Abstract: Due to various conditions, the domestic sewage, industrial waste water and rainwater can not be completely shunted in Shanghai. The contaminated water body can not be fully purged and the sources of pollution can not be fully controlled. However, sewage pumping station can be used to transport, intercept domestic sewage and industrial waste water. Shanghai's sewage pumping station plays a key role in controlling and improving the city's water pollution. Keywords: sewage pumping station pump I. Introduction Shanghai is a very prosperous large-scale modern city, its development goal is to build an international economic, financial and trade center, which requires the city must have a rich water resources and superiority The water environment and its status to adapt. However, due to various conditions, the domestic sewage, industrial wastewater and rainwater can not be completely diverted from the system in Shanghai. The contaminated water body can not yet be fully purified and the sources of pollution can not be fully controlled. However, sewage pumping station can be used to transport, intercept domestic sewage and industrial waste water. Shanghai's sewage pumping station plays a key role in controlling and improving the city's water pollution. In Shanghai's sewage pumping station (such as Wuchuan pumping station, etc.), the commonly used MF (MN) pump has become increasingly obvious shortcomings, maintenance and installation of low accuracy, noise, daily management and maintenance workload, and even produce toxic and harmful gases, Endangering personal safety, etc .; the same time, due to pump failure and had to stop the transport, intercepting the area of ​​sewage, may not reach the production targets, will directly affect the unit's economic and social benefits. With the advancement of science and technology in the pump industry, a large submersible sewage pump made of new material, new structure and new technology can completely replace the original MF (MN) pump and its development trend is rapid. Such as the current commonly used FLYGT-C (Flygt) pump, which contains a certain scientific and technological means and quality of large submersible sewage pump, by the majority of engineering and technical personnel and pumping station managers generally welcome. Second, the FLYGT-C pump alternative MF (MN) pump is the basic condition of the two pumps in common 1, the two pump flow and lift performance curve, flow and power performance curve, flow and efficiency performance curve is similar. 2, the above two pump pumping medium (water) temperature, caliber, flow, lift, voltage, power, ground control board, etc. are the same. Third, the FLYGT-C pump alternative MF (MN) The superiority of the pump is its unique high-tech 1, FLYGT-C pump in the structural design, process production than the MF (MN) pump more scientific and reasonable MF (MN) A motor shaft, bearing box, pump shaft, coupling and other transmission units, the shaft stainless steel inserts. Mainly by the motor when the fan leaves to cool, long-term operation, the cooling effect is poor. During operation, the motor itself is unprotected and needs to be controlled by a control cabinet on the ground. If the motor stops running for a long time, it is easily affected by the impact of moisture. During operation, the pump is usually sealed with a mechanical seal and a packing. The mechanical seal needs to be primed. Otherwise, the pump may be damaged by a slight mistake. The packing seal is easily softened and softened due to continuous operation all day long and needs to be replaced frequently. Pump and impeller anti-corrosion technology behind, poor corrosion resistance, the surface is very rough. FLYGT-C pump motor shaft and pump shaft share one, the pump shaft is an extension of the motor shaft, made of stainless steel material. Two bearings in the entire submersible pump. The pump is immersed in water to work and it gets enough cooling by the surrounding environment and the pumped medium without the need for an external cooling system. The pump stator coil immersed in Class F insulating paint 3 times and baked 3 times, the stator coil into the thermal switch, and the motor overload protection, oil leakage protection through the sensor connected to the ground control cabinet. Motor cable inlet sealing performance exceptionally strong, it is a cylindrical elastic bushing, outer washer, bushing can be squeezed by the cable into the cable chamber and eliminate the tension and a certain torque, this incoming device to ensure easy replacement Damaged cable, instead of epoxy, silicone or other secondary seal. Pump sealing performance has its own uniqueness, it has two independent upper and lower mechanical seal consisting of a series: lower seal (first seal) is located between the pump housing and the oil chamber, by a stationary ring and a forward rotation Corrosion-resistant tungsten carbide ring; the upper seal (second seal) between the oil chamber and the motor consists of a ceramic stationary ring and a positive rotating carbon ring. The two sealed interfaces are connected by their own spring system. The mechanical seal can be rotated clockwise and counterclockwise without damaging the sealing element without service and adjustment. The exterior of the pump and the metal surface of the pumped medium are sprayed with anticorrosive paint. Between the volute and the impeller suction port wear ring, made of clear rubber coated steel or brass, thus ensuring the volute and impeller suction between the effective seal. 2, FLYGT-C pump installation MF (MN) pump more simple and fast MF (MN) pump in the construction, the need to build a large pump room, the installation of the escalator, lighting, ventilation, submersible pumps, wells and Other auxiliary equipment and facilities. In the installation of the pump must be solid foundation, never allow the pump itself as a support point for the pipeline to withstand the weight of the pipeline. It is worth mentioning that: the pump and drive shaft accurate alignment, if sealed with packing, the two axial and axial coupling shaft deviation of not more than 0.1 mm, due to long-term operation, the foundation (triangular iron shelf) gradually Loose, corrosive, so that the pump installed in the maintenance of a certain degree of difficulty. FLYGT-C pumps are constructed and retrofitted without the auxiliary equipment and facilities in the pumps required for MF (MN) pumps, greatly reducing capital and time for construction, reducing capital and installation time for auxiliary facilities such as FLYGT -C pumps and other large submersible sewage pump can replace MF (MN) pump one of the biggest advantages. The FLYGT-C pump is simple to install. The submersible pump slides freely from the top of the pump pit to the drainage connection seat under the guide of not less than two parallel guide rods, and can automatically connect with the drainage connection seat without the installation worker going down Installation and maintenance. The seal of the pump and drain connection is completely metal-to-metal contact and does not require a drain seal in the form of a membrane, o-ring or gasket. The entire weight of the pump is borne by the pump's drainage curve and the pump-specific lifting chain. The load on the lifting chain is double that of the total weight to ensure stability. 3, FLYGT-C pump in the operation and management than the MF (MN) pump safer and easier MF (MN) pump before the operation, there are strict operating procedures, such as opening the inlet valve, open the Gap, Pump air, disc drive coupling, check the coupling gap. During operation, the pump must be distinguished by its diligence, diligence, diligence and diligence. It is necessary to frequently walk the escalator between high and low pumps, especially if a lesbian is on duty. Potential fear How much will affect the safety of the work and the quality of day-to-day management. Pump in operation, the noise, vibration, seriously hampered the pumping station managers patrol, rest. Pump fuel tank must be filled once a week grease, the bearings must not operate without grease, otherwise, noise, bearing fever, severe damage to the bearings, forcing the pump to stop running. Due to continuous operation of the pump 24 hours a day, the packing at the packing becomes easily heated and becomes softened, so that a large amount of sewage overflows there. Therefore, the packing must be changed once every 2-3 weeks at a time. However, it must be pointed out that when filling is replaced, the inlet valve must be closed first. Some inlet valves are manually operated and are very clumsy. Managers are laborious and labor-intensive refers to this work. Not to mention some manual valve in case immortality, you can not change the normal filling of the pump, resulting in the illusion of the pump can not work properly. At the same time, a large number of sewage overflow affect the working environment between pumps, smelly, so had to stop the pump. The most potentially dangerous job is pumping station managers to open the pump working hole to check whether the pump impeller wound, you must strictly enforce a set of complex safety procedures, such as filling down the work ticket, the use of hydrogen sulfide monitor , Wear gas masks and so on. Imagine wearing a gas mask stuffy and hot, but also make a lot of force to remove the garbage on the impeller within a certain period of time, is indeed very inconvenient. Without these safety measures, a certain concentration of hydrogen sulfide gas may accumulate in the pump and may escape at any time, resulting in a hydrogen sulfide gas poisoning accidental to human safety. Due to long-term sewage treatment, many pumping station managers have different levels of skin irritation, itch and other reactions, in the winter and the twilight even more feel very uncomfortable. When using a large submersible sewage pump such as the FLYGT-C pump, the pumping station manager can only monitor and record correctly in time through the instrumentation of the control cabinet on the ground. Because the pump is immersed in water only, the medium (water) delivered by the pump plays a role of sound insulation, which greatly reduces the noise and improves the working environment of the pump station. As the pump is put into operation, its oil (grease) has been fully filled in the normal operation, do not need to add grease (grease) work. Not only that, pump operation and management in the MF (MN) pump without the necessary operation, maintenance, inspection requirements. This is a major innovation in the daily management of the MF (MN) pump. Fourth, concluding remark Sewage pumping station pumping work, I deeply appreciate the "science and technology are the primary productive forces," the brilliant theory. In the ever-changing modern science and technology today, sewage pumping stations in order to fierce competition in the market to gain a firm foothold, we must vigorously promote the use of large submersible pumps such as FLYGT-C pumps. Although the prices are a little more expensive, in the long run, they can indeed reduce the labor intensity of pumping station managers, improve the operation rate of pumps, ensure the completion of sewage transmission and interception tasks and achieve double harvest of economic and social benefits. Therefore, such as FLYGT-C pumps and other large submersible sewage pump sewage pump station is the best choice.