MTR Verification
MTR or Mill Test report certifies that the on-site material’s chemical analysis, mechanical properties, and manufacturer information comply/match the prescribed specification.
An MTR certifies a material’s compliance with a standard specification such as ASME Section II Part A and B or ASTM. The MTR is supplied from the material manufacturer such as plate manufacturer, casting manufacturer, forging manufacturer, etc.
Heat Number
The MTR document contains a heat number which is also known as “melt number” and is like a lot or batch number. When the steel plate is in its molten condition, a sample is drawn out from the batch for analysis of its chemical composition. This plate is given a particular identification number known as a Heat Number.
The Heat Number provides a way to trace back the steel plates to their production units and process conditions. During the inspection of the material, the heat number referenced on the MTR must match the Heat Number engraved/printed on the steel plate.
Multiple steel plates might have an identical Heat Number, and this is normal since that indicates the steel plates are made from the same batch of melted material.
Contents of an MTR
An MTR certificate should contain the following essential information:
Sigma provides MTR verification as part of the company's core competency in Third-Party Verification (Vendor Surveillance) and QA/QC review/oversight.
