To achieve the purpose of the invention, there is provided a diaphragm valve comprising: an actuator; and a valve part including: an inlet passage; an outlet passage which is brought into communication with the inlet passage when the diaphragm valve is opened; a valve chamber provided with a valve seat and placed between the inlet passage and the outlet passage; a suck-back chamber placed between the inlet passage and the outlet passage and in vertically aligned relation with the valve chamber;Cast Steel Valves a through hole through which the valve chamber and the suck-back chamber are brought into communication with each other when the diaphragm valve is opened; a first diaphragm which integrally includes a valve element and forms a part of the valve chamber and is mounted to have an outward curve with respect to the valve chamber, the first diaphragm being deformable so that the valve element is brought into and out of contact with the valve seat by operation of the actuator; a seconddiaphragm which forms a part of the suck-back chamber and is mounted to have an outward curve with respect to the suck-back chamber, the second diaphragm being substantially identical in shape to the first diaphragm; and a connecting rod which is movably placed through the through hole and connects the first and second diaphragms so that the first and second diaphragms are synchronously deformed by operation of the actuator.

According to another aspect, the present invention provides a diaphragm valve comprising: an actuator; and a valve body formed with: an inlet passage; an outlet passage which is brought into communication with the outlet passage when the diaphragm valve is opened; a valve chamber which has an open upper end and is provided with a valve seat, the valve chamber being placed between the inlet passage and the outlet passage;Forged Steel Valves a suck-back chamber which has an open lower end and is placed between the inlet passage and the outlet passage; a through hole through which the valve chamber and the suck-back chamber are brought into communication with each other when the diaphragm valve is opened, a surrounding portion of the through hole forming the valve seat; a first diaphragm which integrally includes a valve element and an circumferential edge portion and is placed to close the open end of the valve chamber, the first diaphragm being deformable so that the valve element is brought into and out of contact with the valve seat;WATER POWER CONTROL VALVE a second diaphragm which is provided with an circumferential edge portion and is placed to close the open end of the suck-back chamber; a first retaining member which retains the circumferential edge portion of the first diaphragm against the valve body to fix the first diaphragm in place; a second retaining member which retains the circumferential edge portion of the second diaphragm against the valve body to fix the second diaphragm in place; and a connecting rod which is placed through the through hole and connects the first and second diaphragms so that the first and second diaphragms are synchronously deformed by operation of the actuator.

MORE NEWS