Precision bellowsThe steel plate has passed ultrasonic inspection, there are delamination defects, so there are good quality and performance problems. In production, production and inspection should be carried out according to specific quality requirements to avoid quality problems in production and use. However, some pipe joints are welded and do not require flanges. The bellows forming process is a process of forming an iron-zinc alloy between the iron substrate and the outer pure zinc layer. During the hot-dip plating process, an iron-zinc alloy layer is formed on the surface of the workpiece, which makes the iron and pure zinc layers well combined.

When the precision bellows is immersed in molten zinc, the zinc and alpha iron (body core) solids melt. This is a crystal formed by dissolving zinc atoms in a corrugated tube in a solid state. The attraction between two metal atoms is small. The allowable displacement of the bellows may be within the effective length of the bellows. Choose between 10% and 40%. When the bellows is subjected to lateral concentrated force, torsional moment or combined force, the allowable displacement of the bellows should be appropriately reduced.

When operating under the same conditions and different working pressure characteristics (constant or alternating load), precision bellows will have different service life. Obviously, the life of the bellows under alternating load is shorter than that under constant load. The bellows is made of environmentally friendly materials, it is corrosion-resistant and recyclable. The pipeline will not break in the environment of -60 ℃, and the high temperature of the transmission medium is 60 ℃.

Without exposure to ultraviolet rays and direct sunlight, its lifespan can even reach more than 60 years. At a certain length, the bellows can be slightly bent without being affected by the bending of the ground. The factors of uneven land subsidence can be ignored directly. When zinc is saturated in the solid melt, the atoms of zinc and iron interdiffuse, and the zinc atoms that diffuse into (or penetrate into) the iron matrix migrate in the matrix lattice. The iron diffused into the molten zinc forms an intermetallic compound FeZn13 with zinc. And sink into the bottom of the flange hot-dip galvanizing pot, called zinc slag. When the bellows is removed from the zinc immersion solution, a pure zinc layer is formed on the surface, which is a hexagonal crystal. Its iron content does not exceed 0.003 percent.

Precision bellowsIt is mainly stable and corrosive. The stability of the bellows can be solved by reasonable design, correct installation and perfect stress analysis of the bellows. Corrosion can be resolved in two ways:

Reasonable bellows material selection and compensator structure design can block the source of corrosion.

2, strengthen the management of indoor water, fundamentally solve the problem of corrosion.

3. In addition to considering the working medium, working temperature and external environment, the material selection of corrugated pipe for heating pipe network should also consider the possibility of stress corrosion, the influence of water treatment agent and pipe cleaning agent on the material. On this basis, combined with the welding and forming of bellows material and the cost performance of the material, the economical and practical bellows material is selected.

In general, the material of precision bellows should meet the following conditions:

1. Through the subsequent treatment process (cold work hardening, heat treatment, etc.), good plasticity can be obtained, which is convenient for the processing and forming of the bellows, and sufficient hardness and strength.

2. High elastic limit, tensile strength and fatigue strength to ensure the normal operation of the bellows.

3, good welding performance, to meet the bellows in the manufacturing process of the welding process requirements.

Good corrosion resistance, to meet the requirements of the bellows in different environments.