Structural form of bellows compensator and elastic characteristics of bellows expansion joint

Structural form of bellows compensator:

1. Select the structural form of both ends of the bellows

When selecting the structural form of both ends of the bellows, the forming process, welding process and the structural constraints of the whole system should be considered.

2. Consider whether a guide device is required

When the effective length of bellows is relatively long, in order to avoid column instability in the working process, it should be considered to increase the guide device. For example, bellows for valves are generally equipped with guiding devices.

3. Consider the need for stiffening rings

In order to meet the use requirements of high working pressure, the bellows can be strengthened with reinforcing ring, or multi-layer structure, or the combination of the two structures can be applied. The reinforcing ring is locally strengthened, and the multi-layer structure is integrally strengthened.

4. Select ripple shape

According to the use, performance, application requirements, performance and manufacturing characteristics of various waveforms, a more reasonable corrugated shape is selected. In general, most choose U-shaped bellows, etc.

5. Determine the number of layers of bellows

The number of layers of bellows shall be determined according to the use of bellows, working pressure, stiffness, working medium and other factors. According to the analysis of different calculation formulas, under the condition of equal total wall thickness, the stiffness of multi-layer bellows is only 1 / Z or 1 / Z of that of single-layer bellows. Therefore, multi-layer bellows has many advantages, such as small deformation stress, long service life and so on. Under the condition of high working pressure, corrugated pipes with multi-layer structure are generally selected. For dry multi-layer corrugated pipes, the number of layers and single layer thickness need to be reasonably selected.