Which standard does a 1-inch pipe with an outer diameter of 25.4 follow?
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Dear all, according to the standards we usually refer to, the outer diameter of DN25/1-inch pipes as specified in GB/ASME/JIS is between 33 and 34. However, for a batch of pipes purchased overseas recently, the outer diameter of the 1-inch pipes is 25.4. Which standard is this following? Does anyone knowledgeable know? Thank you.
Check the standards specified in the material certificates, as well as whether it is structural steel pipe or process pipeline steel pipe. API 5L is 25.4.
It’s steel pipe for process pipelines; we purchased pipes that have undergone EP treatment from abroad. The equipment flanges specified by the design institute were chosen according to HG20615. It was only then that we realized there is a significant difference between the outer diameter of 1-inch pipes according to domestic standards and that of the 1-inch pipes we bought before… The problem now is to find out which standard corresponds to these 1-inch pipes with an outer diameter of 25.4, as well as which flange standard applies, so that we can determine whether they can be connected together. My experience is limited; I would be grateful for your guidance.
What is EP treatment? Apply a rubber coating on the outside of the pipe? Go and find the actual product; it will have the factory markings for the pipelines on it ； Or find the inspection report and see what it says. Abroad, the scope is too large.
I really haven’t seen it before; is it based on the inner diameter standard?
Process pipeline for electrolytic polishing. All the standards found are ASTM material standards; no size standards were found
Got it; this is a instrumentation pipe, not a process pipe. It cannot follow the process pipeline standards.
This is the difference between TUBE and PIPE as defined in standard specifications. The 1 inch referred to by your client, which corresponds to 25.4 mm, should be considered a TUBE – it is primarily used in instruments and pressure vessel equipment for applications such as heat exchange tubes. EP, as mentioned earlier, refers to electropolishing. Our company specializes in providing such products to companies in the semiconductor industry, including those like Samsung; high standards are required regarding the cleanliness and surface roughness of both the inner and outer surfaces of these pipes.