Release time:

2023-08-14

Points for attention to the suction pipe and outlet pipe of the sewage self-priming pump: (1) The suction pipe of the sewage pump Each sewage pump should be set up with a separate suction pipe, and strive to be short to improve water conservancy conditions, reduce head loss, and reduce the possibility of impurities blocking the pipeline. The design flow rate of the suction pipe is generally 1.0~1.5 m/s, and the low rate shall not be less than 0.7 m/s to avoid precipitation in the pipe. When the suction pipe is very short, the flow rate can be increased to 2.0~2.5 m/s. In order to facilitate the removal of air stored in the suction pipe, the horizontal part of the suction pipe should be slightly raised along the direction of the water flow, and the pipe slope can be 0.005. When the connection between the suction pipe and the water pump needs to be tapered, the eccentric reducer shall be adopted. The entrance of the suction pipe should be equipped with a bell mouth, the diameter of which is 1.3 to 1.5 times the diameter of the suction pipe. The bell mouth is installed in the water accumulation pit of the water collection tank. For self-filling water pumps, valves shall be installed on their suction pipes for maintenance. If the pump is not self-filling, the vacuum pump or water ejector should be used to start the pump, and the bottom valve is not allowed to be set on the suction pipe, because the bottom valve is easy to be blocked in the sewage, which affects the starting of the pump and increases the head loss and power consumption. (2) The flow rate of the outlet pipe of the sewage pump is generally not less than 1.5 m/s. When two or more pumps share one outlet pipe and only one pump works, the flow rate shall not be less than 0.7 m/s to avoid deposition in the pipe. When the outlet pipe of the pump is connected to the outlet main pipe (connecting pipe), it shall not be connected from the bottom of the main pipe, so as to avoid siltation in the outlet pipe of the pump when the pump stops running. When two or more water pumps share a water outlet pipe, the water outlet pipe of each water pump shall be equipped with a valve, and a check valve shall be set between the valve and the water pump; if the water pump adopts a separate water outlet pipe and is free flow, generally no check valve may be set, and all valves shall be installed in the horizontal section as far as possible to avoid dirt settling on the valve plate. The pipeline laying in the sewage pumping station generally adopts surface installation. The suction pipe is permanently placed on the ground, and the outlet pipe is mostly installed overhead due to the deep pump room, usually on the bracket along the wall. The layout of the pipeline shall not hinder the transportation and maintenance work in the pumping station. It is not allowed to install the pipeline over the electrical equipment. It shall not hinder the transportation, equipment hoisting and maintenance in the station. Attention points for the suction pipe and outlet pipe of the ground sewage pump at the passage. Attention points for the suction pipe and outlet pipe of the sewage pump should not be less than 2.0m from the bottom of the pipe, and the pipeline should be stable. In order to facilitate the installation and disassembly, the pipeline in the pump station generally adopts flange interface. Corresponding anti-corrosion measures shall be taken for pipelines and valves.