Valves that are generally placed in the upper part of silos or hoppers may be put under pressure or vacuum unexpectedly, which can cause serious structural damage; for example, due to bulging, positive pressure, inward deformation or folding due to vacuum. It may even lead to catastrophic damage.

UK valves are very simple. They work with counterweights without any type of actuation, with the corresponding flap opening when necessary. GORCO has a range of various models according to the necessary capacities.