The patented WIKA V-PAD^® enables the surface temperature of a tubeskin thermocouple within a combustion furnace to be measured accurately. The name V-PAD^® is derived from the shape of the sensor. It is V-shaped and enables a full penetration welded connection to be made between the sensor and the tubeskin thermocouple.

In the V-PAD^®, the flexible part of the sensor is a mineralinsulated cable (sheathed cable). It consists of a metal outer sheath, which contains the insulated internal leads, compressed within a high-density ceramic composition. The internal leads are made from thermo material. The material of the outer sheath can be selected to match the application.

At one end of the sheathed cable, the internal leads are welded together to form a non-insulated (grounded) measuring point. At the other end of the sheathed cable the ends of the leads are connected and the sheathed cable is hermetically sealed using a sealing compound.

The lead ends form the platform for the electrical connection. Cables, plug-in connectors or connector sockets can be connected to them.

Sensor design
The tubeskin thermocouple is supplied with a non-insulated measuring point (grounded). Only in this way it is possible to ensure that the temperaturesensitive measuring point is positioned as close as possible to the tube surface. By welding the V-PAD^® to the tubeskin thermocouple, the measuring point becomes part of the tube surface and provides accurate measuring results.