Large diameter thick wall seamless steel pipe is made from steel ingot or solid billet after piercing to be hollow billet then hot rolled to be large diameter thick wall steel pipe or hollow bar. We can also produce the steel pipe to the customized size as clients requirements by heat expanding the pipe. The outer diameter for large size steel pipe is at least 325mm.
Commodity | Thick Wall Large Diameter Carbon Steel Hollow Bar |
Outer Diameter | 325mm-1066.8mm |
Wall Thickness | 25mm-162mm |
Length | 5.8 meters, 6 meters, 9 meters, 11.8 meters |
Grades | Q345B,ST37,ST52,A53 Gr.B,A106 Gr.B, 20# |
Tolerance | Comply with the standard |
Pipe End | Plain end, Beveled end |
Standards | ASTM 53, ASTM A106, GB/T8162, GB/T8163 |
Surface | Black painting, As rolled, Mill finished |
Heat Treatment | Hot rolled, Annealing, Tempered, Hot(Heat) expanding |
Large diameter thick wall seamless steel pipe is made from solid tube ingot or the perforation capillary, then through hot rolling. Large diameter thick wall seamless steel pipe has an important position in the steel industry in our country. According to incomplete statistics, about more than 240 existing seamless pipe production enterprises in China, large diameter thick wall seamless steel tube unit about more than 250 sets of large diameter thick wall seamless steel tube is mainly based on its external diameter of steel pipe, in general diameter 325 mm or more we are called the large diameter steel pipe, thick-walled, general wall thickness in the more than 20 mm, the following is the manufacturing process of steel pipe: steel pipe raw material is steel tube billet, billet through cutting machine cutting the growth degree of about 1 meter of billet, and the conveyor belt to the heating furnace. Billet are fed into the furnace heating, the temperature is about 1200 ℃.Fuel for hydrogen or acetylene. In furnace temperature control is a crucial problem, circular tube billet after go through pressure punch wear empty. General is one of the more common punch is tapered roller puncher, this kind of punch high production efficiency, product quality good, large amount of perforated hole enlargement, can wear a variety of steel grade. After perforation, circular tube billet has been three-roll skew rolling, rolling or extrusion. To take off after extruding tube sizing. Sizing mill by taper drill bits high-speed steel into embryo punching and forming steel pipe. Large diameter thick wall seamless steel pipe diameter by sizing mill bit length to determine the diameter. Large diameter thick wall seamless steel pipe after sizing, into the cooling tower by water spray cooling, steel pipe after cooling, will be straightening.