The processing technology of precision pipe
General precision pipe‘s production technology can be divided into cold drawing and hot rolling.
The production process of cold rolled precision pipe is generally more complicated than that of hot rolled. The pipe billet should be rolled in three rolls at first, and the sizing test should be carried out after extrusion. If the surface does not respond to crack, the round pipe should be cut by cutting machine, and the blank with a length of about one meter should be cut. Then it enters into the annealing process, in which acidic liquid is used for pickling. During pickling, attention should be paid to whether there is a large amount of bubbling on the surface. If there is a large amount of bubbling, it means that the quality of the steel tube cannot reach the response standard.
In appearance, the cold-rolled precision tube is shorter than the hot-rolled precision tube. The wall thickness of the cold-rolled precision tube is generally smaller than that of the hot-rolled precision tube, but the surface looks brighter than the thick-walled precision tube, without too much roughness on the surface and too much burr on the diameter.
Hot rolled precision pipe delivery state is generally hot rolled state after heat treatment for delivery. After quality inspection, the hot rolled precision pipe shall be selected by the staff strictly by hand. After quality inspection, the surface shall be oiled, followed by several cold drawing experiments. After hot-rolled treatment, the perforation experiment shall be carried out. After straightening, the device is transferred to the flaw detection machine for flaw detection experiment, and finally labeled, arranged in specifications, and placed in the warehouse.
Hot rolled precision tubes are divided into general steel tubes, low and medium pressure boiler tubes, high pressure boiler tubes, alloy steel tubes, stainless steel tubes, petroleum cracking tubes, geological steel tubes and other steel tubes. Cold rolled (dial) precision pipe includes carbon thin-wall pipe, alloy thin-wall pipe, alloy thin-wall pipe, stainless steel pipe, stainless steel thin-wall pipe, stainless steel thin-wall pipe and special-shaped steel pipe, in addition to general steel pipe, low-medium-pressure boiler steel pipe, high-pressure boiler steel pipe, alloy steel pipe, petroleum cracking pipe and other steel pipes. The outer diameter of hot-rolled seamless pipe is generally greater than 32mm, the wall thickness is 2.5-200mm, the diameter of cold-rolled precision pipe can be up to 6mm, the wall thickness can be up to 0.25mm, the outer diameter of thin-walled pipe can be up to 5mm, the wall thickness is less than 0.25mm, and the cold rolling dimension precision is higher than hot rolling.