Abstract: Disclosed is a manual balancing valve having an upstream end and a downstream end, and a first equalizing ring (500a) and a second equalizing ring (500b) configured at the upstream end and the downstream end, respectively. Each of the first and the second equalizing rings comprises an annular body (505) defined between an inner peripheral edge portion (510) and an outer peripheral edge portion (515), an annular chamber (520) configured adjacent to the inner peripheral edge portion, a plurality of holes (525) configured on the inner peripheral edge portion and in fluid communication with the annular chamber, and a pressure tap (T) in fluid communication with the annular chamber and extending radially outward of the annular body. The first and the second equalizing rings are adapted to provide static pressure value at each of the upstream and the downstream ends so as to measure differential pressure therebetween and control the fluid flow rate through the valve.

Abstract: Disclosed is a manual balancing valve having an upstream end and a downstream end, and a first equalizing ring (500a) and a second equalizing ring (500b) configured at the upstream end and the downstream end, respectively. Each of the first and the second equalizing rings comprises an annular body (505) defined between an inner peripheral edge portion (510) and an outer peripheral edge portion (515), an annular chamber (520) configured adjacent to the inner peripheral edge portion, a plurality of holes (525) configured on the inner peripheral edge portion and in fluid communication with the annular chamber, and a pressure tap (T) in fluid communication with the annular chamber and extending radially outward of the annular body. The first and the second equalizing rings are adapted to provide static pressure value at each of the upstream and the downstream ends so as to measure differential pressure therebetween and control the fluid flow rate through the valve.

Abstract: A metal plate for a dual plate check valve includes a substantially circular segment shaped plate member of a predetermined substantially uniform thickness and is pivotally mounted to enable rotation about an axis substantially parallel and adjacent to a chord. The plate member has a central portion and two extreme end portions distal to the central portion. The end portions are provided with reinforcements thereby increasing the thickness of the plate member in the end portions, the reinforcements being located so that when the plate member of the check valve is in a closed position, the end portions with reinforcements are in a radially outward direction from the valve seat of the check valve. When back pressure acts on the plate member, the reinforcements enable the plate member to distort substantially uniformly to maintain sealing contact with the valve seat.