Zhejiang Max Stainless Steel Co., Ltd. is a modern stainless steel pipe manufacturing enterprise integrating scientific research, production and sales. We have several cold drawing production lines, as well as multiple cold rolling units, CNC lathes and processing centers, mainly producing seamless pipes, bright and annealed pipes, heat exchange pipes, pipe fittings, flanges and other products. Our motto is quality first, Integrity-based, we have established long-term and stable development visions with users from various industries at home and abroad. Our products are produced in strict accordance with: GB, ASTM, DIN, BS, JIS, 3A, EN and other standards. Materials can be provided: austenitic stainless steel, duplex stainless steel, super duplex steel and nickel-based alloy steel and other material products are widely used in high-end fields such as automobiles, petroleum, chemical industry, boilers, electric power, instrumentation, semiconductors, laboratories, etc.
The cold processing process of stainless steel heat exchange tubes includes cold rolling and cold drawing, with the purpose of making them meet higher requirements for cold processed products.
There are 3 methods of cold drawing: ①Plug cold drawing: use the plug cold drawing with the inner diameter of the finished product; ②Mandrel cold drawing: use a mandrel with the same length as the tube for cold drawing; ③Free cold drawing: cold drawing without mandrel .
Among them, the inner wall of the cold-drawn heat exchange tube of the mandrel is smooth, which can achieve a large deformation ratio, and is suitable for cold drawing of long-dimension stainless steel heat exchange tubes.
Let’s talk about the benefits of cold working of stainless steel heat exchange tubes:
(1) It can improve the surface of the heat exchange tube, improve the surface finish, and also improve the corrosion resistance.
(2) Improve the dimensional accuracy. After cold rolling or cold drawing with a mandrel, not only the outer diameter accuracy can be improved, but also the wall thickness accuracy of the heat exchange tube can be improved.
(3) Steel pipes with smaller diameters and thinner walls can be produced.
(4) Cold deformation combined with external treatment can also improve the mechanical properties of the heat exchange tube.
(5) Special size and special section (except round shape) can be made.
The pipe diameter of the cold-drawn steel pipe is carried out by heating or normal temperature to pickle the surface of the end necking, remove the scale, and apply a lubricant.