Protection Tubes for Temperature Measuring Devices
Wherever a thermometer is exposed to high pressures or flow velocities in a medium, it is advisable to install an additional protection tube into which the measuring instrument is inserted.
Especially with dial thermometers, whose immersion tube cannot be removed, an additional protection tube is required so that you do not have to empty the process when replacing the measuring device. Our SIKA industrial thermometers are designed so that the immersion tube can remain in the process while the glass insert or casing is replaced.
Which protection tube you need depends on your intended use. If you merely want to seal off the process, a multi-part welded or soldered protection tube (brass, steel, stainless steel) is sufficient; for higher pressures and/or flow velocities, we recommend protection tubes made of solid material that can be screwed or welded in.
The choice of material for the protection tube depends on the stability and material requirements of the medium being measured, or on the material of the tube into which the protection tube is to be welded.
The compressive strength of immersion tubes and protection tubes must be determined individually for the respective application. In this case, the static and dynamic loads, medium temperature and other factors must be taken into account. Please understand that we can only provide non-binding guide values for the intended use without knowledge of the conditions on site. The technical designer of the system is responsible for ensuring correct dimensioning.
For pipes made from solid material, an acceptance test certificate in accordance with EN 10204-3.1 can be issued for higher pressures. We can carry out water pressure tests up to 160 bar in house.
Further information on the compressive loads of different protection tubes can be found in our technical datasheet "Pressure Load for immersion and protection tubes".
