Seamless steel pipe uses the structure of steel, so the hardness of seamless steel pipe is high. The quality of seamless steel pipe is the reason why this type of pipe material is promoted and developed in the industrial field. This is determined by the complex production process of seamless steel pipe. The characteristic of seamless steel pipe is that there are no joints in the wall of the pipe, while ordinary pipes have obvious joints.
Stainless Steel Seamless Pipe is mainly used in pipeline transportation and can be used to transport some fluids, such as energy, oil and underground water. Its area of use and range are expanding in modern society. General-purpose seamless steel pipes are rolled from ordinary carbon structural steel, low-alloy structural steel, or alloy structural steel. They have a large output and are mainly used as pipelines or structural components for conveying fluids. The seamless steel pipes made of this kind of steel are widely used in hydraulic props, high-pressure gas cylinders, high-pressure boilers, fertilizer equipment, petroleum cracking, automotive semi-axle sleeves, diesel engines and other industries.
When it comes to further use and promotion, the significance of energy transportation is significant, and seamless steel pipes play an important role in it. First, the strength is slightly higher than that of No. 15 steel and rarely undergoes quenching. It has no temper brittleness. Cold deformation has high plasticity and is generally used for bending, rolling, bending, and arch hammer processing. The welding performance of arc welding and contact welding is good. Gas welding with small thickness or strict shape requirements or complex shapes is prone to cracking. The cutting processing performance is better in cold drawing or normalizing state than in annealed state, generally used to manufacture parts with small stress and high toughness requirements. We always maintain a stock of about 10,000 tons and annual sales exceeding 100 million yuan. The products sold comply with national standards and are suitable for engineering, coal, and textile industries. What needs to be seen is the price advantage of seamless steel pipes. Although the quality of seamless steel pipes is good, the cost performance of this type of pipe material is actually very high, which are the advantages of seamless steel pipes.
The size stability of high-precision seamless steel pipes slows down the cooling speed due to the slow cooling speed of high-precision seamless steel pipes, which stabilizes the austenite and increases the residual austenite in their organization. Therefore, it must undergo cold treatment.
To reduce quenching deformation, due to the slender and narrow shape of seamless steel pipes, it is easy to deform during quenching and hardening. Therefore, its deformation must be strictly controlled. Heat treatment is a crucial process. During the quenching and cooling process, timely straightening should be done using the plasticity of the supercooled austenite. This is a critical step to ensure that its pass rate is improved. For this reason, it should be quenched in a hot bath or cooled in oil for a certain period of time to remove heat and straighten. At the same time, the heating should be suspended to reduce quenching deformation. For high-precision guides, gas nitriding or ion nitriding is carried out to reduce deformation.
High-hardness seamless steel pipes mainly bear contact fatigue loads, so they must have high hardness. Therefore, quenching, surface quenching, or chemical heat treatment should be carried out, followed by low-temperature tempering.