency) field causes the molecules in certain materials to move and get hot, and the combination of this heat under pressure causes the weld to take the shape of the die. RF welding is fast. This type of welding is used to connect polymer films used in a variety of industries where a strong consistent leak-proof seal is required. In the Industrial Fabrics Industry, RF is most often used to fuse/weld vinyl (PVC) and polyurethane(PU) coated fabrics. This is a very consistent method of welding.

Please note that Exposure conditions experienced by RF heater operators can cause elevated body temperature, eye irritation, RF burns, and some neurological problems. To reduce exposure conditions the use of Electromagnetic shielding should be used as much as possible without hindering the manufacturing process.

The most common materials used in Radio Frequency Welding are Thermoplastics such as PVC and Polyurethane. It is also possible to weld other polymers such as Nylon, PET, EVA and some ABS Resins.

Hot Air/wedge Welding

Hot air welding uses hot air or a wedge to heat the coating on the fabric where it is to be bonded together. A Nozzle or heated wedge is positioned between two rollers that pull the material through the machine. As the material is pulled through the machine, hot air is applied to the surfaces to be fused together. Pressure from the rollers and heat form the hot air cause the plastic to fuse as the plastic cools. Like Radio Frequency RF—thermal welding is fast.

Ultrasonic Welding

Ultrasonic welding like radio frequency welding creates heat through friction, however,the heat is created between two layers of material rather than within the material itself. It uses a vibrating tool (die) to create the heat. Ultrasonic can be used on almost all plastic material. It is the fastest heat sealing technology available. It is a rather new technology for Industrial Fabric applications, however it can be more costly to weld large surface areas.

Oxy-fuel Welding and Cutting

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Oxy-fuel welding (commonly called oxyacetylene welding, oxy welding, or gas welding in the U.S.) and oxy-fuel cutting are processes that use fuel gases and oxygen to weld and cut metals, respectively. French engineers Edmond Fouche and Charles Picard became the first to develop an oxygen-acetylene welding machine in 1903.^[1]

Oxy-fuel is one of the oldest welding processes, though in recent years it has become less popular in industrial applications. However, it is still widely used for welding pipes and tubes, as well as repair work. It is also frequently well-suited, and favored, for fabricating some types of metal-based artwork. Oxyfuel equipment is versatile, lending itself not only to some sorts of iron or steel welding but also to brazing, braze-welding, metal heating (for bending and forming), and also oxyfuel cutting.

In oxy-fuel welding, a welding torch is used to weld metals. Welding metal results when two pieces are heated to a temperature that produces a shared pool of molten metal. The molten pool is generally supplied with additional metal called filler. Filler material depends upon the metals to be welded.

In oxy-fuel cutting, a cutting torch is used to heat metal to kindling temperature. A stream of oxygen then trained on the metal combines with the metal which then flows out of the cut (kerf) as an oxide slag ^[2].

Torches that do not mix fuel with oxygen (combining, instead, atmospheric air) are not considered oxy-fuel torches and can typically be identified by a single tank (Oxy-fuel welding/cutting generally requires two tanks, fuel and oxygen). Most metals cannot be melted with a single-tank torch. As such, single tank torches are typically used only for soldering and brazing, rather than welding.

Uses

Oxy-gas torches are used for or have been used for:

Welding metal: see below.
Cutting metal: see below.
Also, oxy-hydrogen flames are used:
- In Stone Work for "flaming" where the stone is heated and a top layer crackles and breaks. A steel circular brush is attached to an angle grinder and used to remove the first layer leaving behind a bumpy surface similar to hammered bronze.
- In the glass industry for "fire polishing".
- In jewelry production for "water welding" using a "water torch". [1].
- Formerly, to heat lumps of quicklime to obtain a bright white light called limelight, in theatres or optical ("magic") lanterns.
- Formerly, in platinum works, as platinum is only fusible in the oxy-hydrogen flame and in an electric furnace.

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Apparatus

The apparatus used in gas welding consists basically of an oxygen source and a fuel gas source (usually cylinders), two pressure regulatorsand two flexible hoses (one of each for each cylinder), and a torch. This sort of torch can also be used for soldering and brazing. The cylinders are often carried in a special wheeled trolley.

There have been examples of oxyhydrogen cutting sets with small (scuba-sized) gas cylinders worn on the user's back in a backpack harness, for rescue work and similar.

There are also examples of pressurized liquid fuel cutting torches, usually using gasoline. These are used for their increased portability.

Welding Procedure Specification

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A Welding Procedure Specification (WPS) is a formal document describing welding procedures. According to the American Welding Society (AWS), a WPS provides in detail the required welding variables for specific application to assure repeatability by properly trainedwelders and welding operators.

The American Society For Mechanical Engineers (ASME) similarly defines Welding Procedure Specification (WPS) as a written document that provides direction to the welder or welding operator for making production welds in accordance with Code requirements.

The American Welding Society defines welding Procedure Qualification Record (PQR) as a record of welding variables used to produce an acceptable test weldment and the results of tests conducted on the weldment to qualify a Welding Procedure Specification. The American Society of Mechanical Engineers (ASME), similarly defines welding Procedure Qualification Record (PQR) as a record of variables recorded during the welding of the test coupon. The record also contains the test results of the tested specimens.

Covered Arc-Welding Electrode

2009-09-03T19:57:00.000-07:00

A covered arc welding electrode includes a steel core wire and a flux which is applied to the outside periphery of said steel core wire. The welding electrode can form a superior crack-resisting weld zone even if fluctuating stresses are continually applied to a base metal while the base metal is welded. The flux includes 40 to 60% metal carbonate, 10 to 25% metal fluoride and 4 to 25 metal oxide by weight. The flux comprises 24 to 32% of the total weight of said electrode. The composition of the welding electrode includes 0.005 to 0.05% carbon, 0.1 to 1.1% silicon, 1.5 to 2.5% manganese, not more than 0.007% sulfur and not more than 0.25% nickel by weight and the manganese/sulfur ratio is more than or equal to 350 to 1. In addition, the welding electrode can include 0.01 to 0.10% rare earth metal by weight. In which case, the Mn content may be 1.0 to 2.5% by weight and the manganese/sulfur ratio may be more than or equal to 270 to 1. In addition, the composition of the welding electrode can include titanium and zirconium, the total content of which may be less than or equal to 1.2% the total weight of the electrode, and/or aluminum and magnesium, the total content of which may be less than or equal to 1.2% of the total weight of the electrode.

1. A covered arc welding electrode comprising:
a flux including 40 to 60% metal carbonate, 10 to 25% metal fluoride and 4 to 25% metal oxide by weight; and a steel core wire, onto the outer periphery of which said flux is applied so as to comprise 24 to 32% of the total weight of said electrode, said electrode as a whole being comprised of 0.005 to 0.05% carbon, 0.1 to 1.1% silicon, 1.5 to 2.5% manganese, not more than 0.007% sulfur and not more than 0.25% nickel by weight and in which the manganese/sulfur ratio is more than or equal to 350 to 1.

2. A covered arc-welding electrode as set forth in claim 1, further comprising titanium and zirconium, the total content of which is less than or equal to 1.2% of the total weight of the electrode.

3. A covered arc-welding electrode as set forth in claim 2, further comprising aluminum and magnesium, the total content of which is less than or equal to 1.2% of the total weight of the electrode.

4. A covered arc-welding electrode as set forth in claim 1, further comprising aluminum and magnesium, the total content of which is less than or equal to 1.2% of the total weight of the electrode.

5. A covered arc-welding electrode comprising:
a flux including by weight 40 to 60% metal carbonate, 10 to 25% metal fluoride and 4 to 25% metal oxide; and a steel core wire, onto the outer periphery of which said flux is applied so as to comprise 24 to 32% of the total weight of said electrode;
said electrode as a whole being comprised of 0.005 to 0.05% carbon, 0.1 to 1.1% silicon, 1.0 to 2.5% manganese, not more than 0.007% sulfur, not more than 0.25% nickel and 0.01 to 0.10% rare earth metal by weight and in which the manganese/sulfur ratio is more than or equal to 270 to 1.

6. A covered arc-welding electrode as set forth in claim 5, further comprising titanium and zirconium, the total content of which is less than or equal to 1.2% of the total weight of the electrode.

7. A covered arc-welding electrode as set forth in claim 6, further comprising aluminum and magnesium, the total content of which is less than or equal to 1.2% of the total weight of the electrode.

8. A covered arc-welding electrode as set forth in claim 5, further comprising aluminum and magnesium, the total content of which is less than or equal to 1.2% of the total weight of the electrode.

Safety Issues

2009-09-03T19:49:00.000-07:00

Welding can be a dangerous and unhealthy practice without the proper precautions; however, with the use of new technology and proper protection the risks of injury or death associated with welding can be greatly reduced.

[edit] Heat and sparks
Because many common welding procedures involve an open electric arc or flame, the risk of burns is significant. To prevent them, welders wear protective clothing in the form of heavy leather gloves and protective long sleeve jackets to avoid exposure to extreme heat, flames, and sparks.

[edit] Eye damage
The brightness of the weld area leads to a condition called arc eye in which ultraviolet light causes inflammation of the cornea and can burn the retinas of the eyes. Goggles and helmets with dark face plates are worn to prevent this exposure and, in recent years, new helmet models have been produced featuring a face plate that self-darkens upon exposure to high amounts of UV light. To protect bystanders, transparent welding curtains often surround the welding area. These curtains, made of a polyvinyl chloride plastic film, shield nearby workers from exposure to the UV light from the electric arc, but should not be used to replace the filter glass used in helmets.[26]
Those dark face plates must be much darker than those in sunglasses or blowtorching goggles. Sunglasses and blowtorching goggles are not adequate for arc welding protection.
In 1970, a Swedish doctor, Åke Sandén, developed a new type of welding goggles that used a multilayer interference filter to block most of the light from the arc. He had observed that most welders could not see well enough, with the mask on, to strike the arc, so they would flip the mask up, then flip it down again once the arc was going: this exposed their naked eyes to the intense light for a while. By coincidence, the spectrum of an electric arc has a notch in it, which coincides with the yellow sodium line. Thus, a welding shop could be lit by sodium vapor lamps or daylight, and the welder could see well to strike the arc. The Swedish government required these masks to be used for arc welding, but they were not used in the United States. They may have disappeared.[27]

[edit] Inhaled matter
Welders are also often exposed to dangerous gases and particulate matter. Processes like flux-cored arc welding and shielded metal arc welding produce smoke containing particles of various types of oxides. The size of the particles in question tends to influence the toxicity of the fumes, with smaller particles presenting a greater danger. Additionally, many processes produce various gases (most commonly carbon dioxide and ozone, but others as well) that can prove dangerous if ventilation is inadequate. Furthermore, the use of compressed gases and flames in many welding processes pose an explosion and fire risk; some common precautions include limiting the amount of oxygen in the air and keeping combustible materials away from the workplace.[28]

[edit] Interference with pacemakers
Certain welding machines which use a high frequency AC current component have been found to affect pacemaker operation when within 2 meters of the power unit and 1 meter of the weld site[29].

Consumable Electrode Methods

2009-09-03T19:46:00.000-07:00

One of the most common types of arc welding is shielded metal arc welding (SMAW), which is also known as manual metal arc welding (MMA) or stick welding. An electric current is used to strike an arc between the base material and a consumable electrode rod or 'stick'. The electrode rod is made of a material that is compatible with the base material being welded and is covered with a flux that protects the weld area from oxidation and contamination by producing CO2 gas during the welding process. The electrode core itself acts as filler material, making a separate filler unnecessary. The process is very versatile, requiring little operator training and inexpensive equipment. However, weld times are rather slow, since the consumable electrodes must be frequently replaced and because slag, the residue from the flux, must be chipped away after welding.[16] Furthermore, the process is generally limited to welding ferrous materials, though specialty electrodes have made possible the welding of cast iron, nickel, aluminium, copper and other metals. The versatility of the method makes it popular in a number of applications including repair work and construction.[17]
Gas metal arc welding (GMAW) is a semi-automatic or automatic welding process that uses a continuous wire feed as an electrode and an inert or semi-inert shielding gas to protect the weld from contamination. When using an inert gas as shield it is known as Metal Inert Gas (MIG) welding. A constant voltage, direct current power source is most commonly used with GMAW, but constant current systems as well as alternating current can be used. GMAW welding speeds are relatively high due to the automatically fed continuous electrode, but is less versatile because it requires more equipment than the simpler SMAW process. Originally developed for welding aluminium and other non-ferrous materials in the 1940s, GMAW was soon applied to steels because it allowed for lower welding time compared to other welding processes. Today, GMAW is commonly used in industries such as the automobile industry, where it is preferred for its versatility and speed. Because it employs a shielding gas, however, it is rarely used outdoors or in areas of air volatility.[18]
A related process, flux-cored arc welding (FCAW), uses similar equipment but uses wire consisting of a steel electrode tube surrounding a powder fill material. This cored wire is more expensive than the standard solid wire and generates extra shielding gas and/or slag, but it permits higher welding speed and greater metal penetration.[19]
Submerged arc welding (SAW) is a high-productivity automatic welding method in which the arc is struck beneath a covering layer of flux. This increases arc quality, since contaminants in the atmosphere are blocked by the flux. The slag that forms on the weld generally comes off by itself and, combined with the use of a continuous wire feed, the weld deposition rate is high. Working conditions are much improved over other arc welding processes since the flux hides the arc and no smoke is produced. The process is commonly used in industry, especially for large products.[20] As the arc is not visible, it requires full automatization. In-position welding is not possible with SAW.

Power Supplies

2009-09-03T19:39:00.000-07:00

To supply the electrical energy necessary for arc welding processes, a number of different power supplies can be used. The most common classification is constant current power supplies and constant voltage power supplies. In arc welding, the voltage is directly related to the length of the arc, and the current is related to the amount of heat input. Constant current power supplies are most often used for manual welding processes such as gas tungsten arc welding and shielded metal arc welding, because they maintain a relatively constant current even as the voltage varies. This is important because in manual welding, it can be difficult to hold the electrode perfectly steady, and as a result, the arc length and thus voltage tend to fluctuate. Constant voltage power supplies hold the voltage constant and vary the current, and as a result, are most often used for automated welding processes such as gas metal arc welding, flux cored arc welding, and submerged arc welding. In these processes, arc length is kept constant, since any fluctuation in the distance between the wire and the base material is quickly rectified by a large change in current. For example, if the wire and the base material get too close, the current will rapidly increase, which in turn causes the heat to increase and the tip of the wire to melt, returning it to its original separation distance.[12]
The direction of current used in arc welding also plays an important role in welding. Consumable electrode processes such as shielded metal arc welding and gas metal arc welding generally use direct current, but the electrode can be charged either positively or negatively. In welding, the positively charged anode will have a greater heat concentration and, as a result, changing the polarity of the electrode has an impact on weld properties. If the electrode is positively charged, it will melt more quickly, increasing weld penetration and welding speed. Alternatively, a negatively charged electrode results in more shallow welds.[13] Non-consumable electrode processes, such as gas tungsten arc welding, can use either type of direct current (DC), as well as alternating current (AC). With direct current however, because the electrode only creates the arc and does not provide filler material, a positively charged electrode causes shallow welds, while a negatively charged electrode makes deeper welds.[14] Alternating current rapidly moves between these two, resulting in medium-penetration welds. One disadvantage of AC, the fact that the arc must be re-ignited after every zero crossing, has been addressed with the invention of special power units that produce a square wave pattern instead of the normal sine wave, eliminating low-voltage time after the zero crossings and minimizing the effects of the problem

STAINLESS STEEL AND SPECIAL ELECTRODES

2009-08-12T21:37:00.000-07:00

1-SATINCROME 308L-17

Description and Applications:

Satincrome 308L-17 is a smooth running, rutile type stainless steel electrode manufactured by CIGWELD for the all positional (except vertical-down) fillet and butt welding of 19Cr/10Ni type stainless steels. The features of Satincrome 308L-17 include high AC arc stability, sound radiographic quality, smooth arc transfer characteristics, very low spatter levels and excellent bead shape and contour. The advanced moisture resistant (MR) flux coating provides improved resistance to start-of-run porosity. Slag lift of Satincrome 308L-17 is enhanced in all welding positions, it is self peeling and non-spitting. Applications of Satincrome 308L-17 include the single and multi-pass welding of 19Cr/10Ni type stainless steel grades including 201, 202, 301, 302,303, 304, 304L, 305, 308 etc.

2-SATINCROME 309Mo-17

Description and Applications:

Satincrome 309Mo-17 is a rutile type, high alloy stainless steel electrode manufactured by CIGWELD for the all positional (except vertical-down) fillet and butt welding of 24Cr/13Ni type stainless steels. The features of Satincrome 309Mo-17 include high AC arc stability, sound radiographic quality, smooth arc transfer characteristics, very low spatter levels and excellent bead shape and contour. The advanced moisture resistant (MR) flux coating provides improved resistance to start-of-run porosity. Slag lift of Satincrome 309Mo-17 is enhanced in all welding positions, it is self peeling and non-spitting. Applications of Satincrome 309Mo-17 include the single and multi-pass welding of matching 309 and 309L stainless steels. Satincrome 309Mo-17 is also suitable for the dissimilar welding of other “300 series” austenitic stainless steels and selected “400 series” ferritic grades to mild or low alloy steels such as 403, 405, 410, 416, 420, 430, 430F-Se, 446 etc and BHP 3CR12.

3-SATINCROME 316L-17

Description and Applications:

Satincrome 316L-17 is a low carbon, rutile type stainless steel electrode manufactured by CIGWELD for the all positional (except vertical-down) fillet and butt welding of 19Cr/10Ni type stainless steels. The features of Satincrome 316L-17 include high AC arc stability, sound radiographic quality, smooth arc transfer characteristics, very low spatter levels and excellent bead shape and contour. The advanced moisture resistant (MR) flux coating provides improved resistance to start-of-run porosity. Slag lift of Satincrome 316L-17 is enhanced in all welding positions, it is self peeling and nonspitting. Applications of Satincrome 316L-17 include the single
and multi-pass welding of matching Molybdenum bearing stainless steels, 316 and 316L. Satincrome 316L-17 is also suitable for the general purpose welding of other “300 series” austenitic stainless steels including 301, 302, 303 and 304/304L, 305, 3CR12 types. The 2.5% Molybdenum content gives increased resistance to pitting corrosion and raises the creep strength for higher temperature applications.

4-SATINCROME 318-17

Description and Applications:

Satincrome 318-17 is a Niobium stabilised, rutile type stainless steel electrode manufactured by
CIGWELD for the all positional (except vertical-down) fillet and butt welding of stabilised and unstabilised 19Cr/10Ni type stainless steels, such as 316, 318 and 321. The features of Satincrome 318-17 include high AC arc stability, sound radiographic quality, smooth arc transfer
characteristics, very low spatter levels and excellent bead shape and contour. The advanced moisture resistant (MR) flux coating provides improved resistance to start-of-run porosity. Slag lift of Satincrome 318-17 is enhanced in all welding positions, it is self peeling and non-spitting. The Molybdenum content of Satincrome 318-17 gives improved resistance to pitting corrosion and the Niobium addition gives improved resistance to intergranular corrosion and good strength retention at elevated temperatures up to ≈ 700°C.

Steel industry

2009-08-07T20:03:00.000-07:00

History of the modern steel industry, Global steel industry trends, Steel production by country, and List of steel producers

It is common today to talk about "the iron and steel industry" as if it were a single entity, but historically they were separate products. The steel industry is often considered to be an indicator of economic progress, because of the critical role played by steel in infrastructural and overall economic development.^[41]

The economic boom in China and India has caused a massive increase in the demand for steel in recent years. Between 2000 and 2005, world steel demand increased by 6%. Since 2000, several Indian ^[42] and Chinese steel firms have risen to prominence like Tata Steel (which bought Corus Group in 2007), Shanghai Baosteel Group Corporation and Shagang Group. ArcelorMittal is however the world's largest steel producer.

The British Geological Survey reports that in 2005, China was the top producer of steel with about one-third world share followed by Japan, Russia, and the USA.^[43]

In 2008, steel started to be traded as a commodity in the London Metal Exchange. At the end of 2008, the steel industry faced a sharp downturn that led to many cut-backs.^[44]

Steel

2009-08-07T19:58:00.000-07:00

Steel is an alloy consisting mostly of iron, with a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most cost-effective alloying material for iron, but various other alloying elements are used such as manganese, chromium, vanadium, and tungsten.^[1] Carbon and other elements act as a hardening agent, preventing dislocations in the iron atom crystal lattice from sliding past one another. Varying the amount of alloying elements and form of their presence in the steel (solute elements, precipitated phase) controls qualities such as the hardness, ductility, and tensile strength of the resulting steel. Steel with increased carbon content can be made harder and stronger than iron, but is also more brittle.

Alloys with a higher carbon content are known as cast iron because of their lower melting point and castability.^[1] Steel is also distinguished from wrought iron, which can contain a small amount of carbon, but it is included in the form of slag inclusions. Two distinguishing factors are its increased rust-resistance and better weldability.

Though steel had been produced by various inefficient methods long before the Renaissance, its use became more common after more efficient production methods were devised in the 17th century. With the invention of the Bessemer process in the mid-19th century, steel became a relatively inexpensive mass-produced material. Further refinements in the process, such as basic oxygen steelmaking, further lowered the cost of production while increasing the quality of the metal. Today, steel is one of the most common materials in the world and is a major component in buildings, infrastructure, tools, ships, automobiles, machines, and appliances. Modern steel is generally identified by various grades of steel defined by various standards organizations.

http://whhz.manufacturer.globalsources.com

2009-07-17T23:48:00.000-07:00

Steel Coil

Product Details


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	Country of Origin: China (mainland) Primary Competitive Advantages: Guarantee/Warranty Price Product Features Prompt Delivery Quality Approvals Main Export Markets: Eastern Europe North America Mid East/Africa Central/South America Asia Western Europe Australasia

Wire Rod-type Steel Coil for Variety Uses

Model Number:Wire Rod

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Key Specifications/Special Features:

Manufacturer: Wu steel, An steel, Sha steel, and more
Materials:
- Carbon construction steel: Q195 and Q215
- Mild carbon steel: SWRM6, SWRM8, SWRM10, SWRM15, SWRM20, GM10Mn, and GM15Mn
- Fine carbon steel: 42A, 42B, 47A, WDT47A, and 47B
- High carbon steel: 62A, 62B, 67A, WDT67A, 67B, 72A, 72B, SWRH82A, WSWRH82B, 82MnA, 80MnA, W77MnA, and SYS72A
- Cold heading steel: SWRCH6A and SWRCH22A
- Welding steel: ER50-3B, WS03, H08A, H08MnA, H08Mn2Si, H08GX, H10Mn2, WER70S-6, WER44-8ò, WQ-1, WQ-2, WQ-3, and WQ-4

Payment Details:

Payment Terms:

Letter of Credit (LC, L/C)

Best Selling Product

2009-07-17T23:46:00.000-07:00

M.S. Welding Electrodes AWS E6013

Model No.:	Welding Electrodes001-1
Location:	China
Minimum Order:	10T
Minimum Order Price:	competitive
Posted Date:	June 08, 2006

Description
Description: Mild Steel Welding Electrodes AWS E6013 is a low-carbon steel electrode with a high titaniume coating and can be used on A.C. or D.C. It has excellent welding technological properties. The arc is stable. The spatter is small. The slag viscosity is moderate. It can be used freely. The slag is easy to clean. The welded seam is smooth and fine and easy to restrike the arc. Application: Suitable for welding sheet metal structure made of low-carbon steel, such as ships, vehicles, building, and general machinery. Specifications: 2.0mm, 2.5mm, 3.0mm, 3.2mm, 4.0mm, 5.0mm Packing: 2.5kg/box or 5kg/box+plastic bag, 20kg/carton, 1000kg/pallet, or as per customers' requirements. Brand Name: GOLDEN MOUNTAIN Price Terms: FOB Qingdao, CIF Payment Terms: ...

Company Profile
Business Type:	Manufacturing
Year of established:	1998
Number of Emplyees:	100+
Website:	http://www.xw-hardware.com

PLANT & MACHINERIES FOR PRODUCING WELDING ELECTRODESWorldwide Welding Supply Directory

2009-07-10T21:32:00.000-07:00

Worldwide Welding Supply Directory

Industrial Classifieds & Auctions - Find Buyers & Suppliers Of Welding Equipment and other Products for Industrial Applications.

Welding Equipment Manufacturers & Suppliers - The Largest & Most Complete Welding Supplies & Equipment Directory on the Web.

IndustrialCOOP.com - Locate Suppliers Of Welding Equipment in North America, Europe & Asia.

Dahching Electric Industrial Co., Ltd. ( http://www.welding-machine-dahching.com ) - Dahching Electric Industrial Co., Ltd. is an experienced resistance welding machine manufacturer. We specialize in producing resistance spot welders, seam welders, projection welders, flash butt welders, three phase welders and capacitor discharge welders.

Wintegral Engineering Pvt. Ltd. ( http://www.wintegral.in) - Laser Welding Equipment For Mould Repair jobshop providing micro-welding precision tooling, moulds and dies as well as plastic manufacturing feedscrew repair and tungsten carbide coatings.

Cinque Solutions Pvt. Ltd. ( http://www.cinquesolutions.com) We specialise in Fire & Heat Protection Clothing, Acetylene-free Gas cutting Systems, Asbestos-free Welding Blankets, Smoke, Heat & Gas Detection Systems, Portable Gas Detectors, Spill Kits & Sorbents, Breathing Apparatus Sets, Breathing Air Compressors, Rescue Tools, Diving Sets and more.

Shanghai Gaoyang Mech. & Elec. Scientific Co., Ltd (www.gyjd2008.com) - Specialized in developing, manufacturing and selling Environmentally friendly and Energy saving Non-pressure oxygen-fuel cutting and welding torch. By inflaming the atomized gasoline and oxygen, the temperature of the flame will reach as high as 3000 so that would shorten the pre-warm time lead, and fasten the cutting speed. Gaoyang cutting torch can be used in many fields, such as cutting, welding and heating carbon steel, stainless steel and iron sheet. Beside this, it also could be used in metallurgy, shipbuilding, and automobile, machine work, as well as farm machinery and repairing.

Haw Shin Product Co., Ltd (http://www.hs-hawshin.com) - Supplier of welding equipment and other industrial equipment such as Super Rite Flowmeter, Water Pumps, Safty Equipments, Pressure regulators, Air Freshener, Petroleum Series, Spray Gun Series, Industry Series, Construction Series and more. With more than 10 years expertises in this field, we always insist on providing the best products and services for our clients, at the most competitive price at the same time.

Danial Industries - Manufacturer of Leather Work/Safety Gloves, Mechanic & Welding Gloves & Other Types

Wenzhou Longwan Foreign Trade Co., Ltd - Manufacturer of Welding Machines, Welding Equipment & Supply

Special Electrodes

2009-07-10T21:19:00.000-07:00

SATINCROME 308L-17

Rutile Type, Stainless Steel Electrode.
Outstanding Operator Appeal!
Now with Improved Slag Lift!
All Positional (except vertical down)
Welding Capabilities.
Advanced Moisture Resistant Flux

Coating.

Classifications:
AS/NZS 1553.3: E308L-17.
AWS/ASME-SFA A5.4: E308L-17.
Description and Applications:
Satincrome 308L-17 is a smooth running, rutile
type stainless steel electrode manufactured by
CIGWELD for the all positional (except
vertical-down) fillet and butt welding of 19Cr/10Ni
type stainless steels.

The features of Satincrome 308L-17 include high
AC arc stability, sound radiographic quality,
smooth arc transfer characteristics, very low
spatter levels and excellent bead shape and
contour. The advanced moisture resistant (MR)
flux coating provides improved resistance to
start-of-run porosity. Slag lift of Satincrome 308L-17
is enhanced in all welding positions, it is self
peeling and non-spitting.

Applications of Satincrome 308L-17 include the
single and multi-pass welding of 19Cr/10Ni type
stainless steel grades including 201, 202, 301, 302,
303, 304, 304L, 305, 308 etc.

Mild Steel Electrode

2009-07-05T20:49:00.000-07:00

This mild steel electrodes, mild steel welding electrodes is a medium coated all position electrode for work of structural importance with medium penetration, soft arc and low spatter, easy to detach slag and can be used in both AC & DC. Typical applications of mild steel electrodes, mild steel welding electrodes is in Structures, Building Construction, Auto bodies, Railway wagons, Vessels, Tanks, Pipelines, Bridges, Ships, Trailers, Building up of shafts, Boilers, Grillls and General fabrication.

What is Welding Electrodes?

2009-05-29T23:39:00.001-07:00

A device that emits, controls or receives electricity. Typically an end point or wire made of metal or some composite material, there are countless electrodes in electrical and electronics products. For example, in a vacuum tube, the cathode emitter is a "negative" electrode. The transparent wires made of indium-tin-oxide (ITO) that cross an LCD screen are electrodes.

ELECTRODE IDENTIFICATION

2009-05-29T23:25:00.000-07:00

Arc welding electrodes are identified using the A.W.S, (American Welding Society) numbering system and are made in sizes from 1/16 to 5/16 . An example would be a welding rod identified as an 1/8" E6011 electrode.

The electrode is 1/8" in diameter

The "E" stands for arc welding electrode.

Next will be either a 4 or 5 digit number stamped on the electrode. The first two numbers of a 4 digit number and the first 3 digits of a 5 digit number indicate the minimum tensile strength (in thousands of pounds per square inch) of the weld that the rod will produce, stress relieved. Examples would be as follows:

E60xx would have a tensile strength of 60,000 psi E110XX would be 110,000 psi

The next to last digit indicates the position the electrode can be used in.

EXX1X is for use in all positions
EXX2X is for use in flat and horizontal positions
EXX3X is for flat welding

The last two digits together, indicate the type of coating on the electrode and the welding current the electrode can be used with. Such as DC straight, (DC -) DC reverse (DC+) or A.C.
I won't describe the type of coatings of the various electrodes, but will give examples of the type current each will work with.

ELECTRODES AND CURRENTS USED

2009-05-29T23:15:00.001-07:00

EXX10 DC+ (DC reverse or DCRP) electrode positive.
EXX11 AC or DC- (DC straight or DCSP) electrode negative.
EXX12 AC or DC-
EXX13 AC, DC- or DC+
EXX14 AC, DC- or DC+
EXX15 DC+
EXX16 AC or DC+
EXX18 AC, DC- or DC+
EXX20 AC ,DC- or DC+
EXX24 AC, DC- or DC+
EXX27 AC, DC- or DC+
EXX28 AC or DC+

CURRENT TYPES

2009-05-29T23:04:00.001-07:00

SMAW is performed using either AC or DC current. Since DC current flows in one direction, DC current can be DC straight, (electrode negative) or DC reversed (electrode positive). With DC reversed,(DC+ OR DCRP) the weld penetration will be deep. DC straight (DC- OR DCSP) the weld will have a faster melt off and deposit rate. The weld will have medium penetration.
Ac current changes it's polarity 120 times a second by it's self and can not be changed as can DC current.

A BASIC GUIDE OF ARC WELDING ELECTRODES

Welding Joints

Butt welds

Types

[edit]Square butt joints

[edit]Bevel butt joints

[edit]V-joints

[edit]J-joints

[edit]U-joints

[edit]Others

Cruciform

[edit]Plate edge preparation

Welding Procedure Specification

[edit]

Gas Welding

[edit]Resistance

[edit]Energy beam

[edit]Solid-state

Quality

[edit]Heat-affected zone

[edit]Defects

[edit]Weldability

[edit]Unusual conditions

Geometry (Welding Joints)

Laser beam welding

Operation

[edit]Equipment

[edit]Solid state laser

[edit]Gas laser

[edit]Fiber laser

Plastic Sealing/Welding Technologies

Common Product examples

Radio Frequency Welding (RF)

Hot Air/wedge Welding

Ultrasonic Welding

Oxy-fuel Welding and Cutting

Uses

[edit]Apparatus

Welding Procedure Specification

Covered Arc-Welding Electrode

Safety Issues

Consumable Electrode Methods

Power Supplies

STAINLESS STEEL AND SPECIAL ELECTRODES

Steel industry

Steel

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Steel Coil

Wire Rod-type Steel Coil for Variety Uses

Best Selling Product

PLANT & MACHINERIES FOR PRODUCING WELDING ELECTRODESWorldwide Welding Supply Directory

Special Electrodes

Mild Steel Electrode

What is Welding Electrodes?

ELECTRODE IDENTIFICATION

ELECTRODES AND CURRENTS USED

CURRENT TYPES

[edit]
Square butt joints

[edit]
Bevel butt joints

[edit]
V-joints

[edit]
J-joints

[edit]
U-joints

[edit]
Others

[edit]
Plate edge preparation

[edit]
Resistance

[edit]
Energy beam

[edit]
Solid-state

[edit]
Heat-affected zone

[edit]
Defects

[edit]
Weldability

[edit]
Unusual conditions

[edit]
Equipment

[edit]
Solid state laser

[edit]
Gas laser

[edit]
Fiber laser

[edit]
Apparatus