In the production process of stainless steel seamless pipes, there are differences in the quality of products produced by different production processes. What are the common production processes of stainless steel seamless pipes?
1. Hot rolling: round tube billet-heating-perforation-three-roll cross rolling, continuous rolling or extrusion-stripping-sizing (or reducing)-cooling-straightening-hydraulic test (or flaw detection)- The raw material of mark-in-storage-rolled seamless steel pipe is a round tube blank, which is cut into a 1 meter-long blank by a cutting machine, and the blank is sent to a melting furnace for heating through a conveyor belt. The billet is fed into the furnace and heated at a temperature of approximately 1200 degrees Celsius. The fuel is hydrogen or acetylene. Temperature control in the furnace is a key issue. After the round tube blank is released from the furnace, it must be emptied by a pressure piercer. The ordinary punching machine is a tapered roller punching machine, which has high production efficiency, good product quality, large diameter expansion, and can penetrate various steel types. After piercing, the round tube billet is continuously rolled, rolled or extruded through three rolls. After extruding, remove the pipe and set the diameter. The sizing machine rotates into a billet through a conical drill bit at high speed for punching to form a steel pipe. The inner diameter of the steel pipe is determined by the outer diameter length of the sizing machine bit. After the steel pipe is shaped, it enters the cooling tower and is sprayed with water for cooling. After cooling, the steel pipe is straightened. After straightening, the steel pipe is sent to the metal flaw detector (or hydraulic test) for internal flaw detection by the conveyor belt. If the steel pipe has cracks, bubbles and other problems, they will be detected. After quality inspection, the steel pipes must be selected strictly by hand. After the quality inspection of the steel pipe is qualified, paint the serial number, specifications and production batch number. Crane into the warehouse.
2. Cold drawn (rolled) seamless steel tubes: round tube billet-heating-perforation-upsetting-annealing-pickling-oiling (copper plating)-multi-pass cold drawing (cold rolling)-billet-heat treatment-straightening -Hydraulic test (flaw detection) -Marking-in storage. The rolling method of cold drawn (rolled) seamless steel pipe is more complicated than hot rolled (extruded) seamless steel pipe. The first three steps of their production process are basically the same. The difference is that starting from the fourth step, after the round tube blank is emptied, the round tube blank is started and annealed. After annealing, special acidic liquid should be used for pickling. After pickling, apply oil. Then, multi-pass cold drawing (cold rolling) and special heat treatment of the billet are performed. After heat treatment, it must be straightened. After straightening, the steel pipe is sent to the metal flaw detector (or hydraulic test) for internal flaw detection by the conveyor belt. If the steel pipe has cracks, bubbles and other problems, they will be detected. After quality inspection, the steel pipes must be selected strictly by hand. After the quality inspection of the steel pipe is qualified, paint the serial number, specifications and production batch number. Crane into the warehouse.
In the production process of stainless steel seamless steel pipe, it is very important to choose a suitable production process.
