A thermowell serves a specific function of shielding thermocouple elements from corrosion and damage that may be caused to them. They are of various types and made out of different materials for one to choose from. Choosing should be however based on the intended job specification.
While selecting the material to use for the thermowell, first of all determine the corrosive condition to which the well may be exposed. Almost all wells are given high mirror polish which serves the function of enhancing their capability to corrosion resistance. However, in most cases its used to boost their strength more than the corrosion factor. Choosing should therefore be done with an expert because for instance a high water pressure service may need a well out of stainless steel, but from a different point of view involving corrosion, a brass well is more suitable.
A readily weldable material is used in the making of the threaded wells. J or V groove design is the one used in the welding of flanges for standard flanged wells. They are also welded on both back and front sides. You may as well choose to use the double welded flanges which are of full penetration.
Constructions that are double welded have an advantage because the risk of having stress cracking or crevice corrosion is reduced. The installation of socket weld is usually simple and cannot take a lot of time in doing so. They however have to fit standards of ASA for flanges and socket weld. Installation will as a result become tight and clean.
One may choose to use a straight or tampered thermowell for their fittings. The tampered kind provide greater strength and at the same time do not sacrifice sensitivity. They therefore provide more resistance to vibrations of high frequency thus operate better with fluids of high velocity.
The straight kind of thermowell works better with fluids having a lower velocity. Charts on velocity rating can really help when you are choosing the well. They also offer other important information on designs.
There are different alloys which can be used with the various thermowells available. The material to be used should as well be able to withstand high thermal conductivity. It needs to also endure the process environments and have a low porosity to the gases. An internal hydrostatic test is first done on the materials before they are sold so that its ascertained that there will be no pressure failure.
If you are looking for the best thermowells take a look at Quality Control Thermowells. Discover why we offer unique and exceptional products when you visit http://www.qcthermowells.com today.
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