The material standard for the piping lists the minimum required markings for each piece of pipe. It also lists the required information to be included on the MTR.

You will constantly be fighting with this issue. Many times the markings are faded, scratched off, covered in mud or rust or just plain hard to see. You will have to draw your own line in the sand regarding what you will accept. For example, most piping is required to be hydro tested or, alternatively, NDE examined at the fabrication plant. That info is supposed to be marked on the pipe and the MTR. Sometimes, for whatever reason, it is not marked on the pipe, but it is on the MTR. You may be technically justified in not accepting the material based on the fact that it isn't marked properly. However, you may decide to accept it based on the MTR and the fact that it will be hydro tested later.

In your case, you have "un-marked" material from a plant, that the supplier stenciled with a "heat number". I would reject it outright. You don't have any idea why that heat number was chosen. It could be that the supplier had an MTR on his desk, needed to make a delivery to you; and simply stenciled that heat number on because a heat number was required.

For the material you have, you don't know what the material spec or grade is, who the mfr is, and a host of other info.

The supplier is responsible to prove to you that the material is what it's supposed to be. You are under no obligation to bend over backwards to make accomodations for his lack of traceability.

Charles

Charles is exactly right:

Regarding your specific question about manufactures marking: SA 530 requires "Each length of pipe shall be legibly marked with the manufactures name or brand, the specification number, (year of issue not required), and grade."

If the pipe is 3ft or less the markings may be transferred to a tag.

Regarding your MTR - was a "Certified Test Report" required in your purchase order when the pipe was ordered? If so there is also a list of requirements for the "Certified Test Report" in SA 530.

I'm with Charles and would reject it as non-conforming regardless of the service.

ASTM A530 is "General Requirements for Specialized Carbon and Alloy Steel Pipe". Post a fax number if you need a copy (10 pages).