AWS RWPH pdf free download

AWS RWPH pdf free download.Resistance Welding Pocket Handbook.
Projection Welding In this variation of the resistance welding process, the metals to be welded meet at a local- ized point, which exists to concentrate the force and current. In some parts, such as cross-wire welding, the localized point of contact results from the natural part geometry. Most of the time, the projection must be formed or machined in one of the parts. Figure 3 shows some examples of projections before welding. Additional information may be found in Chapter 2 of the AWS Welding Handbook, 9th Edition, Vol. 3，or Chapter 3 of the RWMA Resistance Welding Manual.
Seam Welding Similar to spot welding, except the circular elec- trodes (seam welding wheels) are rotating when the weld is being made. If the time between the welds is increased such that the welds do not overlap to form a continuous seam weld, the result is known as a roll spot weld. Additional information may be found in Chapter 1 of the AWS Welding Handbook, 9th Edition, Vol. 3, or Chapter 4 of the RWMA Resistance Welding Manual.
Upset Welding (Butt Welding) The ends of the two parts are forced together while welding current and force are applied. Flash Welding During the initial sequence, the parts are held lightly together while current is applied. Then as material is flashed away and the proper temper- ature is reached the parts are forced together to complete the weld. Additional information on these processes may be found in Chapter 3 of the AWS Welding Handbook, 9th Edition, Vol. 3, or Chapter 5 of the RWMA Resistance Welding Manual.
Hot Upsetting In this process, heat is created by electrical current and then the workpiece is upset by the electrode force. Hot upsetting is commonly applied to rivets and pins to lower the force required to create a head and/or bulge. Resistance Brazing/Resistance Soldering These are processes where the heat created by the resistance to current flow through two parts is used to melt a low-temperature filler metal. Resistance Parting ; As the metal is heated by the electric current in this process, force is applied to separate the work- piece midway between the electrodes. Resistance Heating Heat is created in the workpieces for hot forming and heat-treating applications. Additional information on these processes may be found in Chapter 6 of the RWMA Resistance Welding Manual.
Resistance Welding Electrodes The welding electrodes serve three functions: ●They hold the workpieces together under pressure. ●They provide a path for the welding current into and out of the workpieces. ●They cool the outer surface of the workpieces. This permits the inner (faying) surfaces to get hot enough to fuse without welding the workpieces to the electrodes. Electrode Material Types The RWMA has defined classes (groups) of materials with similar properties to make it easier to select the proper electrode material. The important properties to consider for successful resistance welding are the hardness and conductivity of the electrodes. Some of the more common materials are listed in Table 1 (Page 19).
AWS RWPH  pdf download.