Working principle of sewage submersible pump

Submersiblepump is also called submersible electric pump, English name submersiblepump. Submersible pump is a widely used water treatment tool, whether in agricultural production or industrial processing can see the shadow of submersible pump. According to its application occasions and uses can be roughly divided into submersible sewage pump, sand drainage submersible pump, water submersible pump. Submersible pump is generally composed of pump body, water pipe, pump seat, submersible motor and starting protection device. Popular is a pump and motor combined into one liquid conveying machinery, its structure is simple, easy to use. Submersible pump development has been more than 60 years of history, 1904, the United States of The Brown * Jackson (ByronJackson) company successfully designed the first horizontal connection submersible pump and submersible motor, this is the modern submersible pump "ancestor". With the development of material science, sealing technology, control and protection technology and the improvement of cold and hot processing technology level, submersible pump has been rapid development. In 1928 the company invented the direct connected vertical submersible pump, which is the first form of modern deep well submersible pump. In 1958, Shanghai People's Electric Machine Factory began to produce 7KW submersible pump, which opened the prelude of submersible pump production in China. After more than 30 years of development, great achievements have been made.

According to the relative position of the pump and the motor, the submersible pump can be divided into upper pump type and lower pump type. The upper pump submersible pump pump is above, the motor is below, this structure greatly reduces the radial size of the pump, so it is used for well submersible pump and small operation submersible pump. Under the pump submersible pump motor in the above, the pump below, it is divided into two types of built-in and external installation. The liquid delivered by the pump submersible pump first passes through the annular channel surrounding the motor, and then flows out of the pump pressure outlet after cooling the motor. Even in the case of close to drain suction pool, the pump does not have to worry about motor heating, so the application scope is increasingly expanding. The submersible pump is directly discharged from the outlet of the pressure chamber or guide vane after the impeller, and the motor is cooled by the liquid pumped. Because the pump structure can also work in shallow liquid, it is often used in operating surface submersible pump, especially it is the main structure of large caliber submersible pump. The mechanical seal of the submersible pump is located in the high-pressure area of the outlet flow. The higher the head, the higher the water pressure here, so the performance of the mechanical seal is controlled by the head.

Submersible pump according to its impeller structure characteristics of different applications are different.

Open or semi-open impeller: made of anti-wear material, with adjustable guide vane and screen. Widely used in construction sites, caves, harbors, factories, ships and other water supply and drainage or water injection, can be pumped containing abrasive such as clay, sand, gravel, drilling cuttings and other liquid media. Mobile structure, can be started in water, can meet the large flow, high head, limited space or explosive environment and other special requirements.

Non-clogging closed flow channel impeller, with good reliability and high efficiency, is mainly used for pumping sewage and mud in urban pumping stations and sewage treatment plants, pumping cooling water, waste water, corrosive media in industrial processes, continuous drainage in construction sites and large factories, etc. It is very suitable for pumping medium containing long fiber and large solid particles. Installed in small and simple pumping stations, hidden underground, the pump can be quickly and easily mounted on a rail or rope and down to the pump pit.

Open impeller with S-type cutter, with pumping, cutting and mixing functions. Good reliability and high efficiency. Mainly used for agricultural pumping liquid manure, can be broken dry solid, straw and other long fiber material, spiral impeller inlet can make thick inhaled manure into the pump, a total of four specifications. Compact structure, mounted on a guide rail in the manure tank, can also be installed in the storage tank, can be used in conjunction with the submersible stirrer.

Multi - bladed closed impeller, cast in cast iron or stainless steel, one side or two sides (double suction) water. Especially suitable for agricultural irrigation and various industrial applications, such as water supply, process water, spray and cooling water, etc. It can meet the needs of high head and large flow, flow up to 2000m3/h, head up to 110m, suitable for pumping clean water or slightly polluted water, there are a variety of specifications and structure types. Strong function, high reliability, easy installation and maintenance.

Adjustable blade axial flow impeller, with the characteristics of high efficiency and energy saving. Mainly used for agriculture, urban water supply and drainage and industrial pumping cooling water, etc., and can be used to control the inland river waterway system. It can meet the special needs of low head and large flow, and is suitable for pumping clean water or mildly polluted water.

Compact and simple structure, no special installation is required, just drop onto the protruding shoulder of the shell seat.

Open impeller with a cutting device at the entrance, made of chrome and stainless steel. Especially suitable for pressurized sewage systems, can be transported through only 40mm diameter pipe.

Closed runner impeller, matched with guide vane, good reliability. Widely used for water supply and drainage in cities, agriculture, ships, industry, etc., it can meet the needs of low head and large flow, the flow can reach 2000m3 to pump clean water or mildly polluted water, there are six specifications.

Simple installation and maintenance, no pipe connection design.

Open or closed flow channel impeller, made of anti-wear material. It is mainly used for pumping liquid containing abrasive particles such as drilling cuttings, sand, gravel and so on in mines, construction sites, caves, tunnels and DAMS. The suction end adopts adjustable rubber coating, which is conducive to operation at efficient points.

Open or closed impeller, with a plurality of blades. Mainly used for basement or other areas of ground drainage, also can be used for irrigation, can meet the needs of small flow and moderate head, suitable for pumping clean water or slightly polluted water, there are three specifications.

Compact structure, simple installation, just put the pump at the bottom of the pump pit.

Submersible pump models are very simple, usually only three sets of numbers. For example: 25-8-22, means: diameter of 25 mm, flow of 8 m3 / h, head of 22 m, power of 1.1 kW, speed of 2900 RPM, voltage of 380 V. General submersible pump voltage is 380 VOLTS, except for special pumps. Models range from 32-10-15, 40-15-30, 50-20-7 to 300-800-20.

Special attention should be paid to the type, flow and head of the submersible pump when selecting the type. If the selection is improper, it will not meet the requirements of the work and can not play the efficiency of the unit. Also make clear the direction of rotation of the submersible pump, although there are a lot of models of submersible pump positive and reverse can be water, but the reverse water yield will be small, the current increases, and sometimes even damage the motor winding. When installing submersible pump, cable should be overhead and power line should not be too long. When the unit is launched, do not make the cable stressed, so as not to cause the power line fracture. Submersible pump do not sink into the mud, otherwise it will lead to poor heat dissipation and burn out the motor winding. When starting the machine, try to avoid starting the machine under the condition of too low voltage. Too low voltage will reduce the speed. If not up to 70% of the rated speed, the start centrifugal switch will be closed, resulting in a long time to start the winding and heat up or even burn out the winding and capacitor. Do not frequently switch the motor, this is because the pump will produce backflow when stopped, if immediately started, the motor load will start, resulting in the starting current is too large and burned windings. The voltage is too high to boot, otherwise it will cause the motor overheating and burn out the motor winding. Do not let the pump overwork for a long time, do not pump water with large sand content, the time of dehydration of the electric pump should not be too long, so as not to overheat the motor and burn. During the operation of the unit, the operator must observe whether the working voltage and current are within the value specified on the nameplate at any time. If not, the motor should stop running to find out the reason and eliminate the fault. Usually to check the motor, such as cracks found under the cover, rubber seal ring damage or failure, should be replaced or repaired in time, in order to waterproof infiltration machine. During operation, the change of water level in the well should be observed frequently. The motor must not be exposed to the water or trapped in silt, so as not to affect the heat dissipation of the motor and burn out the windings. Should change with the water level in the well, lift the pump at any time, such as water reduction or interruption, should immediately find out the reason or stop the inspection. The cable should not rub against the well wall, lest the well water infiltrate into the motor along the cable core after the cable is worn out. After a year of use, should check the corrosion of the pump, and rust painting. If the submersible pump is not used for a long time, it should be carefully checked and kept in a dry and ventilated house.

China's submersible pump manufacturers have reached more than 5000, although it has gone through more than 30 years of development history, but compared with the world's first country submersible pump, there is still a big gap, our product varieties are not enough, the application field is relatively narrow. Water pump industry of our country in 2005 completed the industry's GDP totaled 16.6 billion yuan, from the overall water pump industry of our country economy running in good condition, and maintain a high growth for many years, but in our country every year a large number of water pump products to be imported from abroad, because our pump products, although in technology and foreign still has very big disparity, its reliability and quality is not stable enough. With the continuous development of socialist market economy and the continuous improvement of science and technology, our submersible pumps will play an increasingly important role in electromechanical drainage and irrigation, environmental protection, agricultural production, industrial processing and other parts. The main task facing the pump industry is to actively promote the localization of major equipment technology. We are convinced that our pump industry under the leadership of the Party, in the socialist construction of the road will go further and further, the more go better!