Of the principles and characteristics of the pressure type thermometer is what?

In daily life, a simple thermometer are familiar, such as, bimetallic thermometer, because it may be used, whether at home or factory can see chemical field, therefore, its use, principle, characteristics and so on are all very understand, here to say a very special thermometer, along with the development of the industry, its application is more and more widely, it is the pressure type thermometer. Its basic structure is made up of bulb, capillary and indicator of three parts. It is one of the earliest methods of temperature control applied in the production process, is currently the most widely use scope, performance is one of the most comprehensive mechanical thermometer table. The principle of the thermometer is based on the sealing temperature measurement system and saturated vapor pressure of liquid evaporation in the change of the relationship between temperature, and temperature measurement. When bulb feel temperature, saturated vapor produced the corresponding pressure in the closed system, cause the change of curvature elastic element, make its produce a shift in the free end, again by the displacement amplification mechanism of gear into the indicated value. The characteristics of pressure type thermometer many: the advantage of pressure type thermometer is: simple structure, high mechanical strength, not afraid of vibration. Price is low, does not need external energy, it has a phial of small size, fast response, high sensitivity and direct reading characteristics, almost set the glass rod thermometer, bimetallic thermometer, all the advantages of the gas pressure type thermometer,. Defect is: limited temperature range, generally in - 80~400℃； Heat loss due to slower response time; Instrument sealing system ( Bulb, capillary, spring tube) Damage is difficult to repair, must be replaced. Measuring accuracy are greatly influenced by environmental temperature, temperature package installation location, accuracy is relatively low; Capillary transmission distance is limited, ability is limited. Above is the introduction of the principles and characteristics of the pressure type thermometer, should have further knowledge of it now?