The production process of longitudinal seam welded steel pipe involves several crucial steps, which are detailed below:
1. Material Preparation
- Suitable steel strips are selected, ensuring their thickness, width, and material meet production requirements.
- The steel strips are cut to the desired length and width, and surface oxides are removed to ensure welding quality.
2. Roll Forming
- The steel strips are placed on a roller conveyor.
- Through pre-bending and roll-forming processes, the steel strips are shaped into the desired tubular structure.
3. Welding
- The formed steel strips are welded longitudinally, usually using high-frequency welding or electric resistance welding, to form a continuous tubular structure.
- This welding process ensures the sealability and stability of the steel pipe.
4. Weld Treatment
- Visual inspections are conducted on the welded areas to ensure there are no issues such as missing welds or incomplete fusion.
- Internal quality inspections are also carried out to detect defects such as pores or slag inclusions.
5. Size Verification
- Finished longitudinal seam steel pipes undergo size measurement and verification to ensure they meet design requirements and standards.
6. Surface Treatment
- The steel pipes undergo cleaning, rust removal, and corrosion prevention treatments to improve their appearance and corrosion resistance.
7. Quality Control and Testing
- Throughout the production process, various quality control measures are implemented to ensure the quality and performance of the steel pipes meet expected standards.
- Tests such as ultrasonic testing, X-ray inspection, and hydrostatic tests may be conducted to further verify the integrity and strength of the steel pipes.
8. Packaging and Delivery
- The steel pipes are packaged to ensure safe and stable transportation and storage.
- Factory inspections and deliveries are conducted to ensure the quality meets customer requirements.
Types of Longitudinal Seam Steel Pipes
- High-frequency Longitudinal Seam Steel Pipe: Welded using high-frequency welding technology.
- Submerged Arc Longitudinal Seam Steel Pipe: Welded using submerged arc welding, which can be further divided into different types based on their forming methods, such as UOE, RBE, and JCOE.
In summary, the production process of longitudinal seam welded steel pipe involves multiple steps, each of which is crucial to ensuring the quality and performance of the final product. By strictly controlling the production process and implementing quality control measures, high-quality longitudinal seam steel pipes can be produced to meet market demands.
