Tempil MRK28031 Temperature Indicators Tempilstik 177 C/350 F

The Tempil MRK28031 is a Tempilstik temperature indicator, 177°C / 350°F, 10 per case.

A Tempilstik is a crayon formulated to melt at one precise, calibrated temperature and it solves a problem that sounds trivial and is not: knowing how hot a piece of steel is.

Mark the metal with the stick. Below the rated temperature the mark stays chalky and dry. At the rating it melts to a liquid smear. That transition is the measurement, and it happens at the surface being welded rather than wherever a probe happens to touch.

Why it matters is metallurgy. Welding preheat slows the cooling rate of the heat affected zone, and cooling rate is what determines whether the steel transforms to a hard, brittle martensitic structure. Combine that hardness with the hydrogen that welding introduces and the result is hydrogen-induced cracking — cracks that appear hours or days after the weld is finished, in a joint that passed inspection. Preheat is the control, and 350°F is a common requirement on heavier sections and higher-carbon steels.

The procedure exists because the failure is delayed and invisible. Nobody sees a hydrogen crack form.

The 10 per case quantity is shop packaging.

Applications include welding preheat verification, structural steel, and pipe fabrication.

Brand

Tempil

SKU

MRK28031

Category

Painting & Marking Supplies

Weight

0.4 lbs

Dimensions

5.50 x 0.60 x 0.60

Price

$22.95

Availability

In stock

Rating

0 / 5.0