Hot Rolled Cold Rolled/Gavanized/Stainless Steel Tube
Seamless steel pipe have hollow cross-sections and are widely used as pipelines for conveying fluids, such as pipelines for conveying oil, natural gas, coal gas, water and certain solid materials. Compared with solid steel materials such as round steel, steel pipes are lighter in weight when the bending and torsional strengths are the same. They are an economical cross-section steel material and are widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipes, automobile transmission shafts, bicycle frames, and steel scaffolding used in construction. Using steel pipes to manufacture annular parts can improve material utilization, simplify manufacturing processes, save materials and processing time, and have been widely used in manufacturing.
The production process of general seamless steel pipe can be divided into cold drawing and hot rolling. The production process of cold-rolled seamless steel pipe is generally more complicated than that of hot rolling. The tube blanks must first be subjected to three-roll continuous rolling, and then to sizing tests after extrusion. If there are no corresponding cracks on the surface, the round tubes must be cut by a cutting machine and cut into billets with a length of about one meter. Then enter the annealing process. Annealing requires pickling with acidic liquid. During pickling, pay attention to whether there are a large number of bubbles on the surface. If there are a large number of bubbles, it means that the quality of the steel pipe does not meet the corresponding standards. In appearance, cold-rolled seamless steel pipe are shorter than hot-rolled seamless steel pipes. The wall thickness of cold-rolled seamless steel pipe is generally smaller than that of hot-rolled seamless steel pipe, but the surface looks brighter than thick-walled seamless steel pipes, the surface is not too rough, and the diameter does not have too many burrs. The delivery state of hot-rolled seamless steel pipes is generally hot-rolled state and delivered after heat treatment. After quality inspection, hot-rolled seamless steel pipe are strictly hand-selected by staff, and then surface oiled, followed by multiple cold-drawing tests. After hot rolling, perforation tests are performed. If the perforation diameter is too large, straightening and correction are performed. After straightening, they are conveyed by the conveyor to the flaw detector for flaw detection, and finally labeled, arranged by specifications, and placed in the warehouse.
Product name |
Seamless steel tube |
Diameter |
General diameter or customized |
Steel Grade |
Q235, Q345, S235JR, S275JR, STK400, STK500, S355JR, GR.B-D |
Standard |
BS1139-1775, EN1039, EN10219, JIS G3444:2004, GB/T3091-2001, BS1387-1985, DIN EN10025, ASTM A53 SCH40/80/STD, BS-EN10255-2004 |
Surface Finish |
Pre-galvanized, hot dipped galvanized, electric galvanized, painted, threaded engraved, socket, polishing, mirror, brushed stainless steel |
Packing |
Packed by steel strips and/or wood case |
Material |
Carbon steel, stainless steel, ally steel |