ASTM BS DIN JIS Low Carbon Large Diameter 20-450mm Steel Seamless Pipe

Production of seamless pipe

The process begins with solid steel rounds, or billets, being cut to a specified length and sent through a walking-beam reheat furnace, where temperatures reach nearly 2,300°F. After exiting the reheat furnace, the preheated rounds are turned into a tube shell in the rotary piercing mill as the billets are cross-rolled between two barrel-shaped rolls at a high speed. The seamless shells enter mandrel mill, where they are rolled over a retained mandrel to provide the needed OD size and wall thickness for the next process. The process is carefully monitored using a state-of-the-art hot-wall measuring system. The shells are then reheated for final forming in a 24-stand stretch-reducing mill, where outside diameters are formed to customers' exacting specifications. Wall thickness is again verified using a hot-wall measuring system. After being rotated and advanced on the walking-beam cooling bed, the pipes are batch cut and transferred to an in-process storage area, where they are handled by computer-controlled gantry cranes. 

Electromagnetic Inspection for Large-diameter Seamless Pipe 
Plug mill is equipped with an Amalog-Sonoscope, electromagnetic inspection units after heat treatment. The Amalog-Sonoscope pipe inspection system detects defects by using flux leakage by electromagnetic induction in search coil. Amalog magnetic circuits detect longitudinal defects in both the inside and outside surface. Sonoscope magnetic circuits detect circumferential defects.

Shandong Zhengde Metal Manufacturing Co., Ltd. is a production and sales company integrating hot-rolled steel coils, cold-rolled steel coils, galvanized steel coils, color-coated steel coils, section steel, steel pipes, steel wires, metal mesh, stainless steel, aluminum, copper and other metal products integrated large enterprises. Five production and sales bases have been formed in Binzhou, Liaocheng, Wuxi, Tianjin, Jinan and Tai'an, with more than 100 production lines, 4 nationally recognized laboratories, 2 technical engineering centers, and 5 enterprise technology centers. Products are exported to more than 50 countries and regions such as North America, South America, Europe, Africa, Oceania, Middle East, and Southeast Asia.