Chptr 6 Welding Techniques
6-18. FLAT POSITION WELDING In this position, the welding is performed from the upper side of the joint, and the face of the weld is approximately horizontal. Flat welding is the preferred term; however, the same position is sometimes called downhand. (See view A, figure 6-30 and view A, figure 6-31 for examples of flat position welding for fillet and groove welds). 6-19. HORIZONTAL POSITION WELDING NOTE The axis of a weld is a line through the length of the weld, perpendicular to the cross section at its center of gravity. a. Fillet Weld. In this position, welding is performed on the upper side of an approximately horizontal surface and against an approximately vertical surface. View B, figure 6-31, illustrates a horizontal fillet weld. b. Groove Weld. In this position, the axis of the weld lies in an approximately horizontal plane and the face of the weld lies in an approximately vertical plane. View B, figure 6-30, illustrates a horizontal groove weld. c. Horizontal Fixed Weld. In this pipe welding position, the axis of the pipe is approximately horizontal, and the pipe is not rotated during welding. Pipe welding positions are shown in figure 6-32. d. Horizontal Rolled Weld. In this pipe welding position, welding is performed in the flat position by rotating the pipe. Pipe welding positions are shown in figure 6-32. 6-20. VERTICAL POSITION WELDING a. In this position, the axis of the weld is approximately vertical. Vertical welding positions are shown in view C, figures 6-30 and 6-31. b. In vertical position pipe welding, the axis of the pipe is vertical, and the welding is performed in the horizontal position. The pipe may or may not be rotated. Pipe welding positions are figure shown in figure 6-32. 6-21. OVERHEAD POSITION WELDING In this welding position, the welding is performed from the underside of a joint. Overhead position welds are illustrated in view D, figures 6-30 and 6-31. 6-22. POSITIONS FOR PIPE WELDING Pipe welds are made under many different requirements and in different welding situations. The welding position is dictated by the job. In general, the position is fixed, but in sane cases can be rolled for flat-position work. Positions and procedures for welding pipe are outlined below. a. Horizontal pipe rolled Weld (1) Align the joint and tack weld or hold in position with steel bridge clamps with the pipe mounted on suitable rollers (fig. 6-33). Start file:///C|/Documents%20and%20Settings/Dad/Desktop/welding-theory/ch6.htm (25 of 51)1/8/2006 4:10:51 PM