The requirement of the pump for the industrial plant has the following three points: (1) It must meet the requirements of process parameters such as flow rate, head, pressure, temperature and NPSH. (2) The characteristics of the medium must be satisfied. ①for the transport of flammable, explosive, toxic or expensive medium pump, shaft seal reliable or require the use of leak-free pumps, such as shielded pumps, magnetic drive pumps, diaphragm pumps. ② on the delivery of corrosive media pump, requiring over-current components using corrosion-resistant materials. ③ on the transport of solids containing solids pump, requiring over-current components wear-resistant materials, if necessary, the seal should be used Qingguo liquid rinse. (3) Must meet the site installation requirements. ①For installation in the presence of corrosive gases pump, require anti-atmospheric corrosion measures. ② installed in outdoor temperature below -20 ℃ pump, pump cold requires consideration of the phenomenon of cold, low temperature materials. ③ installed in the explosive area of ​​?? the pump, should be based on the level of dangerous areas, the use of explosion-proof motor. (4) For factories that require major overhauls every year, the pump's continuous operating cycle should generally not be less than 8000h. In order to meet the requirements of 3-year major overhaul, APl610 (10 version) provides that the continuous operation cycle of pumps for petroleum, petrochemical and natural gas industries shall be at least 3 years. (5) The design life of the pump is generally at least 10 years. APl610 (f910 version) provides the design life of centrifugal pumps for the petroleum, petrochemical and natural gas industries for at least 20 years. (6) The design, manufacture and inspection of the pump shall comply with the relevant standards and norms. The common standards and norms are shown in Table l-3. (7) The pump factory should ensure that the pump performance in the power supply voltage, frequency range. Specific changes in the range: voltage 380V + _10%, 3000V ± 10%, 6000V_ + 10%; frequency 50Hz + _1Hz. (8) When determining the type and manufacturer of the pump, consider factors such as pump performance, energy consumption, reliability, price and manufacturing specifications. Pump Name Features Selection Requirements Feed pump (including raw material pump and intermediate feed pump) (1) Flow stability (2) Higher general head (3) Some materials with larger viscosity or with solid particles (4) Pump inlet temperature is generally However, some intermediate feed pump inlet temperature can be greater than 100 ℃ (5) Can not stop while working (1) Centrifugal pump is generally used (2) High lift, consider using positive displacement pump or high speed pump (3 ) The pump standby rate of l00% return pump (including the top, middle and bottom of the return pump) (1) large flow range, low lift (2) pump inlet temperature is not high, usually 30 ℃ -60 ℃ 3) high reliability of work (1) the general selection of centrifugal pumps (2) the pump standby rate of 50% -100% Bottom pump (1) large flow range (generally with liquid level control flow) (2) Large (3) pump inlet temperature is higher, generally greater than l00 ℃ (4) liquid is generally in the gas-liquid two phase (5) high reliability of the work (6) harsh working conditions, the general precipitation of dirt (1) Pump (2) selection of low cavitation allowance pump, and the necessary perfusion head (3) the pump standby rate of l00% circulating pump (1) steady flow and low lift (2) A wide range of media (1) the selection of centrifugal pumps (2) according to media selection of pump models and materials (3) the pump standby rate of 50% ~ l00% Products Pump (1) smaller flow (2) Pump inlet temperature is low (overhead products are generally room temperature, the middle of the bottom and the bottom of the product temperature is slightly higher) (4) intermittent operation of some products pump (1) should use a single-stage centrifugal pump (2) of high purity or precious products, Requires a reliable seal, the pump standby rate of l00%, for general products, the standby rate of 50% ~ l00%. For intermittent operation of the product pump, the pump is generally not equipped with a pump (1) flow is very small, strict measurement requirements (2) work at room temperature (3) discharge pressure is higher (4) injection of chemicals for the medium, often corrosive (1) the choice of plunger or diaphragm metering pump (2) of a corrosive medium, the pump overcurrent components are generally used corrosion-resistant materials (3) general intermittent operation, not equipment pump sewage pump (1) (2) Corrosive media and abrasive particles are often found in the wastewater (3) Control flow rate is required for continuous delivery (1) Selection of sewage pump and slurry pump (2) 50% ~ l00% fuel pump (1) flow is small, the pump outlet pressure is stable (usually 1.O ~ 1.2MPa) (2) high viscosity (3) the pump population temperature is generally not high (1) Viscosity, optional rotor pump or centrifugal pump (2) the pump standby rate of l00% lube pump and seal pump (1) lube oil pressure is generally 0.1 ~ 0.2MPa (2) mechanical seal seal liquid pressure than the seal chamber pressure High 0.05 ~ 0.15MPa (1) generally with the host supporting the supply (2) is generally a screw pump and gear pump, but the large centrifugal compressor Concentrated oil tend to use centrifugal pumps
