Wear-resistant thermocouple tube material classification and selection of different materials

Wear resistant thermocouple tube material mainly are divided into high temperature alloy, compound casting wear-resistant alloy and ion permeability tungsten carbide three injection.

1, wear-resistant high temperature alloy: according to the environment of high temperature wear characteristics, specially designed pure alloying by vacuum smelting, high temperature oxidation resistance and high temperature strength of special wear-resistant high temperature alloy, the forging overall drilling. Processing less defect and high reliability, high temperature strength wear-resisting comprehensive performance is good, price is higher, temperature 800 ~ 1200 ℃.

2, compound casting wear-resistant alloy: adopt composite armor technology to join particle wear-resisting, high temperature alloy matrix precision casting molding. Without turning processing, casing high hardness, resistance to high temperature oxidation, but with a little casting defects do not affect high temperature wear resistance and impermeability, is the most common use of high temperature resistant casing, price moderate, temperature 800 ~ 1200 ℃.

3, ion permeability tungsten carbide: for stainless steel substrate by ion permeability injection technology on the surface casing injection of tungsten carbide particles. Hard, high strength, high Gao Ren, special wear-resisting, wear-resisting layer thickness of 0. 5 ~ 1. 5 mm, rigid toughening, minimum diameter to & phi; 8, good surface quality, use temperature 0 ~ 800 ℃. The service life of up to 2 years in power plant coal mill selection thermocouple, please see the thermocouple with insulation material, under the high temperature, the insulation resistance rapid decrease with the temperature increasing, therefore, there will be a leakage current, the current through insulation insulation resistance had fallen into the instrument, the instrument instability or measurement error, may also occur dot recorder disorderly phenomena.

select thermocouple please see its material:

thermocouple with insulation, under high temperature, the insulation resistance rapid decrease with the temperature increasing, therefore, there will be a leakage current, the current through the insulation of the insulation resistance has fallen objects into the instrument, the instrument instability or measurement error, may also occur dot recorder disorderly phenomena.

thermocouple is the most broadly used in the field of global industrial temperature measuring device, which belongs to a kind of precision instruments, therefore, to measure the accurate numerical value, first of all need to be put into the proper atmosphere, so to get the measured value of the good, must not forget that in the process of operation.

in the outside of the thermocouple is a special material layer of protection. For heat pipe appearance, different capable person for the service life of heat pipe also has close relationship with the environment. Such as its wear-resisting cut the thermocouple protection tube, it will need to use special heat-resistant and wear-resistant alloy material as outside temperature protection tube, built-in armored core body, both has the high corrosion resistant performance of particle erosion, and under the condition of high temperature on the inner core body can play a good protective effect. Can adopt the flanged or threaded connection, between 0 ∽ 1200 ℃ temperature measurement for a long time.

everybody when selecting a thermocouple, be sure to see exactly what kind of material of thermocouple. For the thermocouple of compound casting wear-resistant alloy material, the adopted technology of the other is to use compound armored techniques to join particle wear-resisting, high temperature alloy matrix precision casting molding. Without turning processing, casing high hardness, resistance to high temperature oxidation, but with a little casting defects do not affect high temperature wear resistance and impermeability, is the most common use of high temperature resistant casing, price moderate, temperature 800 ~ 1200 ℃. Even though

is a thermocouple, although belong to special heat-resistant type thermocouple, but is because of these two kinds of material is a kind of wear resistant alloy, the other one is using the technology of compound metal clad, in its application and the price has been very different. In the two different thermocouple, technical parameters and the application scope, can give reference to manufacturers specifications, as one of the best.

for prefabricated thermocouple, the influence of atmosphere, first of all depends on the protecting tube material and structure of the thermocouple, therefore, be familiar with and master all kinds of protection tube materials of physical and chemical properties, it is very necessary. Commonly used in powder metallurgy industry, for example, molybdenum tube as the thermocouple protection tube. Under the 1600 ℃ of H2 atmosphere, good use effect. However, molybdenum tube under oxidizing atmosphere, a very short time because of oxidation and erosion. Second, should be used according to the atmosphere, select the appropriate thermocouple, in above 1300 ℃ in the oxidizing atmosphere, choose platinum rhodium thermocouple, under the condition of reducing, vacuum using tungsten-rhenium thermocouples is better.

for K type thermocouple, suitable for working in the atmosphere, such as air, O2, but when used in H2, its surface is H2 reduction, a short period of time without the influence, if long time exposure in H2, at the same time of speed reduction, would make silk grain growth and occasionally break line; In reducing atmosphere like CO or gas, and its degradation will significantly speed up the difference.

for armoured thermocouple, hydrogen atomic radius is small, easy to through the coat into its interior, also will accelerate the degradation, the thermoelectric potential value of slash.