Vacuum Parts bellows

What is bellows?

The bellows in vacuum parts are tubular elastic sensing elements connected by foldable wrinkles in the direction of folding and stretching.

Bellows are widely used in instruments and meters. They are mainly used as measuring elements of pressure measuring instruments to convert pressure into displacement or force. Corrugated tube has thin wall and high sensitivity. The measuring range is from tens of PA to tens of MPa. The opening end is fixed, the sealing end is in a free state, and the auxiliary spiral spring is used or the elasticity is increased. Under the action of internal pressure, the movable end of the pipe extends along the length direction of the pipe, resulting in displacement which has a certain relationship with the pressure. The movable end can drive the pointer to directly indicate the size of the pressure. Bellows are often combined with displacement sensors to form a pressure sensor whose output is electricity, and sometimes used as isolation elements. Because the expansion of bellows requires larger volume changes, the response speed of bellows is lower than that of Bourdon tube. Bellows are suitable for measuring low pressure.

The bellows of vacuum parts mainly include metal bellows, bellows expansion joints, bellows heat exchanger tubes, diaphragm box and metal hoses. Metal bellows are mainly used to compensate the thermal deformation of pipelines, shock absorption, settlement deformation of pipelines and other functions, widely used in petrochemical, instrumentation, aerospace, chemical, power, cement, metallurgy and other industries. Corrugated pipes made of plastics and other materials play an irreplaceable role in the fields of medium transmission, power threading, machine tools and household appliances.

Bellows: a pressure measuring elastic element in a pressure measuring instrument. It is a cylindrical thin-walled corrugated shell with multiple transverse ripples. The corrugated pipe is elastic and can produce displacement under the action of pressure, axial force, transverse force or bending moment. Bellows are widely used in instruments and meters. They are mainly used as measuring elements of pressure measuring instruments to convert pressure into displacement or force. Corrugated tube has thin wall and high sensitivity. The measuring range is from tens of PA to tens of MPa. In addition, the bellows can also be used as sealing and isolating elements, separating the two media or preventing harmful fluids from entering the measuring part of the equipment. It can also be used as a compensation element to compensate for the temperature error of the instrument with the variability of its volume. It is sometimes used as an elastic joint for two parts.

Bellows classification:

Bellows can be divided into metal bellows and non-metal bellows according to their composition materials, and can be divided into single layer and multi-layer according to their structure. Single layer bellows are widely used. Multilayer bellows has high strength, good durability and low stress. It is used in important measurements. The bellows are usually made of bronze, brass, stainless steel, Monel alloy and Inconel alloy.