1981/04/06 Caterpillar

When heat is used to assemble or make repairs to equipment in the service shop, it is some times necessary to measure or control the temperature of the parts. For example, bucket adapters need to be pre-heated to a specific temperature before they are welded to the bucket. Or, some welding operations have to be done near parts with low tolerances to high temperatures, such as bearings, seals, or wiring harnesses. In both examples, some method of temperature measurement is needed to prevent damage to these parts.

The Tempil Division of Big Three Industries, Inc., has many heat-indication products available which can be used in the dealer's service shop. Four of these products, Tempilstiks®, Tempil Pellet®, Tempilaq® and Tempilabels® are especially important to the serviceman for temperature measurement. In a typical application, A Tempilstik® (Illustration 1) with the desired melting point (point at which the material becomes liquid) is used to make a mark on the surface of the part (Illustration 2). When the part is heated to the rated melting point of the Tempilstik®, the mark immediately becomes liquid.

Illustration 1. Tempilsticks are available with variety of melting points.

Illustration 2. Tempilstick being used to measure preheat temperature of metal part before welding.

Tempil Pellets also melt at a specific temperature. Tempil Pellets are small disks of heat-sensitive material which can be put on top of a part before it is heated. They provide a safe and accurate method to check the temperature of heat-treat operations or any other operation where the Tempilstik can not be used.

Tempilaq® is a heat sensitive paint which can be brushed on the part. It also becomes liquid at the rated melting point. Tempilstiks, Tempil Pellets, and Tempilaq are available with melting points in various increments from 38°C (100°F) to 1371°C (2500°F). Tempil Pellets are available with melting points up to 1649°C (3000°F).

Finally, Tempilabels (Illustration 3) can be used to check temperatures in lower ranges than the other products. Tempilabels are made from paper and they have an adhesive material on the back so they can be put directly on a part in any position. The center of the Tempilabels become black as the part is heated to the rated temperature shown below each circle or square. Tempilabels are available for temperature measurement from 38°C (100°F) to 316°C (600°F), and can be used to check temperatures of hydraulic oil tanks, air intakes/exhausts, housings, lines, etc.

Illustration 3. Tempilabels.

The Tempil Division home office is located at the following address:

There are several other companies which make similar heat indication products. Dealers can check with their local welding equipment supplier for details.