What is a cold-drawn seamless pipe?

1. What is a cold-drawn seamless pipe?
The difference between cold-drawn seamless pipe and hot-rolled pipe is that it is a steel pipe material with high precision and good surface finish. It is produced by cold drawing process and has a hollow cross-section and round, square or rectangular steel with no seams around. This kind of steel pipe is mainly used in mechanical structures, hydraulic equipment and other fields. Because of its high dimensional accuracy and good surface finish, the use of precision seamless pipes to manufacture mechanical structures or hydraulic equipment can greatly save machining time, improve material utilization, and help improve product quality.
The production process of cold-drawn seamless pipe includes the production of a whole steel pipe using drawing, extrusion, perforation and other methods, and there is no seam on the surface. It is made of steel ingots or solid tubes through perforation to make rough tubes, and then cold drawn. This kind of steel pipe material plays an important role in the industrial field, especially in occasions where high precision and high quality are required. ‌
In addition, the precision cold-drawn tube (precision drawn tube) is a kind of cold-drawn seamless tube. It is a high-precision steel tube material that uses cold-drawn seamless tube as raw material for tolerance control and surface bright processing. This steel tube material is widely used in various fields requiring high precision and high reliability due to its high precision and excellent surface quality.

2. The difference between cold-drawn seamless tube and hot-rolled tube
The main difference between cold-drawn seamless tube and hot-rolled tube lies in their manufacturing process, materials and performance, application fields, manufacturing difficulty and cost. ‌

Manufacturing process: The cold-drawn seamless tube is made by passing the steel billet through a hole with a certain specification of round holes, and gradually reducing the pipe diameter and increasing the wall thickness through multiple drawing and annealing treatments. The hot-rolled seamless steel pipe is made by continuously rolling the steel billet through multiple rollers at high temperature, so that the steel billet is gradually deformed and thinned, and finally forms a seamless steel pipe of the required specifications. ‌

Materials and properties: Cold-drawn seamless pipes are generally made of high-carbon steel or alloy steel, with high strength, hardness and fatigue resistance, but relatively poor toughness. Hot-rolled seamless steel pipes are made of low-carbon steel or low-alloy steel, with low strength and hardness, but good toughness, and are easy to process and weld. ‌

Application areas: Cold-drawn seamless pipes are mainly used to manufacture pipes and mechanical parts for high-precision, high-pressure, high-temperature and special medium transportation, such as automobile transmission shafts, turbine engines, high-pressure vessels, etc. Hot-rolled seamless steel pipes are mainly used to manufacture some structural parts and fluid transportation pipelines that do not require high strength but require good toughness, such as building structures, boilers, water and gas pipelines, etc. ‌

Manufacturing difficulty and cost: The manufacturing process of cold-drawn seamless pipes is complex, requiring multiple drawing and annealing treatments, a long production cycle, and low output, so the manufacturing cost is high. The manufacturing process of hot-rolled seamless steel pipes is relatively simple, with a short production cycle and high output, so the manufacturing cost is relatively low. ‌

In summary, there are obvious differences between cold-drawn seamless pipes and hot-rolled seamless steel pipes in many aspects. The choice of which type of seamless pipe to use mainly depends on the specific application requirements and cost considerations.