Hyquip flap valves are offered in three different versions: gravity, motorized and pneumatic to suit different applications in the industry. They are preferred for handling highly abrasive or lumpy materials which have tendency to stick. They can also be installed in tandem for very high differential pressures. No rotary action means no need to build clearance (leakage) into the valve. Double flaps ensure that the seal is never lost throughout filling and emptying of the valve. Full-throat opening eliminates bridging, jamming and material build up. Seat and flapper can be reground several times to bring them back to original condition and performance. Housing does not come in contact with material which allows much longer life.