High-pressure multi-stage pump start-up process: 1) Open the high-pressure multi-stage pump inlet valve, slightly open the vent valve to be vent to see the oil, and no gas, close the vent valve; The hydraulic pressure is greater than 0.25MPa, adjust the pressure of high-pressure motor lubricating oil 0.01 ~ 0.05MPa, back to normal lubricants branch; 3) Wear good labor insurance products, ready for related tools; 4) Check the reaction feed multistage pump inlet and outlet processes , The raw material tank level to meet the open multi-stage pump requirements; 5) open the reaction feed multi-stage pump back to the raw material tank process, notify the opening of the return tank regulator valve opening of not less than 40% (to meet the multistage pump minimum flow is not less than 66 tons / hour), the external operation site to confirm the normal opening; 6) check the oil station oil level is appropriate, the oil sample analysis qualified, filter oil filter pressure, pressure switch, Cooler flow is normal, and put into use; 7) inspection machine multi-stage pump, pressure gauge, wheel cover, wheel bolts, anchor bolts, valves, pipe flange gasket integrity; 8) Prime pump conditions are full Foot, interlocking reset within the operation, observed in the DCS multi-stage reaction pump feed multi-stage pump conditions to meet the conditions; 9) Manual turning two laps, high pressure multi-stage pump without unevenness of the phenomenon.