Bellow

 Bellows is a tubular elastic sensitive element made of foldable wrinkled sheets connected in the direction of folding and expansion. Bellows are widely used in instrumentation, the main use is as a pressure measuring instrument measuring element, the pressure is converted into displacement or force. The bellows has a thin wall and high sensitivity, with a measuring range of tens of Pa to tens of MPa. It has a fixed open end and a free sealing end, and uses an auxiliary coil spring or reed to increase elasticity. When working under the action of internal pressure along the length of the tube elongation, so that the active end of the pressure into a relationship with the displacement. The active end drives a pointer that directly indicates the size of the pressure. Bellows are often combined with displacement sensors to form a pressure sensor with an electrical output, and are sometimes used as an isolation element. Because bellows stretch requires a large volume change, its response speed is lower than that of bourdon tube. Bellows are suitable for measuring low pressure.

Bellows Mainly include metal bellows, corrugated expansion joints, corrugated heat exchanger tubes, diaphragm diaphragm boxes and metal hoses. Metal bellows is mainly used to compensate for pipeline thermal deformation, shock absorption, absorption of pipeline settlement deformation, etc. It is widely used in petrochemical, instrumentation, aerospace, chemical, electric power, cement, metallurgy and other industries. Plastic and other materials such as bellows in the medium of transport, electric power threading, machine tools, home appliances, etc. has the role.

   Bellows: a pressure measuring instrument in the pressure measurement elastic element. It is a cylindrical thin-walled folded shell with multiple transverse corrugations, bellows has the elasticity, in the pressure, axial force, lateral force or bending moment can produce displacement. Bellows are widely used in instrumentation, the main use is as a pressure measuring instrument measurement element, the pressure is converted into displacement or force. Bellows have a thin wall, high sensitivity, and a measurement range of tens of Pa to tens of MPa. In addition, bellows can also be used as a sealing and isolation element to separate two media or to prevent fluids from entering the measuring part of the device. It can also be used as a compensating element to compensate for temperature errors in the instrument by taking advantage of the variability of its volume. Sometimes also used as two parts of the elastic coupling joint. Bellows according to the composition of the material can be divided into metal bellows, non-metallic bellows two; according to the structure can be divided into single-layer and multi-layer. Single-layer bellows is used more. Multi-layer bellows, good sex, small stress, used in important measurements. Bellows material is generally bronze, brass, stainless steel, monel alloy and inconel alloy.