This Korean Industrial Standard specifies the single suction centrifugal or mixed flow submersible motor-pumps for deep well with a bore(2) of 25 to 200 mm, (hereinafter referred to as "pumps"), which handle clean water(1) at ordinary temperature, which are suspended from the lower parts of lifting pipes attached to well covers or fixing bands, and to the lower parts of which are directly coupled with 60Hz, 2-pole 3-phase induction motors by means of shaft couplings.
Notes (') The clean water at ordinary temperature means water at 10°C to 25°C which is
6.5 to 8.0 in pH, 200 ppm or under in chlorine, and 50 ppm or under in sand
content, if any, of which size shall be not coarser than fine sand (0.1 mm to 0.25).
(2) The bore of pump is expressed by the nominal diameter of the discharge
opening of the valve casing of pump body.
Reference As a large amount of sand content sometimes causes failures in motor due to the wear on the sliding parts of the pump, the amount of sand content should preferably be as smaller as poossible.
Remark The units and numerical values given in { } in this standard are in accordance with the conventional system of units, and are appended for reference.