Seamless elbow forming

A seamless elbow is a type of pipe used for turning a pipe. Among all the pipe fittings used in the pipeline system, the proportion is the largest, about 80%. Generally, different forming processes are selected for elbows of different material wall thicknesses. Currently. Seamless elbow forming processes commonly used in manufacturing plants include hot push, stamping, extrusion, etc.

The raw material of the seamless elbow pipe fitting is a round pipe blank, and the round pipe embryo is cut into a blank having a length of about one meter by a cutting machine, and is sent to the furnace for heating through a conveyor belt. The billet is fed into a furnace and heated to a temperature of approximately 1200 degrees Celsius. The fuel is hydrogen or acetylene. Furnace temperature control is a key issue. After the round billet is released, it is subjected to a through-hole punching machine. The more common perforating machine is a conical roller punching machine. This perforating machine has high production efficiency, good product quality, large diameter of perforation and can wear a variety of pipe fittings. After perforation, the round billet is successively rolled, rolled or extruded by three rolls. After extrusion, the tube should be sizing. The sizing machine is rotated at a high speed by a conical drill bit into a steel core to form a pipe.

Seamless elbow forming method
1. Forging method: The end or part of the pipe is punched by a swaging machine to reduce the outer diameter. The common forging machine has a rotary type, a link type and a roller type.
2. Rolling method: Generally, the mandrel is not used, and it is suitable for the inner edge of the thick-walled tube. The core is placed in the tube, and the outer circumference is pressed by a roller for round edge processing.
3. Stamping method: The pipe end is expanded to the required size and shape with a tapered core on the press.
4. Bending forming method: There are three methods are more commonly used, one method is called stretching method, the other method is called pressing method, the third method is roller method, there are 3-4 rollers, two fixed rollers, one adjusting roller, adjusting With a fixed roll gap, the finished pipe is curved.
5. Inflating method: one is to place rubber in the tube, and the upper part is compressed by a punch to make the tube convexly formed; the other method is to form a hydraulic bulge, fill the middle of the tube with liquid, and the liquid pressure drums the tube into the required Most of the shapes and production of bellows are used in this way.