Hello:
1. There are too many models of centrifugal pumps. Let me briefly introduce what I know. Our national pump product model compilation consists of four parts. The method is as follows:
Ⅰ Ⅱ Ⅲ Ⅳ
The first part represents the suction inlet diameter of the pump, which is expressed in Arabic numerals in millimeters, such as 80, 100, etc.
The second part represents the basic structure, characteristics, uses and materials of the pump. Use the prefix of Chinese pinyin letters to mark, such as S for single-stage double-suction centrifugal water pump; D for segmented multi-stage centrifugal pump; F for corrosion-resistant pump; Y for single-stage centrifugal oil pump; R for hot water pump, etc.
The third part represents the lift and stage of the pump, which is expressed in Arabic numerals in mH2O.
The fourth part represents the deformed product of the pump. The three uppercase Chinese pinyin letters A, B, and C represent the first and second cutting of the impeller respectively.
For example: 250D--60x6 means a segmented multi-stage centrifugal pump with an inlet and outlet nominal diameter of 250 mm, a single-stage lift of 60 meters of water column, and a 6-stage number. Another example: 100R--37A means a hot water centrifugal pump with an inlet and outlet nominal diameter of 100mm, a head of 37 meters of water column, and an impeller that has been cut for the first time.
2. IS pump model preparation: (IS pump is still a single-stage single-suction cantilever centrifugal pump)
Ⅰ Ⅱ----III---IV Ⅴ
The first part: represents the name of the pump, represented by IS;
The second part: represents the suction inlet diameter of the pump, expressed in mm, represented by Arabic numerals.
The third part: represents the diameter of the discharge port of the pump, in mm, expressed in Arabic numerals.
Part 4: Represents the nominal diameter of the pump impeller, expressed in mm and expressed in Arabic numerals.
Part 5: Represents the deformed product of the pump, represented by the three letters A, B, and C.
For example: IS65--50--160A means a single-stage single-suction centrifugal pump with a suction port diameter of 65mm, a discharge port diameter of 50mm, a nominal impeller diameter of 160mm, and the impeller has been cut for the first time.
There are too many models of centrifugal pumps, so I won’t introduce them one by one. I hope you can check the manual of the water pump factory.
3. The benefits of using multi-stage compression for reciprocating compressors are as follows:
1: Reduce power consumption and improve the economy of the compressor. The more stages, the closer Isothermal cycle, that is, the compressor is more economical.
2: Improve cylinder volume utilization. When the suction pressure is constant, the greater the pressure ratio, the higher the discharge pressure. Due to the existence of clearance volume, the volume of high-pressure gas remaining in the clearance expands The larger it is, the smaller the suction volume will be and the volume coefficient will be lowered, thus reducing the exhaust volume. If multi-stage compression is used, the more stages there are, the smaller the pressure ratio, and the volume coefficient of the corresponding stages can be increased, thereby achieving reasonable utilization of the working volume of the cylinder.
3: Avoid excessive temperature. When the suction temperature and pressure are constant, the higher the pressure ratio, the higher the discharge pressure, and the higher the discharge temperature. This will worsen or even destroy the performance of the lubricating oil in the cylinder, accelerate parts wear, and shorten the service life. In addition, when the gas temperature rises, the lubricating oil is easy to decompose, which may cause the compressor to explode in severe cases. Therefore, the final temperature is generally controlled to be 20 to 50 degrees Celsius lower than the flash point of the lubricating oil. In multi-stage compression, because the pressure ratio is reduced, excessive temperature can be avoided.
4: Reduce the maximum force acting on the piston and improve the uniformity of the force on the operating mechanism.