Cold drawn precision seamless steel pipes have the characteristics of no oxide layer on the inner and outer walls, high pressure, no disclosure, high precision, high brightness, cold bending, flattening, flattening without deformation, no surface cracks, and anti-rust treatment. Mainly used for the mechanical structure, hydraulic equipment, pneumatic or hydraulic components of automobiles and motorcycles. Detailed process: hot-rolled capillary detection and grinding-capillary pickling-capillary pickling-post pickling-cold drawing-pre-straightening-pickling, lubrication-fine drawing-waste storage and pre-disposal.
In the consumption, demand carefully controls the following points: hair management. The wall thickness of the capillary tube should be uniform, with fewer internal and external surface defects. Equipment for polishing the outer surface and clearing the defects of the inner hole shall be equipped. Review. In the production of cold-drawn precision seamless steel pipes, compared with ordinary cold-drawn steel pipes, hot-rolled capillary pickling and re-inspection processes have been added. This is to ensure that there are no defects such as folds and cracks on the outer surface of the capillary, and to eliminate defects such as folds on the inner surface of the capillary, severe marks, and linen surface.
The surface brightness of the tools used in the production of cold drawn precision seamless steel pipes should generally be higher than Ra0.4, the dimensional accuracy should be higher than H3, and the hardness should be higher than HRC70. At the same time, there will be no sticking of the head or mold during the drawing process. Death phenomenon. The production process of seamless steel pipe manufacturers can be divided into two types: cold-drawn and hot-rolled. The production process of cold-rolled seamless steel pipe is generally more complicated than that of hot-rolled. The tube billet must first stop three-roll continuous rolling, and then stop after extrusion. Trail test.
Assuming that the surface does not respond to cracks, the round tube must be cut by a cutting machine to stop cutting and cut a blank of about one meter in length. annealing. Annealing is a very important link in the production process of cold drawn steel pipes. The quality of annealing not only affects the performance of the steel pipe, but also affects the removal of oxide scale. Therefore, it is necessary to equip a non-oxidizing bright annealing furnace for cold drawn precision steel pipes. Precision seamless steel pipes are made of 10, 20, 30, 35, 45 and other high-quality carbon steels such as 16Mn, 5MnV and other low-alloy structural steels or 40Cr, 30CrMnSi, 45Mn2, 40MnB and other composite steels by hot rolling or cold rolling.