Of simple ways of joining pipes, the more common are by screwed fittings when there is sufficient wall thickness; by clamping when walls are thin; and by sleeves placed over or inside the pipes, then soldered or brazed, when it is required to make permanent attachments. Screwed fittings are used for conduit and water pipes, the end of each pipe being threaded and screwed into a sleeve A. In the case of water pipes, leakage is prevented by screwing the sleeve to the end of the thread on the pipe, using jointing compound. Serrated jaw grips or pipe wrenches are used for the screwing together and dismantling. Pieces of straight pipe can be joined in this way to make a permanent system. However, if pipes are long, bent, or sections need to be removed without undue disturbance, a running sleeve joint B must be used where required. One piece of pipe is threaded far enough for the sleeve to be run back clear, when, if the pipes are flexible, they can be pulled sideways and one screwed out. The joint on the long thread is made with a lock nut, using a ring or grommet of yarn treated with jointing compound. This is wound round and the lock nut pulled tight.
展开▼
