(1) Submersible sewage pumps of various series, including AS, AV, QW (WQ), and JYWQ, as well as foreign brands, are available in both mobile and fixed installation types. Selection should be based on the national building standard design atlas 01S305, "Selection and Installation of Small Submersible Sewage Pumps". Mobile installation with hose connection is limited to submersible sewage pumps with a motor power N ≤ 7.5kW and a discharge pipe diameter DN ≤ 100mm.
(2) Submersible sewage pumps are automatically controlled using a liquid level automatic control device. Besides float-type liquid level switches, if the sewage contains no or only a small amount of suspended impurities, an immersion pressure sensor and matching secondary instruments can also be used. The liquid level automatic control device installed in the sewage tank (collection well) should be as far away from the inlet as possible.
(3) For indoor sewage tanks (collection wells) with a single submersible sewage pump weighing more than 80kg, a hook should be pre-embedded in the floor slab or beam above the inspection hole for lifting the submersible sewage pump during installation and maintenance.
(4) According to the current relevant specifications, except for the use of fabric-reinforced rubber hoses for the connection parts of mobile installation hoses, the discharge pipe of the submersible sewage pump can be made of rigid water supply plastic pipes, centrifugally cast ductile iron water supply pipes, steel pipes, steel-plastic composite pipes, etc. The pressure-bearing capacity of the pipes and fittings should not be less than 0.6 MPa.
(5) For the installation of submersible sewage pumps used in the sump pits of building fire elevators, two rigid pipes connected in a fixed manner or two fixed self-coupling pumps should be used, and the effective volume of the sump pit should not be less than 2.0 m3, and the rated flow rate of the submersible sewage pump should not be less than 36 m3/h.
(6) Control valves, check valves, flexible rubber hose joints, and pressure gauges should be installed on the discharge pipe of the submersible sewage pump. The National Building Standard Design Atlas 01S305 "Selection and Installation of Small Submersible Sewage Pumps" recommends using gate valves for control valves, but butterfly valves can also be used as needed; spherical sewage check valves are recommended for check valves. Submersible sewage pumps are units assembled from a submersible motor and a submersible pump, or a single unit where the pump components are directly mounted on the motor shaft extension. These pumps operate submerged in well water, rivers, lakes, oceans, and other underwater environments. They offer advantages such as small size, light weight, no need for priming, no suction head limitation, no need for a separate pump house, easy installation and use, reliable performance, high efficiency, low price, and cost savings. Main applications of submersible sewage pumps: They are widely used for drawing water from wells, rivers, and lakes, agricultural irrigation and drainage, and urban water supply.
