The drainage pumps used in the building include submersible sewage pump, underwater drainage pump, vertical sewage pump and horizontal sewage pump. As the general site in the building is small and the displacement is not large, the submersible sewage pump and submerged drainage pump can be preferred for the drainage pump, among which the submerged sewage pump is generally used in important places; the vertical sewage pump and horizontal sewage pump are required to be equipped with isolation foundation, self irrigation water absorption, and occupy a certain space, so they are rarely used in buildings.

The flow rate of the drainage pump should be selected according to the design second flow rate of domestic drainage; when there is displacement adjustment, it can be selected according to the maximum hourly flow of domestic drainage. The flow rate of drainage pump in fire elevator sump shall not be less than 10L / s. After the head of the drainage pump is determined according to the lifting height and pipeline loss, a certain free head is added. The free head should be 0.02-0.03mpa. The velocity of suction pipe and outlet pipe of drainage pump should not be less than 0.7m/s and should not be greater than 2.0m/s. A standby pump should be set in each domestic drainage sump in public buildings, which should be operated interactively at ordinary times. If there are two or more drainage pumps for the basement, equipment room and garage, the pump can not be used. When the emergency drainage pipe cannot be set in the sump, the pump shall have uninterrupted power supply; when the drainage inlet pipe can be closed, the uninterrupted power supply can not be set, but alarm device shall be set.

When lifting the sewage and wastewater with large impurities, the outlet pipes of submersible sewage pumps in different catchments should not be discharged together; when lifting general wastewater, the outlet pipes of submersible sewage pumps in different catchments can be combined and discharged according to the actual situation. When two or more pumps share one outlet pipe, valves and check valves shall be installed on the outlet pipe of each pump. Check valve should be set when single pump drainage may cause backflow. It is not allowed to discharge the pressure drain and gravity drain pipe in the building. When the submersible sewage pump lifting contains large debris, the submersible sewage pump should be equipped with crushing device; when lifting sewage containing more fiber, large channel submersible sewage pump should be used.

When the motor power of submersible sewage pump is greater than or equal to 7.5kW or the outlet diameter is greater than or equal to DN 100, the fixed auto coupling device of the pump can be used; when the motor power of the submersible sewage pump is less than 7.5kW or the diameter of the outlet is less than DN 100, the mobile installation of the hose can be set. When the submersible sewage pump is used to drain the sewage sump, the pump fixed auto coupling device should be set to facilitate the maintenance of the pump. The drainage pump shall be able to start and stop automatically and manually on site. Multiple pumps can be operated alternately in parallel or in sections.

Technology Department