What are the commonly used protective tube materials of wear resistant thermocou

Wear resistant thermocouple in the use of power plants and cement plants, I believe we all know. In the temperature measurement of circulating fluidized bed, fluidized bed furnace, cement rotary kiln flue gas chamber and other occasions, the thermocouple will be scoured by granular material. If there are more particles and strong scouring force, the common thermocouple protection tube will be worn in a short time, which will improve the material requirements of thermocouple protection tube. Therefore, special material and structure thermocouple must be used in these occasions, and the tube wall needs to be thickened, which can increase the service life of thermocouple. These special materials and structures of thermocouples are wear-resistant thermocouples. Wear resistant thermocouple can be divided into the following three types according to the material of wear-resistant sleeve, and each type has its own unique characteristics

1. Wear resistant superalloy:

According to the characteristics of high temperature wear environment, this kind of material is made of pure alloying and vacuum smelting. It is a special wear-resistant superalloy with high temperature oxidation resistance and high temperature strength. It is forged and drilled as a whole. It has the advantages of less machining defects, high reliability, good high temperature strength and wear resistance, high price and service temperature of 800-1200 ℃.

2. Composite casting wear-resistant alloy:

The composite casting wear-resistant alloy adopts the composite armor technology, and the high-temperature alloy matrix is added with wear-resistant particles, and the precision casting is formed. The casing has high hardness, high temperature oxidation resistance and a few casting defects, but it does not affect the high temperature wear resistance and sealing performance. It is a common high temperature wear-resistant casing with moderate price and operating temperature of 800-1200 ℃.

3. Tungsten carbide by ion implantation

The material is made of stainless steel and tungsten carbide particles are implanted on the surface of the casing by ion implantation. It has high hardness, high strength, high toughness and special wear resistance. The thickness of the wear-resistant layer is 0.5-1.5mm, the outer hard and the inner tough. The diameter can be up to φ 8. The surface quality is good. The service life of the mill in power plant is more than 2 years.

According to different application occasions, choosing different materials of wear-resistant thermocouple can better adapt to the working environment of the site, so as to better complete the temperature measurement requirements, so as to ensure the normal production and operation of the user.