We Super Steel Manufacturing Co.,Ltd(SMC) are amongst the top manufacturers and suppliers for the seamless steel pipe, welded steel pipe, OCTG products and fittings from China. We have been manufacturing and supplying these products to the industry since 1993, and received repeat orders and appreciation from our valued customers.
High quality piping products from approved manufacturers.
In order to continuously improve our offerings to our clients, we have consistently improved and upgraded our manufacturing facility and can hence offer material with stringent requirements.
Over the years, Super Steel Manufacturing Co.,Ltd(SMC) has developed an enviable reputation for project management for the Oil & Gas, Construction, Power Energy, Marine & Offshore, Water Treatment, Exploration & Drilling Services, Pipeline & Petrochemical and other heavy industries.
The many years of experience that we have means that there is always someone who has the ability to carry a project forward.
Always up to date. In this column you can find the steel pipe related articles, including industry trends, product standards and materials, and some technical guidelines.
The manufacturing of large diameter LSAW (Longitudinal Submerged Arc Welding) steel pipes typically employs various molding methods, including UOE, row roll forming (CFE), and CE molding. A critical step in the majority of these processes is the final post-weld tube expansion, which ensures the pipe's shape and enhances the quality of the welded steel. Tube expansion has become an essential process in the production of large-caliber longitudinal welded pipes to guarantee the final product's quality.
Expanding Process Overview
The expanding process uses hydraulic or mechanical pressure to force the pipe wall outward, radially enlarging the diameter of the pipe. Mechanical expanding is often favored over hydraulic methods due to its simpler setup and higher efficiency. This method is widely adopted in modern systems for large-caliber longitudinal pipes. The expanding process occurs as follows: mechanical expanding involves radially expanding the pipe in segments along the pipe's longitudinal direction, causing the entire length of the pipe to undergo controlled plastic deformation. This process consists of five distinct stages.
- Initial Full Circle Stage:
In this phase, the pipe's expansion segments are opened until they make contact with the pipe wall. At this point, the radius at various points within the steel pipe becomes nearly identical, and the pipe begins to take on a circular shape.
- Nominal Inside Diameter Stage:
As the segments continue expanding, their movement slows down to ensure precise control. The segments expand the pipe until the desired nominal inside diameter is achieved. This diameter meets the dimensional quality standards required for the finished pipe.
- Springback Compensation Stage:
After the nominal diameter is reached, the segments are expanded slightly further to compensate for any springback that might occur when the pressure is released. This additional expansion ensures that the pipe maintains its final shape and meets circumferential tolerances.
Continuation of the Expanding Process
- Final Calibration Stage:
At this stage, the segments fine-tune the expansion, focusing on any remaining deviations in the pipe's diameter. This process ensures that the pipe's internal diameter meets the required specifications with minimal variation along the entire length of the pipe.
- Release and Inspection Stage:
After the final expansion, the pressure is gradually released, and the pipe is carefully inspected for any defects. This step ensures that the pipe's dimensions and roundness are consistent with quality standards. Any issues found during this inspection may require additional adjustments or reprocessing to meet specifications.
This expanding process, particularly when performed using mechanical methods, is crucial in producing large-diameter LSAW steel pipes that meet stringent quality standards for shape, size, and structural integrity. By controlling each stage of the process, manufacturers can produce pipes with high precision and durability, suitable for various demanding applications in industries such as oil and gas, water transportation, and structural engineering.
English
Español
Français
بالعربية
