Metal hoses are often used for compensation, vibration isolation and noise reduction in practical projects to achieve good results. Just because they have the above functions, they are more and more widely used in projects. However, there have been some problems in the application. The root cause of these problems is mainly due to improper selection or installation.
The so-called model selection means that the diameter, connection type, working pressure, temperature correction, minimum bending radius, and length of the metal hose must be selected appropriately, otherwise it may cause early failure of the metal hose and cause major personal and equipment accidents. The pressure specified in the model is the design pressure Ps of the product, which cannot be less than the working pressure PN, but should not be too high. Generally, Ps ≥ K (t) PN is enough, otherwise, although the pressure bearing capacity of the hose is improved, the bending life will be greatly reduced.
According to the previous fault analysis, most of them are caused by fatigue, while those due to insufficient pressure bearing capacity are rare.
The load conditions and installation of metal hoses in use are also matters that must be noted. The minimum bending radius Rs of metal hoses is a particularly critical parameter in engineering applications, which will directly affect the service life of hoses. The working conditions in practical application are various, and the service conditions are also very complex. Therefore, it is very difficult to obtain an accurate design bending radius with strong universality by theoretical calculation method.
It can be selected by users when ordering. For general working conditions, such as:
For no vibration and no repeated bending, Rs=Rj (static bending radius) can be selected;
In case of no vibration and repeated bending, Rs=Rd (dynamic bending radius) can be selected;
For vibration and repeated bending, Rs=fRd (f=1.5-2, safety factor) can be selected;
For some special purposes (such as top blowing oxygen hose for converter), special analysis and calculation are required.
