Volume loss of centrifugal pump including seal ring leakage loss, balancing mechanism leakage loss and interstage leakage loss. This article describes the seal ring leakage loss.
In the entrance of the impeller is a seal ring, when the pump works, because the sealing ring on both sides with pressure difference between the side of the approximately impeller outlet pressure side of the impeller inlet pressure, so there will always be a part of the liquid from the impeller to the outlet impeller inlet leak. This part of the liquid in the impeller in obtaining energy, but the liquid did not sent, thus reducing the water supply pump. All the energy used to overcome the leakage of fluid resistance of the seal ring.
Obviously, if the sealing ring diameter larger ,pressure on both sides is more special, the greater the amount of leakage. For stereotypes pump, in order to improve feed efficiency of the pump leakage amount should be permitted in the case of the sealing ring gap is narrowing. Usually approximated total clearance seal ring diameter of 0.002, as Dw = 200 mm, the total clearance of 0.40 mm, when assembled, the sealing ring can not be eccentric too large, otherwise the amount of leakage also increases. The main measures In addition, the sealing ring can be used to increase the resistance method of reducing the amount of leakage, increase the resistance of the seal ring is made of a maze, zigzag, etc., which also increases the length of the sealing ring seal, increasing the resistance along the way.
Ring seal leakage, and in some cases cause disturbance of the impeller inlet, so will the rational design of the sealing ring form.
