The water inlet of the bite type pipe joint uses a stainless steel piston type water stop ring to seal and stop the water, and the input and withdrawal of the water stop ring are controlled by oil pressure or water pressure. The movement direction of the water stop ring is controlled by changing the direction of the oil (or water) to meet the needs of operation. The seal between the water stop ring and the valve body and the end cover adopts a double O-ring, and the wear of the O-ring can be reduced by setting a PTFE retaining ring.
Each card sleeve joint is equipped with two water stop rings, the upstream side is the inspection seal, and the downstream side is the working seal. The inspection seal is equipped with a manual locking device. The inspection seal is in the normally open state during normal operation and is only used during the maintenance of the unit. To ensure the safety of downstream maintenance, the lock should be manually turned on. The working seal is put in when the ferrule joint is closed, and exits before the ball moves. In order to ensure that the ferrule joint can be quickly closed in an emergency, after the ferrule-type pipe joint is fully opened, the working seal is still in the withdrawal state.
The valve is mainly composed of valve body, sealing ring, O-ring, screw and bit pin. The sealing ring is fixed on the corresponding part of the valve body by a set of screws. The seal between the sealing ring and the valve body is ensured by an O-ring. The function of the positioning pin is to accurately position the sealing ring and the valve body, so as to avoid assembly misalignment with the valve body after the sealing ring is replaced. The material of the sealing ring is usually 2Cr13.
Since the water inlet ferrule joints of water-stop turbines are usually used in power stations with poor water quality and high water heads, the wear of the ferrule joints under severe working conditions is very serious, especially the wear on the sealing surface. In order to improve the maintainability of the bite type pipe joint, the water inlet bite sleeve joint of the bite sleeve joint designs the sealing ring of the bite sleeve joint as a detachable and replaceable structure. After the bite sleeve joint is used for a long time, the valve sealing ring can be seriously worn. Only the sealing ring is replaced without the need to replace the valve or purchase a card sleeve joint separately, which improves the service life of the card sleeve joint body and reduces capital investment.