WSS bimetallic thermometer product principle, classification and option guidelines

Bimetallic thermometer works: is to use two different temperature expansion coefficient of metal, in order to improve the temperature measuring sensitivity, is usually made of metal spiral coil shape, when multi-layer metal temperature change, the layers of metal expansion or contraction, makes the spiral coil rolled up or let go. As a result of the spiral coil end fixed and the other end connected to a free rotating pointer, therefore, when the bimetallic strip feel the temperature change, Pointers can be on a circular dividing scale to indicate the temperature. This kind of instrument of temperature measurement range is - 80℃- + 500 ℃, the permissible error is about 1% of the scale range. Classification: according to the bimetallic thermometer pointer plate with the direction of protecting tube connection bimetallic thermometer can be divided into axial, radial and 135 ° to the model and universal model. (1) the axial type bimetallic thermometer: pointer vertical connection tube plate and protection. (2) the radial type bimetallic thermometer: pointer GuanPing line connection plate and protection. (3) type 135 ° to the bimetallic thermometer: pointer plate connected to protection tube into 135 °. (4) universal type bimetallic thermometer: pointer plate connected to the protecting tube Angle can be arbitrary adjustment. Installation fixed form: in order to adapt to the needs of practical production, bimetallic thermometer has different installation fixed form: movable external thread pipe joint, movable threaded pipe joints, fixed nipple, card sets of nipple, flange joint and a fixed flange. Model name: W S S - - - — No - form of protection W - type of permanent way Protection type 0 No fixed device F - 1 - to anti-corrosion type structure Movable external thread 0 2 - axial type Movable internal thread 1 - 3 - radial type Fixed screw 2 - 4-135 ° to type Fixed thread 3 - 5 - universal type 6 - card set of threaded casing of nominal diameter 3 - card flange φ60 4 - φ100 5 - Phi 125 thermal element is double metal metal expansion type temperature instrument selection guidelines: when choosing 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 of insertion of the measured medium length should be not less than two-thirds of the length of the sheath maerial, banned twist instrument shell during installation.