The production process of seamless steel pipe is a highly sophisticated and complex process which involves several key steps and quality control measures. In the following, we will introduce the production process of seamless steel pipe in detail, including raw material preparation, piercing, rolling, heat treatment, finishing and inspection.

I. Raw material preparation

The production of seamless steel pipe first needs high-quality raw materials. Usually, the main raw material of seamless steel pipe is high carbon steel, low carbon steel or alloy steel. These raw materials need to undergo rigorous testing and screening to ensure that their chemical composition and physical properties in line with production requirements. After the raw materials are prepared, they also need to be pre-treated, such as crushing, screening and mixing, to ensure the homogeneity and stability of the raw materials.

2. piercing

Perforation is one of the key steps in the production of seamless steel pipe. It is through the use of piercing machine will be solid round steel piercing into hollow hair pipe. During the perforation process, parameters such as perforation temperature, perforation speed and perforation force need to be controlled to ensure that the inner and outer walls of the burr pipe are smooth and free from defects such as cracks and folding. At the same time, it is also necessary to carry out regular maintenance and overhaul of the piercing machine to ensure its normal operation and piercing quality.

3. rolling

Rolling is the core link of seamless steel pipe production. In the rolling process, the gross tube through the mill for many times and reduce the diameter, and gradually form the required specifications of seamless steel pipe. In the rolling process, the need to control the rolling temperature, rolling speed and rolling force and other parameters to ensure the dimensional accuracy of the steel pipe, wall thickness uniformity and surface quality. In addition, the selection and configuration of the mill is also an important factor affecting the rolling quality.

4. heat treatment

Heat treatment is an important part of the seamless steel pipe production process. Through heat treatment, you can eliminate residual stress in the steel pipe, improve the organisational structure and improve mechanical properties. Common heat treatment methods include normalising, annealing, quenching and tempering. In the heat treatment process, the heating temperature, holding time and cooling rate and other parameters need to be strictly controlled to ensure that the performance of the steel pipe meets the requirements.

5. Finishing

Finishing is the last process of seamless steel pipe production. In the finishing process, the steel pipe needs to be cut, straightened, flaw detection, marking and packaging operations. Cutting operation usually adopts flame cutting or mechanical cutting, etc., to cut the steel pipe into the required length. Straightening operation is done by straightening machine to keep the straightness and flatness of the steel pipe. Flaw detecting operation is to detect the internal and surface defects of steel pipe by ultrasonic or eddy current methods. Marking is done to mark the pipe with information such as specifications and production batch. Finally, the steel pipe needs to be packaged to prevent damage during transport and storage.

6. Inspection

Inspection is a key link to ensure the quality of seamless steel pipe. In the production process, each link needs to be strictly inspected and controlled to ensure that the quality and performance of steel pipe meet the standard requirements. Common inspection methods include chemical composition analysis, mechanical properties testing, metallographic observation, non-destructive testing and so on. At the same time, it is also necessary to carry out regular maintenance and overhaul of production equipment to ensure its normal operation and production quality.

In summary, the production process of seamless steel pipe is a highly precise and complex process that requires the synergy of multiple links and quality control measures. By strictly controlling the quality of raw materials, optimising the piercing and rolling process, reasonably selecting the heat treatment method and finishing process, as well as strict inspection and control measures, high-quality seamless steel tubes can be produced to meet the needs of various industrial fields.