The Davies classic SPK series differ from conventional self-priming pumps as they have no check valve or any other type of valve built in, nor is there any recirculation of water during the pumping cycle once the pump is primed. This unique design gives positive pumping, low cost and maintenance, with high efficiency.
No check valve or foot valve is required on the suction hose, but a suitable strainer to prevent large debris entering the pump is necessary. If it is desirable to keep the suction and discharge pipes full, a foot valve or check valve may be used.
Once the pump is initially primed, sufficient liquid is always retained to permit the pump to self-prime though the suction and discharge lines drain back to the liquid source.
The pump will self-prime without ever vapour locking due to the ability to self-purge gases. This feature allows the pump to operate on snore” (pumping air and water) continuously without affecting the pump.
Should cleaning be necessary the removal of one set screw and cover plate on the front pump allows access to the centre of the impeller and the lower casing.
A semi open impeller and a replaceable nylon wear plate is standard in all Davies SP Pumps, allowing solids in suspension to be pumped without blockages occurring provide a suitable suction strainer is used.