Butt welding elbow pipe fittings first use CAD skills to design a variety of different diameters, and within 180 degrees, different raw materials butt welding elbow pipe fittings with tube core and core head.  Secondly, the structure of the large pushing machine is reformed to make the production ready to reach the technical requirements of the special large diameter thin-wall high temperature and high pressure special raw material elbow pipe.  Then the special raw material pipe fitting is blanked according to the required size, and hoisted into the large push machine, and the pipe fitting is pushed to produce the large-caliber thin-wall high-temperature and high-pressure special elbow pipe fitting within 180 degrees from various viewpoints.  

 
The pushing method of large diameter elbow pipe fittings is characterized in:    First choose CAD skills designed within 180 degrees butt welding elbow pipe with pipe core and core head, then on the big push machine structure transformation, the production equipment dedicated to push system of large-scale thermal power plants of large diameter thin-walled high temperature, high pressure, special materials of elbow pipe fittings skills requirements, and then the special raw material pipe materials according to the required size, and into a large machine, pipe fittings  Push the production of various points of view within 180 degrees of large-caliber thin-wall high temperature and high pressure resistant special elbow pipe fittings.  
 
 

The raw material of rolling butt welding elbow pipe fitting is round tube blank. Round tube embryo is cut by cutting machine, and the blank with a growth degree of about one meter is processed, and sent to the furnace for heating by conveyor belt.  The billets are fed into a furnace to be heated at about 1,200 degrees Celsius, fueled with hydrogen or acetylene.  The temperature control in furnace is the key problem.  After the round tube billet comes out of the oven, it must go through the pressure punch.  After perforation, the round tube is successively rolled by three rolls, cross - rolled or kneaded.  After kneading, take off the pipe and size.  
 

The sizing machine rotates at high speed through the conical drill bit to drill the steel embryo and form the pipe fittings.  The inner diameter of pipe fitting is determined by the outer diameter length of the drill bit of the sizing machine.  After sizing, the pipe fittings enter the cooling tower and are cooled by water spraying. After cooling, the pipe fittings shall be straightened.  After straightening, pipe fittings are sent by conveyor belt to metal flaw detector (or hydrostatic test) for internal flaw detection.  If there are cracks, bubbles and other problems inside the steel pipe, it will be detected.  Butt welding elbow pipe fittings pipe fittings after quality inspection after strict manual selection.  After quality inspection, paint on the serial number, specification, production batch number, etc.