The high quality of
pickled and passivated seamless steel pipes is mainly manifested in dimensional accuracy and surface finish. Even after heat treatment, there will be no oxide film on the pipe surface, and cold bending will not deform, so it can be used for more complex machinery. Processing, these are the advantages of pickling passivation seamless steel pipes.
Under the action of strong external force, the plastic resistance and fracture resistance of pickling passivation seamless steel pipes have been improved to a certain extent. Because of any kind of steel pipe, the wall thickness of the steel pipe, as well as the ovality and curvature of the pipe, cannot be done. Other types of steel pipes can only reduce errors in these aspects of the pipeline.
But the pickling passivation seamless steel pipe is different. The production standard of this kind of pipe stipulates the error in this respect and cannot exceed the tolerance. If this condition cannot be met, it is a substandard steel pipe. If the customer has no special requirements, the error of the pipe wall thickness, ovality, and curvature cannot exceed 80% of the tolerance. If you have more precise requirements for the size of the pipe. Then when you order steel pipes, you can negotiate with the steel pipe factory, and you can ask the other party to further reduce the error in pipe size.
The difference between pickling passivation seamless steel pipe and welded pipe:
1. The inner wall is different: the pickled and passivated seamless steel pipe is an extruded pipe with a smooth inner wall and no welds, while the welded pipe is made of steel plate roll arc welding, and its inner wall has welds along the length of the pipe;
2. The production process is different: the welded pipe is made by crimping and welding of strip steel, and the pickling passivation seamless steel pipe is made by perforating the billet without welding points;
3. According to purpose: the pressure of welded pipe is not as high as that of pickled and passivated seamless steel pipe. Pickled and passivated seamless steel pipe can be used for fluid pipes and pressure parts above 0.8MRa; welded pipe can only be used for Fluid pipes and structural pipes below 0.8MRa;
4. According to source: pickling passivation seamless steel pipe is made by perforating and extruding steel billet; welded pipe is made by welding strip steel;
5. By value: the price of pickled and passivated seamless steel pipes is high, but the price of welded pipes is low.
6. By name: Pickling passivated seamless steel pipe is directly marked, such as Φ32*2.5 indicates that the diameter is 32 and the wall thickness is 2.5; the welded pipe is marked with the nominal diameter (nominal size)'DNXX', and the pickling passivated seamless steel pipe, For example, DN32 indicates that the diameter is 42.4 and the wall thickness is 2.75-3.94;
7. According to production capacity: the production capacity of pickled and passivated seamless steel pipes is low, and the production capacity of welded pipes is high.
Tips: API 5L line pipe transports the oil, gas or water extracted from the ground to the petroleum and natural gas industrial enterprises through the line pipe. Line pipes include seamless line pipes and welded pipes. The pipe ends have flat ends, threaded ends and socket ends; the connection methods are end welding, coupling connection, socket connection, etc.
