The design of the corrugated pipe produced by the Krah machine

The theoretical basis of the Krah machine metal bellows design is plate and shell theory, material mechanics, computational mathematics, etc. The Krah machine bellows design has many parameters. Due to the different uses of the Krah machine bellows in the system, the focus of the design calculation is different.

Here is the content list:

l Outline of the design

l Stress resistant

l Stability

Outline of the design

The Krah machine bellows are used for force balance components, requiring the Krah machine bellows to have the same effective area or small changes within the working range. For measuring components, the Krah machine bellows are required to have linear elastic characteristics; the Krah machine bellows are used as vacuum seals for vacuum switch tubes, which require the Krah machine bellows’ vacuum tightness, axial displacement, and fatigue life; for the Krah machine bellows valves as seals, the Krah machine bellows are required It has certain pressure resistance, corrosion resistance, temperature resistance, working displacement and fatigue life. According to the structural characteristics of the corrugated pipe, the Krah machine corrugated pipe can be composed of a toroidal shell, a flat cone shell, or a toroidal plate. The design and calculation of the Krah machine bellows is also the design and calculation of round shells, flat cone shells, or ring plates.

The parameters calculated by the Krah machine bellows are stiffness, stress, effective area, instability, allowable displacement, pressure resistance, and service life.

Stress resistant

Pressure resistance is an important parameter of the Krah machine bellows performance. The maximum static pressure that the Krah machine bellows can withstand without plastic deformation on the waveform at room temperature is the maximum pressure resistance of the bellows. Under normal circumstances, the bellows are under a certain pressure (internal pressure or external pressure) It works under the pressure, so it must withstand this pressure during the entire working process without plastic deformation.

The pressure resistance of the Krah machine bellows belongs to the strength category of the Krah machine bellows. The key to the calculation is stress analysis, which is to analyze the stress on the wall of the Krah machine bellows. As long as the stress at the maximum stress point on the Krah machine bellows wall does not exceed the yield strength of the material, the pressure on the Krah machine bellows will not reach its pressure resistance.

The same Krah machine bellows under the same other working conditions, the stability of the external pressure is better than the internal pressure, so the maximum pressure resistance, when subjected to the external pressure, is higher than that of the internal pressure.

When the two ends of the Krah machine bellows are fixed, if enough pressure is introduced into the cavity, the Krah machine bellows may be damaged by blasting. When the Krah machine bellows begin to burst, the pressure inside the bellows is called the burst pressure. The burst pressure is a parameter that characterizes the maximum compressive strength of the Krah machine bellows. During the whole working process of the Krah machine bellows, its working pressure is much lower than the burst pressure, otherwise, the Krah machine bellows will be broken and damaged.

Stability

When both ends of the Krah machine bellows are restricted, if the pressure inside the Krah machine bellows increases to a certain critical value, the Krah machine bellows will be unstable.

Eagle Machinery Co., Ltd's carat gold bellows design is based on plate and shell theory, material mechanics, computational mathematics, etc. A wealth of knowledge and experience reserves are the basis for us to do a good job in product quality.