All bearings are water-lubricated and have a squared shape enabling sand particles, if any, to leave the pump together with the pump liquid.
The inlet strainer prevents particles over a certain size from entering the pump.
All pumps are equipped with a non-return valve in the valve casing preventing back flow in connection with pump stoppage. Furtheremore, the short closing time of the non-return valve means that the risk of destructive water hammer is reduced to a minimum. The valve casing is designed for a optimum hydraulic properties, to minimize the pressure loss across the valve and thus contributes to the high efficiency of the pump.
The stop ring prevents damage to the pump during transport and in case of up-thrust in connection with start-up. The stop ring, which is designed as a thrust bearing, limits axial movements of the pump shaft.