Both the thermowell materials temperature resistance and their resistance to aggressive media are decisive.
Ceramic thermowell materials.
Tsh220 with ceramic thermowell for temperatures up to 1800 c 3272 f.
Metal thermowells are available in brass carbon steel 304 and 316 ss and monel.
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.
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.
Thermowell materials for various average applications are listed in the following table.
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.
Steel and 316 stainless steel protection tubes are more durable than ceramic protection tubes.
Standard materials are recommended wherever possible.
The list has been carefully prepared and takes into consideration such factors as contamination electrolysis catalytic reaction and other variables.
Typically a thermowell is made from metal bar stock.
Ceramic protection tubes are used for applications where contamination from hostile environments or the cutting action of concentrated and direct flame impingement are factors.
Materials and construction the thermowell protects the instrument from the pressure flow induced forces and chemical effects of the process fluid.
Used in heat treatment processes iron and steel furnaces gas production plant and it has some useful resistance to molten lead.
316 stainless steel protection tubes are extremely resistant to corrosive chemicals and they can handle higher temperatures than steel.