1. Fine drawing
Cold drawing is to use a cold drawing machine to draw a metal pipe without heating the metal. The advantage is that it does not need to be carried out at high temperature, and the disadvantage is that the residual stress is relatively large, and it cannot be pulled too long. Cold drawing can improve toughness and tensile strength to obtain better mechanical properties.
Cold drawn seamless steel pipe process:
Round tube blank→heating→piercing→heading→annealing→pickling→multi-pass cold drawing→semi-finished pipe→heat treatment→straightening→hydraulic test (flaw detection).
Two ways of cold drawing:
There are two different methods of cold working of metals. One refers to the method of applying tension at both ends of the metal material to cause tensile deformation of the material; the other refers to the method of applying pulling force at one end of the material to make the material pull out through a mold hole. The aperture of the mold smaller than the diameter of the material. The cold drawing process causes the material to have extrusion deformation in addition to the tensile deformation, and the cold drawing process is generally carried out on a special cold drawing machine. Materials processed by the second type have better properties than materials processed by the first type.
Main application: for automobiles, motorcycles, refrigeration equipment, hydraulic parts, pneumatic cylinders, and other customers who have high requirements for the precision, smoothness, cleanliness, and mechanical properties of steel pipes.
2. Finish rolling
Finish-rolled pipe is also called cold-rolled precision steel pipe, which is a production process of seamless steel pipe.
Features of finish rolled tube:
(1) The cold-rolled precision steel pipe has high tolerance and dimensional accuracy, and the product accuracy is controlled at ±0.05mm.
The inner and outer walls have good finish and no oxide layer on the surface.
(2) The comprehensive properties of cold-rolled precision steel pipes are excellent, able to withstand high pressure, cold-bending, flaring, and flattening without cracking or wrinkling, and can be subjected to various complex deformations and mechanical processing.
(3) The promotion and application of precision seamless pipes can save steel, improve processing efficiency, reduce processing procedures and equipment investment, save costs and greatly save machining hours, increase production capacity and material utilization, and help improve product quality. cut costs.
The use of finishing tube:
Cold-rolled precision steel pipes are widely used in automobiles, motorcycles, electric vehicles, pneumatic cylinders, petrochemicals, electric power, ships, aerospace, bearings, pneumatic components, medium and low pressure boilers and other fields.
No matter what kind of cold-rolled pipe, it needs annealing heat treatment, which can not only eliminate the stress generated after multiple processing, improve the mechanical properties, reduce the hardness of the material, but also form a dense protective film on the surface of the pipe to prevent corrosion. effect.
Hangao Tech (SEKO Machinery) has rich experience in heat treatment of seamless steel pipes. Over the years, it has in-depth cooperation with many customers and has accumulated a strong production database. It can provide customers with production suggestion and ensure the accuracy and yield of finished pipes. With fully air-cooled induction heating power supply, our independent seamless pipe bright annealing furnace induction heat treating machine line reduces energy consumption, improves efficiency, and prolongs the service life of equipment.
As cold-rolled pipes are more and more used in various high-end industrial fields, the demand for high-end cold-rolled pipes will also become stronger and stronger. If you have any questions about precision rolled tubes, please feel free to consult us for communication.
