The ABV-S series was developed for loading processes where the traditional load-limited breakaway couplings (see ABV and ABVL series) cannot be used. This particularly applies to applications where tensile forces must not at all or may only be marginally applied on the loading line.
ABV-S series breakaway couplings separate the line when the mobile unit exceeds a pre-set radius of motion. The radius of motion should be smaller than the maximum deflection of the loading line. Both coupling halves are equipped with a non-return valve each that allows to close the line impermeably when it is separated and to exclude that the medium escapes into the environment.
The basic principle:
Compared with load-limited triggering (see ABV and ABVL series), the ABV-S series triggers without any stress on the loading line via a load cable that limits the radius of motion of the mobile unit. The trigger mechanism actuated via the cable is patented and has set the standard in this product segment for years!
The ABV-S series couplings consist of two coupling halves. These are connected via a pair of flanges by means of a patented clamp/supporting ring system during normal operation. The supporting ring is connected to a rope that has to be attached to the stationary unit in a way that it is always shorter than the loading line independent of the direction of motion of the mobile loading partner.
When exceeding the radius of motion thus defined, the cable tightens, pulls the supporting ring from the clamp/supporting ring system thus loosening the connection between the two coupling halves. In this case, the separated coupling halves must be closed immediately; for this purpose the two housing halves are equipped with spring-loaded non-return valves. In the operating state, they brace each other and keep the flow cross-section open. In the case of separation the mutual support effect of the valves no longer exists so that they abruptly close each cross section being released.
For example, at a loading station equipped with a hose loading arm, the "release cord" is attached at a suitable point by means of a load cable anchor. In case of emergency, the coupling immediately separates the line – without causing damage to the hose, coupling, vehicle or loading plants. At both sectioning points, the valves in the safety couplings abruptly close so that no medium can escape.