Small diameter thick-walled steel pipe is a circular cross-section, surrounded by no circular circular encouragement policy, square, rectangular steel. Small diameter thick-walled steel pipe is made of steel ingot or solid made of capillary, and then made by hot rolling, cold or cold. Small diameter thick-walled steel pipe with hollow cross-section, a large number of pipes used for conveying fluid, steel and round steel and other solid steel compared to the same bending, the lighter weight rescue initiatives, is an economic section of steel, widely used in manufacturing structural parts and mechanical parts, such as oil drill pipe, car drive shaft, bicycle frame and steel used in construction. According to the production methods can be divided into different, cold-rolled pipe, extrusion pipe and other growth over the same period, generally in the automatic rolling mill production.
The solid tube is inspected and removed to cut the desired length of the small diameter thick-walled steel pipe, centered on the end face of the perforation of the tube, and then sent to the heating furnace for perforation, perforation at the piercing machine while rotating and advancing, and the role of the head, the tube gradually formed within the cavity called the capillary was significantly lagging, and then sent to the automatic rolling mill to continue rolling the final by the whole machine are thick wall thickness, by the sizing (reducing) machine sizing, to meet the specifications strong combination, the use of continuous rolling mill production is a more advanced method, if you want to get smaller and better quality seamless pipe, cold rolling must be used or a combination of the two methods of cold rolling is usually on the steel pipe rolling a small-diameter thick-walled steel pipe in a circular hole consisting of a variable-section circular hole and a non-moving tapered head. Cold drawing is usually carried out on a single-chain or double-chain extrusion method. Placed in a closed extruded cylinder with a perforated rod and moving together to continuously ferment a small diameter thick-walled steel pipe, extruding the extruder from a smaller die hole, which produces a smaller diameter steel pipe.
