The New Retractable Tubeskin Thermocouple

Thermocouple

Hot pipe and fire inside industrial furnace.

As we have said before our engineers are constantly striving to develop new ideas and products which will benefit our clients. One range of products where we already excel is our Tubeskin Thermocouples, including the Fan Type Thermocouple. But not rest on our laurels we are pleased to announce the launch of our New Retractable Tubeskin Thermocouple.

Our range of Tubeskin Thermocouples are used to monitor the temperature on the surface of pipes such as those used in heating furnaces of oil refining plants. These Thermocouples are welded in place directly to the pipe and produce excellent temperature readings, however when it comes to replacing the sensor the old one would need to be removed and the new thermocouple would need to be welded in position.

The new Retractable Tubeskin Thermocouple removes the requirement for re-welding, which is a time saving benefit meaning when the sensors need to be replaced your furnaces are down for a shorter period of time.

The retractable thermocouple works by having a detachable D-shape tip which is welded to the pipe. However, the sheath and tip can be attached without welding them together which means only the sheath would need to be replaced.

What’s more we have confirmed through in-house tests that the retractable thermocouple exhibits performance that is equivalent to our conventional fan types while eliminating the need to perform welding when replacing the temperature sensor.

Here are some key points:

  • Accuracy maintained between +4 to +6°C with and without the shield
  • The new shield design with Ceramic insulation protects against excessive radiant heat
  • A small welding footprint is maintained for easy installation
  • Fan Type tip, clips and shields can be installed before the Tubeskin thermocouple is delivered allowing flexibility for welding and NDT testing
  • Only the Thermocouple sensor needs to be ordered for the next turnaround
  • Okazaki will maintain records of the replacement Fan Type tubeskin thermocouple by referencing your Tag number.

 

To prove the accuracy of the retractable tubeskin we some comparisons against our existing Fan Type product which we already know to be among the most accurate on the market and the results were very similar between the two products.

We began by attaching the thermocouples of the surface temperature sensor to a stainless-steel box. We then kept the temperature of the stainless-steel box to approximately 500°C and raised the ambient temperature to close to 800°C. Once those parameters had been achieved we then measured each thermocouple.

 

Thermocouple Diagram

 

Here are the results of our tests:

Version Tip Temp Output Result Temp Error
Retractable 507.1°C 503.1°C +3.6°C
Fan Type 507.1°C 502.6°C +4.0°C