Seamless elbow

Seamless elbow is a kind of pipe fitting used for pipe turning. It accounts for a large proportion, about 80%, of all the pipe fittings commonly used in the pipe system. Generally, different forming processes are selected for elbows with different materials and wall thicknesses. The forming process of seamless elbow commonly used by manufacturers includes hot pushing, stamping, extrusion, etc

The push forming process of seamless elbow has the characteristics of beautiful appearance, uniform wall thickness and continuous operation, which is suitable for mass production. Therefore, it has become the main forming method of alloy steel and carbon steel elbow, and also used in the forming of certain specifications of stainless steel elbow

Seamless elbow push forming process:. The deformation characteristic of seamless elbow pushing is to determine the diameter of tube blank according to the rule that the volume of metal material remains unchanged before and after plastic deformation. The diameter of tube blank used is smaller than the diameter of elbow. The deformation process of blank is controlled by the core mold, so that the metal flow at the inner arc is compressed, and the other parts thinned due to the expanding are compensated, so that the seamless elbow with uniform wall thickness is deeply embedded

Classification of seamless elbow

Seamless elbow is also called seamless steel pipe elbow. Due to different manufacturing processes, seamless elbow fittings can be divided into hot rolled (extruded) seamless elbow fittings and cold drawn (rolled) seamless elbow fittings. Cold drawn (rolled) tubes are divided into round tubes and special-shaped tubes

The raw material for rolling seamless elbow pipe fittings is round tube blank. The round tube blank will be cut by the cutting machine to process the blank with a length of about one meter, and will be sent to the furnace for heating through the conveyor belt. The billet is sent into the furnace for heating, and the temperature is about 1200 ℃. The fuel is hydrogen or acetylene. Furnace temperature control is a key issue The round tube blank shall be pierced through the pressure piercing machine after being discharged from the furnace. Generally, the more common piercer is the cone roll piercer. This kind of piercer has good production efficiency, good product quality, large piercing and expanding capacity, and can pierce a variety of pipe fittings. After piercing, the round billets are successively cross rolled, continuously rolled or extruded by three rollers. After extrusion, the pipe shall be disconnected for sizing. The sizing machine rotates into the steel embryo at a high speed through a conical drill bit to drill holes and form pipe fittings