Identify unknown steel
Identify unknown steel
(OP)
Hi guys,
We have a project in which the refurbishment of a servomotor was given to an external company.
This equipment will only be installed for another 10 years, before a larger project will replace all the equipment in the substation.
Therefore, the company was told that no changes to the original design must be made.
The original piston removed could not be recycled and needs to be replaced by a new one.
We have asked the exact same material be used to machine the new piston.
The company therefore proceeded to the chemical composition analysis : it was determined that the original material was AISI 1040.
What other tests must be done in order to identity the original material (its state, its mechanical properties, etc)?
The equipment is installed inside, Tamb is above 10C at all times.
Thanks for your help
We have a project in which the refurbishment of a servomotor was given to an external company.
This equipment will only be installed for another 10 years, before a larger project will replace all the equipment in the substation.
Therefore, the company was told that no changes to the original design must be made.
The original piston removed could not be recycled and needs to be replaced by a new one.
We have asked the exact same material be used to machine the new piston.
The company therefore proceeded to the chemical composition analysis : it was determined that the original material was AISI 1040.
What other tests must be done in order to identity the original material (its state, its mechanical properties, etc)?
The equipment is installed inside, Tamb is above 10C at all times.
Thanks for your help





RE: Identify unknown steel
RE: Identify unknown steel
Thanks for your reply,
I am under the impression that solely measuring the hardness at the center and at the surface will not be enough to determine the heat treatment...
For example, this will give no indication as to the yield strength...
RE: Identify unknown steel
Petrotrim Services, LLC
www.petrotrim.com
RE: Identify unknown steel
Even if you perform a tensile test, however, you will not know what the original design specification was. It is quite possible that the actual yield strength determined by your test met the original design specification (often, the design will specify a yield range and all you will know is a single value). It is also possible that the actual yield did not meet the design specification, but was accepted by the manufacturer on a deviation (say, the manufacturer knew the minimum specified yield was 5 times what was necessary for this specific assembly). The actual yield strength will not tell you any of this.
What you do know is the material chemistry and, if you perform a hardness profile on a cross-section, you will have a good idea if the material was in the annealed, hardened, or case-hardened condition. At that point, you may need to perform additional tests (microstructure, for example) to fully define the processing used.
With this information, however, you will still not know what the original design was, only what material and processing will produce an acceptable part (assuming the original part gave acceptable performance).
rp
RE: Identify unknown steel