Designed for use with thermocouples and rtds in large nonpressurized tanks these protection tubes are available in long lengths at a lower cost than thermowells.
Ceramic thermowell materials.
In conjunction with the appropriate thermocouple the thermowell has a considerable effect on the temperature sensor s measuring accuracy and service life.
The end of the thermowell may be of reduced diameter as is the case with a tapered or stepped shank thermowell to improve the speed of response.
Materials and construction the thermowell protects the instrument from the pressure flow induced forces and chemical effects of the process fluid.
Standard materials are recommended wherever possible.
Ceramic protection tubes are used for applications where contamination from hostile environments or the cutting action of concentrated and direct flame impingement are factors.
If a fitting other than the standard thread is required specify by adding the option code from the optional fitting table as a suffix to the part number.
Metal thermowells are available in brass carbon steel 304 and 316 ss and monel.
Steel and 316 stainless steel protection tubes are more durable than ceramic protection tubes.
Ferritic stainless steel with excellent resistance to sulphurous atmospheres at high temperature however due to its low strength at high temperature thermowells made from this material should be mounted vertically.
Thermowell materials for various average applications are listed in the following table.
Typically a thermowell is made from metal bar stock.
Used in heat treatment processes iron and steel furnaces gas production plant and it has some useful resistance to molten lead.
Select the tube size from the table and specify the part number shown for the desired material c30 or c98 replacing the l and x with the required length in inches.
Tsh220 with ceramic thermowell for temperatures up to 1800 c 3272 f.