Welded bellows

Metal bellows are widely used in industrial environment, in vacuum technology, in centrifugal pumps nodes and in electrical equipment. They divide into two main groups. The first group consists of seamless bellows (hydro formed or unrolled). The second group consists of membrane type welded bellows. Bellows luminous welded represent a circular membrane with wavy profile interconnected by welding alternately on the outer and inner diameters. Thus far, they are the most sophisticated and have a number of significant advantages over the extruded bellows:

a) A large axial displacement in conjunction with compact axial dimensions;

b) High cycle life;

c) Possible high-speed movement;

g) Small axial stiffness combined with its small scatter;

d) High-level operating pressure.

Membrane profile design is optimized to reduce the stresses in the weld-affected zone of the internal weld and for tapping them into less loaded peripheral zone. This leads to a higher life at higher loads - up to 1 million of compression-tension cycles, as well as the higher axial resistance of the bellow (especially under the load by the external overpressure). In addition, the production of multilayer bellows makes possible to use these products in different environmental conditions with a maximum permissible working pressure up to 20 MPa.

Strict control ensures high quality of the product. Visual inspection of welds is carried out after each operation as well as the product general leak is assessed through non-destructive testing and helium mass spectrometry leak detection. All products are subject to the necessary vacuum heat treatment followed by tightness control depending on the material design.

RUS

ENG