When there are two lengths of pipe that must be fitted-up to - gether, they can be aligned by the methods shown in Fig. 14-4A and B. A very effective method is illustrated in Fig. 14-4A, where an ordinary piece of straight angle (or steel angle) is used as a gage to check the alignment. The angle iron must be straight and the burrs on the ends, caused by the saw cuts, must be removed.
The angle iron is first placed on one side of the two pipes, bridging the joint, and then it is placed against the opposite side of
the pipe. In each position an attempt is made to rock the angle iron. When it will not rock in either position, the pipes are aligned. Sometimes, the angle iron is held over the pipes while the tack weld is deposited on the other side.
The second method, shown in Fig. 14-4B, is simply to bridge the joint with a straightedge or with a blade of a rafter square. At least two positions on the pipe, 90 degrees apart, should be checked in this manner. While aligning the pipes in preparation for the first tack weld, the correct root opening must be maintained. This can be done by placing a piece of bent wire between the pipes as shown in Fig. 14-4C. Of course, the diameter of the wire must be equal to the root opening.
The procedure for fitting-up two pipes is illustrated in a step - by-step manner in Fig. 14-5. This general procedure is also used to
the correct root opening.
align the fittings, with appropriate variations, as will be explained further on.