The hot-pressed elbow is a method of heating the pipe and forming it with professional equipment, then cutting and heating to above the critical temperature, and quickly putting it into the quenching agent after holding it for a period of time, so that its temperature suddenly decreases, and the method of rapid cooling at a faster than the critical cooling rate The elbow is made.
The hot-pressed elbow is used in the place where the pipeline needs to change direction, so it is widely used, mainly used in chemical, civil, construction, industrial production and other fields.
Seamless elbow: The elbow is a kind of pipe fitting used for turning of pipes. Of all the pipe fittings used in the piping system, the largest proportion is about 80%. Generally, different forming processes are selected for elbows with different materials or wall thicknesses. The seamless elbow forming processes commonly used by manufacturers include hot pushing, stamping, and extrusion.
The hot-pressed elbow is a kind of elbow made by the hot-pressing process, which is a kind of pipe fitting. Normalizing can eliminate the network cementite in addition to the eutectoid hot-pressed elbows. For the normalizing of the sub-eutectoid hot-pressed elbows, the lattice can be refined and the overall mechanical properties can be improved. For normalized elbows with less demanding normalizing It is more economical to replace the quenching process.
Stamping forming elbows is the earliest forming process used for mass production of seamless elbows. It has been replaced by hot pushing or other forming processes in the production of commonly used elbows. However, due to the number of production in some specifications of elbows Less, the wall thickness is too thick or too thin.
The product is still in use when it has special requirements. The stamping of the elbow adopts the tube blank equal to the outer diameter of the elbow, and is directly pressed into the mold by the press. Before stamping, the tube blank is placed on the lower mold, the inner core and the end mold are loaded into the tube blank, the upper mold moves downward to start pressing, and the elbow is formed by the restriction of the outer mold and the support of the inner mold. Compared with the hot push process, the appearance quality of stamping is not as good as the former; the outer arc of the stamping elbow is stretched during forming, and there is no excess metal to compensate for it, so the wall thickness at the outer arc is reduced by about 10% . However, due to the characteristics of single-piece production and low cost, the stamping elbow process is mostly used in the manufacture of small batches and thick-walled elbows.
