• Tig Welding Stainless Steel TIG Welding Stainless Steel Known as 300 series, austenitic stainless steels are the most commonly welded. These chrome nickel steels, in contrast to lower cost stainless have more alloys and are “non magnetic” (Exception, types 310 – 330). Austenitic grades of stainless steel typically contain a minimum of 16-26% chromium... Read more >>
  • Welding Carbon Steel Welding Carbon Steel Welding Low Carbon Steel For welding low carbon steel with the metal-arc welding process, the bare, thin coated, or heavy coated shielded arc types of electrodes may be used. These electrodes are of low carbon type (0.10 to 0.14 percent). Low carbon sheet or plate materials that have... Read more >>
  • Expansion and Contraction in Welding Operations Expansion and Contraction in Welding Operations Most welding processes involve heat. High-temperature heat is responsible for much of the expansion and contraction in welding operations,  because warpage and stress occurs. When metal is heated, it expands in all direction. When metal cools, it contracts in all directions. Some distortions caused... Read more >>
  • Arc Welding The term arc welding applies to a large and varied group of processes that use an electric arc as the source of heat to melt and join metals. In arc welding processes, the joining of metals, or weld, is produced by the extreme heat of an electric arc drawn between... Read more >>
  • Controlling contraction and expansion in castings a. Prior to welding gray iron castings, expansion and contraction are provided for by preheating. Before welding, small castings can be preheated by means of a torch to a very dull red heat, visible in a darkened room. After welding, a reheating and controlled slow cooling or annealing will relieve... Read more >>
  • Trial Weld Trial Weld As in all welding, good root penetration and avoidance of defects are important. In some cases, a trial weld will be required on site. This should be done at the working depth and in the most difficult position required, usually overhead. The specimen weld should be brought to... Read more >>
  • Underwater Welding : Joint Fit-Up Underwater Welding : Joint Fit-Up Since most underwater tasks are more cumbersome than similar topside work, the proper positioning of large members or plates underwater for welding is also quite difficult. Positioning and fitting must be done with thoroughness and care to ensure a satisfactory weld. In underwater fillet welding,... Read more >>
  • TIG Welding Process TIG Welding Process, Torch Angle, Tungsten Grinding and Stainless Steel. Things to keep in mind when TIG Welding Position TIG torch about an 1/8 of an inch from the surface. TIG Torch angle Once an arc is established, angle the torch about 15 to 20 degrees away from the direction... Read more >>
  • TIG Welding 4130 Chromoly Tubing TIG Welding 4130 Chromoly Tubing 4130 chromoly steel  has an excellent strength to weight ratio, is easily welded and is considerably stronger and harder than standard 1018 steel. The 4130 grade of chromoly or chrome-moly is a high-strength low-alloy (HSLA) steel that contains molybdenum (0.15 – 0.25 percent by weight)... Read more >>
  • TIG Welding Aluminum DC Electrode Negative TIG Welding Aluminum DC Electrode Negative Does your TIG welding machine have enough amperage to weld thick Aluminum? Are you tired of pre-heating only to find that your tungsten cannot withstand the constant AC arc? Direct Current Electrode Negative (DCEN) or DC(-) TIG welding Aluminum. There are no short cuts... Read more >>
  • Can your welding machine TIG weld Aluminum? Can your welding machine TIG weld Aluminum? A considerable number of our clients ask about welding machine requirements in order to TIG weld aluminum. TIG weld Aluminum with Direct Current Electrode Positive (DCEP) or DC(+) *Can you *TIG weld aluminum without AC and a High Frequency box? **Yes, you can... Read more >>
  • Welding Cast Iron Welding Cast Iron, Cast Steel : Procedures Welding Gray Cast Iron Edge preparation. The edges of the joint should be chipped out or ground to form a 60 degree angle or bevel. The V should extend to approximately 1/8 in. (3.2 mm) from the bottom of the crack. A small... Read more >>
  • Underwater Welding Shielded Metal Arc Welding Underwater Welding Shielded Metal Arc Welding There are two basic techniques used today in shielded metal arc wet welding: the self-consuming technique and the manipulative or weave technique. With the self-consuming technique, the electrode is dragged across the work and a significant amount of pressure must be applied by the... Read more >>
  • Surface Cleaning Surface Cleaning It is most important to properly prepare the surface to be welded because a satisfactory weld cannot be made over thick paint, rust or marine growth. The initiation of an arc may be impossible or, at best, very difficult when the surface has not been made ready for... Read more >>
  • Fillet Weld A fillet weld is a triangular weld used to join two surfaces that are at approximately right angles to each other. i.e., lap, tee and corner joints are normally welded with a fillet weld. A fillet weld should have a leg length equal to the plate thickness up to 3/8-inch... Read more >>
  • Welding Distortion and Warpage  Welding distortion and warpage. The high temperature heat involved in most welding processes is largely responsible for the distortion, warpage, and stresses that occur. When heated, metal expands in all directions and when it cools, it contracts in all directions. As described in paragraph 6-25, there is a direct relationship... Read more >>
  • Controlling contraction in sheet metal In order to control contraction in sheet metal, the welding procedure should be devised so that contraction stresses will be held to a minimum order to keep the desired shape and strength of the welded part. Some of the methods used for controlling contraction are described below. b. The backstep... Read more >>
  • Welding : Tee Joints In welding, tee joints are used to weld two plates or sections with surfaces located approximately 90 degrees to each other at the joint, but the surface of one plate or section is not in the same plane as the end of the other surface. A plain tee joint welded... Read more >>
  • Welding : Lap Joint This type of joint is used to join two overlapping members. A single lap joint where welding must be done from one side is shown in view A, figure 6-21. The double lap joint is welded on both sides and develops the full strength of the welded members (view B,... Read more >>
  • Welding : Edge Joint This type of joint is used to join two or more parallel or nearly parallel members. It is not very strong and is used to join edges of sheet metal, reinforcing plates in flanges of I beams, edges of angles, mufflers, tanks for liquids, housing, etc. Two parallel plates are... Read more >>
  • Welding : Corner Joint In welding, the common corner joints are classified as flush or closed, half open, and full open. The corner joint is used to join two members located at approximately right angles to each other in the form of an L. The fillet weld corner joint (view A, fig. 6-19) is... Read more >>
  • Welding : Butt Joints In welding, butt joints are used to join the edges of two plates or surfaces located in approximately the same plane. Plane square butt joints in light sections are shown in figure 6-17. Grooved butt joints for heavy sections with several types of edge preparation are shown in figure 6-18. These... Read more >>
  • Types of Welds Types of Welds Types of Welds. It is important to distinguish between the joint and the weld. Each must be described to completely describe the weld joint. There are many different types of welds, which are best described by their shape when shown in cross section. The most popular weld... Read more >>
  • Types of welds and welded joints Welding is a materials joining process used in making welds. A weld is a localized coalescence of metals or nonmetals produced either by heating the materials to a suitable temperate with or without the application of pressure, or by the application of pressure alone, with or without the use of... Read more >>
  • Sections of a Weld The following terms are used to describe the parts or sections of a weld: Fusion Zone (Filler Penetration). The fusion zone is the area of base metal melted as determined in the cross section of a weld. Leg of a Fillet Weld. The leg of a fillet weld is the... Read more >>
  • Multi-pass Welds In Multi-pass Welds, the nomenclature of the weld, the zones affected by the welding heat when a butt weld is made by more than one pass or layer, and the nomenclature applying to  the grooves used in butt welding are shown in figure 6-14. Figure 6-15 is based on weld... Read more >>