If the ring O-ring as a result of external factors is exposed to flow through the gap of the structure, should be added security called back-up ring. This takes place in the following cases:

• high dynamic motor loads causing movement of the part of the structure with respect to the seal which as a result of the friction force and the thrust coming from the sealed fluid pressure, affects its pushing into a slot, formed by moving and fixed elements of the structure, consequently jamming.
• the gap size exceeds the recommended value for the hardness of the rubber.
• insufficient stiffness of the structural elements in relation to the acting external loads especially pulse causing their cyclical "swelling" and following the progressive pressing the seal into the slot.

The mechanism of insertion seal into the building gap and a method for the prevention is shown in the following drawings:

Detailed information available in the directory: