Analysis of key factors affecting the outer diameter accuracy of hot-rolled square tubes

The outer diameter accuracy of hot-rolled square tubes is an important indicator for measuring product quality, and its accuracy level mainly depends on the following key factors:

 

 

1. Customer needs and technical standards

The primary determinant of outer diameter accuracy is the specific requirements of customers for products. Different application scenarios have clear standards for the outer diameter tolerance range of seamless tubes, and the manufacturer needs to adjust the process parameters according to customer needs.

 

2. Sizing equipment performance and accuracy

Equipment type: The outer diameter accuracy of hot-rolled square tubes with longitudinal sizing can usually be controlled at around 1%, while oblique rolling sizing technology can achieve higher accuracy (up to 0.5%).

Equipment status: The mechanical wear, transmission system stability, and mold accuracy of the sizing machine will directly affect the outer diameter tolerance, and regular maintenance and calibration are required.

 

3. Process system and temperature control

Rolling temperature: Too high temperature will cause excessive shrinkage of the steel pipe after cooling (negative deviation is prone to occur), and too low temperature may cause positive deviation to exceed the standard.

Dynamic adjustment: According to the material, specification, real-time temperature, and die wear of the steel pipe, the rolling parameters should be dynamically optimized to ensure dimensional stability.

 

4. Material properties and deformation behavior

The thermal expansion coefficient and cooling deformation rate of different grades of steel during hot rolling are different, and the process needs to be adjusted in a targeted manner to reduce dimensional fluctuations.

 

Three core requirements of anti-corrosion coatings for coatings

To ensure the long-term durability of anti-corrosion steel pipes in harsh environments, the coating must meet the following properties:

 

• Excellent corrosion resistance

The coating must withstand corrosive media such as acid, alkali, salt, and chemical atmosphere without dissolution, swelling, or harmful chemical reactions.

 

• Excellent impermeability

It can effectively block the penetration of moisture, gas, and chemical media to prevent corrosion of the substrate.

 

• Strong adhesion and flexibility

The coating must have high mechanical strength to avoid peeling due to pipeline vibration or slight deformation, and ensure long-term protection.

 

Conclusion

The outer diameter accuracy of hot-rolled square tubes is the result of the synergy of equipment, process, materials, and customer needs. Product consistency can be significantly improved by optimizing sizing technology, strict temperature control, and equipment maintenance. At the same time, high-performance anti-corrosion coatings are the key to extending the life of steel pipes. We are committed to providing customers with high-precision, corrosion-resistant customized pipe solutions. Please contact our technical team for detailed support! Email:judesteel@juqing.hk