How to use welded/formed bellows 1
Even identical bellows are different in guaranteed life according to the usage method and conditions.
Please check the content that requires consideration and caution in use.
Points to use bellows
Points
When using bellows not only the performance of the bellows is important but the bellows assembly fully demonstrates the performance. In the following cases, special consideration is required. Our design skills have been improved over many years. Please feel free to ask us.
- Selection of bellows materials
What is generally considered to be used in bellows are corrosion resistance and the presence or absence of magnetism.
If there are no special requests regarding the above two points, please leave it to our discretion. We will make considerations based on low-cost materials with a short face-to-face dimension.
- Interference with shafts,etc.
It is necessary to select bellows whose inner/outer dimensions of the bellows and the clearance of the shaft, etc., are 2mm or more on one side.
This is to avoid a reduction in lifetime through contact by meandering or horizontal deflection of the bellows. In a multiblock construction, there are cases where the inner-diameter shafts provide support to prevent buckling, with the result that the one-side clearance may become larger than 2mm.
- Meandering and buckling
If bellows become long, there are cases where they have a multiblock construction in order to prevent meandering and buckling by spring properties.
When meandering and buckling are prevented by providing shafts on the inner-diameter side, there is a need to secure a large clearance to the inner diameter of the bellows in consideration of the sliding portion.
- Dust generation
Early damage may occur from foreign matter caught in the equipment. Caution is required because it can significantly affect the horizontal posture.
For using bellows at low cost
It is possible for us to design your bellows in consideration of your usage environment.
However, in some cases, a design can be made at a lower cost with a shorter face-to-face dimension than specifications if the following are considered in your equipment design.
- The internal (external) pressure of the bellows is kept constant and unchanged. There are no pressure fluctuations.
- For obtaining axial displacement, displacement perpendicular to the axis and angular displacement are eliminated.
- The operating speed is set in a range not exceeding 100mm/sec.
- Fittings and bellows are welded by us.
- Designs are performed with our own sizes.