Heat lot number in the above image is highlighted in red.
A heat lot number is a traceability code assigned to a specific batch of metal produced during the same melt or manufacturing run. For stainless steel sanitary fittings, tubing, valves, and related components, this number helps connect the finished part back to the material it was made from.
Heat lot numbers are commonly used by QA teams, engineers, and procurement departments to confirm material identity, support documentation requirements, and maintain traceability in sanitary processing systems. They’re especially important when a facility needs records for stainless grade, chemistry or material origin.
Why heat lot numbers matter
In hygienic processing, documentation can be just as important as the component itself. A heat lot number gives teams a way to connect a part to its supporting paperwork, often through a Material Test Report (MTR).
Here’s How to get a heat lot number
The easiest way to acquire a heat lot number is to check the documentation supplied with the product, the product packaging, or the markings on the component when available. If you need help identifying the right item, our Part Number Reference Guide can help confirm the product style before requesting documentation.
When contacting a supplier, provide the order number, part number, quantity, and any markings visible on the part or packaging. If a material test report is available for that item, the heat lot number is typically included on the report. For custom or project-specific parts, it is best to request traceability documentation at the time of quoting or ordering.
Related resources
The following video breaks down additional information that can be found on a typical Mill Test Report.
For additional information on heat lot numbers, check out this article.