Valve - hardness test

[terrysi144]

Dear collegue,

In our bid document mentioned for hardness test for valves and pipings. this bid document was created by our consultant. Is it a common requierement to ask such test ? How do that such test ? .

thanks you
terry

 

[SPDL310]

Yes this is a common practice for piping and valves manufactures. The hardness of a material is related to its yield strength and is traditionally performed my making a small indention in a non-critical area of a part like the flange OD, and measuring the amount of force required to make the indention. There are also NDE techniques which utilize other methodologies, and don't leave indentions. The purpose of this is to ensure that the specified material and yield strength has been provided, and heat treated properly. Many clients have started to request PMR (positive material recognition) testing as well in order to verify the chemical composition is correct to the specified material.

 

[terrysi144]

Thanks you for the explanation,

Regards
terry

 

[jbeckhou]

Hardness is related to tensile not yield strength. If the part comes in contact with well bore fluid and required to meet NACE, hardness testing is required and controlled by PSL - API-6A guidelines.

Petrotrim Services, LLC

http://www.petrotrim.com

 

[terrysi144]

Dear jbeckhou,

I appreciate for additional clarification

Regards
terry

 

[hsbcn]

Hardness tests can be done by using a Brinell Hardness Test. This gives you the tensile strength at the measurement point.

I work with valves in exotic alloys at alloy-valves.com. This is our blog, and this is me on Twitter and LinkedIn. Let's connect!

 

[terrysi144]

Dear HSBCN,

Thank you for valuable explanation

regards
terry

 

[jaydeep29]

API 6A 20th ed.
Maximum hardness
Material Maximum hardness
Soft iron - 56 HRB
Carbon and low alloys - 68 HRB
Stainless steel - 83 HRB
Nickel alloy UNS N08825 - 92 HRB

*Other CRAs Hardness shall meet manufacturer's
written specification.




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