Bimetallic thermometers are thermometers that use bimetallic plates as temperature sensing elements and are widely used in the measurement and control of machinery, chemical industry, light textile, pharmaceutical, food, ship and other production processes. The electrical contact series can send an electric signal when the working temperature reaches or exceeds a given value. It can also be used as a circuit contact switch in the temperature control system. Anticorrosion type is made of stainless steel, suitable for neutral corrosive liquid and gas.
An overview of the
The main component of industrial bimetallic thermometers is a multilayer sheet of metal made of two or more metal sheets stacked together. An instrument capable of recording changes automatically and continuously. To improve the sensitivity of temperature measurement, a metal sheet is usually made into a spiral roll. When the temperature of the multilayer sheet metal changes, each layer of metal expands or contracts in different amounts, causing the coil to roll up or loosen. Because one end of the coil is fixed and the other end is connected to a freely rotating pointer, the two metals have different body changes when the temperature changes, so they bend. When one end is fixed, the other end moves with the change of temperature, and the displacement is almost linear with the temperature. The recording system consists of a recording clock and a recording pen. The recording pen is connected to the amplifying lever and is controlled by an induction element. Therefore, when the bimetallic sheet feels the temperature change, the pointer can indicate the temperature on a circular scale. This instrument measuring temperature range is 200 ~ 650 ℃, allow for scale about 1% of the two processes. The thermometer is similar to a bar glass liquid thermometer, but can be used with higher strength requirements.
The principle of
Bimetallic thermometers work on the principle that two different metals expand differently when temperature changes. The main component of industrial bimetallic thermometers is a multilayer sheet of metal made of two or more metal sheets stacked together. In order to improve the sensitivity of temperature measurement, metal sheet is usually made into spiral coil shape. When the temperature of the multilayer sheet metal changes, each layer of metal expands or contracts in different amounts, causing the coil to roll up or loosen. Since one end of the coil is fixed and the other end is connected to a freely rotating pointer, the temperature can be indicated on a circular scale when the bimetallic strip feels the temperature change. This instrument measuring temperature range is 200 ~ 650 ℃, permissible error are two process about 1% of the scale. The thermometer is similar to a bar glass liquid thermometer, but can be used with higher mechanical strength requirements.
application
Bimetal thermometer is a kind of field instrument suitable for measuring medium and low temperature, which can be used to directly measure the temperature of liquefaction and gas. Instrument shell adopts anticorrosion materials, its temperature resistance can be as high as 200 ℃, the lowest for - 40 ℃. Flanged structure, double seal rubber rings, therefore anti - corrosion, good waterproof performance. The protective tube is welded with fully automatic argon gas protective tube, the weld is firm and the intercrystalline corrosion is small. The scale plate is aluminum oxide printing plate, the surface is clear and beautiful. The pointer is internal adjustable. Bimetallic thermometer with axial, radial and universal type, etc., can be directly measured in the process of various production - 80 ℃ ~ + 500 ℃ within the scope of liquid, steam and gas medium temperature.
The main features
1. Display temperature on site, intuitive and convenient; Safe and reliable, long service life;
2. Various structural forms can meet different requirements.
Technical parameters
Implement standard JB/ t8803-1998 gb3836-83
Nominal diameter: 60,75,100,150
Precision grade :(1.0), 1.5
Thermal response time: less than or equal to 40S
Protection class: IP55
Angle adjustment error: Angle adjustment error should not exceed 1.0% of its range
Return: the return of a bimetal thermometer should not be greater than the absolute value of the basic error limit
Repeatability: the repeatability limit of a bimetal thermometer should not exceed 1/2 of the absolute value of the basic error limit
Use and maintenance of bimetallic thermometers:
1. During the storage, installation, use and transportation of bimetal thermometers, collision protection pipes should be avoided as far as possible. It is strictly prohibited to twist the meter case when installing.
2. The instrument should be in - 30 ℃ ~ 80 ℃ environment temperature in normal work.
3. The temperature at which the instrument often works should be between 1/2 and 3/4 of the scale range.
Bimetallic thermometer temperature range: - 80 40 ~ + 80 ℃ ~ + 40 ℃ - 0 0 ~ 50 ℃ ~ 100 ℃ 0 ~ 100 0 0 0 ℃ ~ 150 ℃ ~ 150 ℃ ~ 200 ℃ 0 ~ 200 0 0 0 ℃ ~ 300 ℃ ~ 300 ℃ ~ 400 ℃ 0 ~ 400 0 0 0 ℃ ~ 500 ℃ ~ 500 ℃ ~ 600 ℃.
