Rattay stainless steel metal hoses are resilient parts that are also suitable for rough conditions. Nevertheless, there are some basic points that need to be observed during installation to ensure a long service life.
- External loads on the hose caused by scraping on edges, surfaces or the ground, because bending or a reduction of the wall thickness can seriously reduce the service life.
- The minimum bending radii stated in the hose tables may not be exceeded.
- Torsion-related tension must be avoided. Therefore steps should be taken to ensure that the hoses are not twisted when installed (counteracting wrench - pliers).
- Steps should also be taken in terms of movement during operation so that no torque occurs. Therefore, both ends of the hose connections must lie on the same level. The following shows some typical installation errors and how to avoid them.
When rolled up, damaging torsion loads on the metal hoses can occur when the ends are pulled and the smallest allowed bending radius is undercut. Correct rolling up and unrolling helps avoid this error.
If the length of the hose is too short, the metal hose will be bent at the connection points. A straight piece of 3 – 5 x DN must be added to the length calculated from the bending radius per connection side. Selecting a larger bending radius than the smallest allowed radius significantly increases the service life.
Incorrect installation of the metal hoses leads to heavy bending loads behind the connections. The attachment of a pipe elbow helps eliminate this error. Placement on a saddle or a roll with an adequate diameter prevents excessive bending.
Placement on a saddle or a roll with an adequate diameter prevents excessive bending.
When the braid lifts from the metal hose the pressure resistance is no longer guaranteed. Axially installed metal hoses with braid are therefore not allowed as expansion compensators.
Here again, this source of error can be avoided by attaching pipe elbows.
Torsion movements lead to premature destruction of the metal hoses and usually occur through wrong installation.
Ensure that the pipe axes run in parallel or the hose axes and movement direction are on the same level.
Poor attachment, as shown on the left, should be avoided if possible. If this is not possible, a support or roller with a counter weight should be attached to prevent the hose sagging.