Bimetallic thermometer is a kind of measurement in the field of low temperature test instrument. Can be directly measured in the process of various production - 80 ℃ to + 500 ℃ within the scope of liquid steam and gas medium temperature. At the scene of the bimetallic thermometer display temperature, intuitive and convenient; Safe and reliable, long life; Many kinds of structure forms, can meet different requirements.

(1) the problem

Cause of pointer thermometer, and three hours of electrolyte, electrolytic cell of chromium plating with a titanium tube 1 protection tube bimetallic thermometer is 120 ° I don't have a mobile business? Corrosion of bimetal strip temperature, surface does not make the cold and hot plating chromium heat treatment is hard to know.

(2) to analyze problems

It is hard to precious metal corrosion of titanium, electrolysis, this kind of phenomenon is very obvious reason is that the purity of titanium is not enough. However, in the market to buy a bimetallic thermometer protecting tube high purity titanium is relatively difficult, high cost.

(3) solution

And corrosion resistance, and it is in a jacket or titanium protection pipe of the electrochemical protection is difficult, what material? Plastic pipe

(4) application, the effect

Shows, the corrosion resistance of plastic pipe is better than that of pure iron, mild steel at 120 ℃, good heat insulation, light weight, cheap, resistant. Bimetallic thermometer find plastic pipe inner diameter 12 mm, this is 12 mm. 510 mm long, so, at the other end of the hot pressing adhesive plastic pipe 500 mm under protection. The mercury thermometer with the thermal inertia of about 10 seconds of the water bath, plating temperature changes, to slow due to changes in the temperature of the electrolytic cell, compared to global warming, a measure of the thermal inertia is negligible. The good news is that, from 1995 up to now, in 13 years, and these, prove that this method is effective, has been in operation. In the future, we haven't tried this kind of method, if a similar situation occurred.

In the selection of bimetallic temperature time, we must give full consideration to the practical application environment and requirements, such as the dial diameter, precision grade, fixed installation way, risk categories and measured medium environment, etc. In addition, also attaches great importance to the performance and maintenance workload and other factors. In addition, the bimetallic thermometer in the process of transportation, installation and use, should avoid collision sheath maerial of temperature, in order to ensure the precision of measurement, sheath maerial brush into the length of the measured medium should be not less than two-thirds of the length of the sheath maerial, banned twist instrument shell during installation.