The principle of operation of this type of seal is throttling the pressure in the cylinder slots. Slotted labyrinth seals can be used under virtually all operating pressures, peripheral speed and temperature of the pumped liquid. IT’S ensured by performing seals in the form of a set of elementary wear rings, separated by a water seal and discharge chambers, maintaining such pressure differentials and temperatures in the sealing elements, in which the predetermined value leakage and long life seals (25 000 hours or more).
Despite the fact that the work of these seals is accompanied by relatively large energy losses (leakage reaches 4-5% and sometimes 10% of feed), they are widely used in Grundfos 15-29 pumps. Radial clearance in the slot seals in pumps ES usually assumed to be 0,3-0,35 mm. With this value gap seals are susceptible to falling into the throttle gap solids, so the carts in the water seal seals filter is installed (usually double) with a mesh grid 0,1-0,2 mm.
