4-16. Using Contact Thermocouples
The welded thermocouples discussed previously can be used for preheating or stress relieving. As an alternative, in preheating applications, a contact temperature sensor* can be used. This eliminates the need to weld thermocouples and the sensor can be moved during the preheat process to check temperatures at other locations on the joint.
.Removing the contact probe will display a short duration of heat drop on the temperature recorder, if used.
The contact temperature sensor can be plugged into the thermocouple extension cable or a Type K 25 ft. armored extension cable* can be used. One of these extensions is required for each sensor.
In preheating applications, the thermocouple must be placed under the induction coil. Temperatures at the weld joint can be checked with temperature sensitive crayons to verify the preheat temperature.
Welded thermocouples are normally used in stress relieving applications due to their accuracy.
*See product literature for item part number.
4-17. Placing Temperature Probe
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2
1Blanket
2Temperature Probe
Place temperature probe between blanket and metal material. The probe must be in contact with the material being heated. The tip of the probe should be positioned in the approximate center of the blanket anywhere along the blanket length.
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