Next to this thermal condition of alloy elbow shaped outer diameter of the shaped reached the dimensional requirements of the finished wall thickness will be controlled since the material thickness. Bends and pipe wall thickness tolerances are the same, are was ± 12.5%. Because some elbow treated properly, it will distort, which is not allowed. Also, usually the outer diameter of the tip after Tuitou to shaping by plastic molding. plastic mold is actually a presses, to have a mold, two semi-circular, up and down, one each in the alloy elbow to push the system process, under normal circumstances the thickness should not change, but if for reasons tools, some places will happen reduction wall phenomenon, it is generally expected to mention when the wall thickness to add some margin, such as the elbow is the thickness of 8.18mm and 8.5mm tube usually mention about, when to push the system to prevent a partial cut thick and ultra-poor due to integer After a good shape, elbow diameter, wall thickness dimensions are met the requirements. alloy elbow material varied, common carbon steel, manganese, nickel, steel, etc. alloy elbow very versatile ordinary bronze alloy materials in general water pipe elbow is more common, but with the improvement of living standards, many water pipe impact relatively strong pipeline.