The liquid medium transported by the reciprocating cryogenic pump is a low-temperature liquefied gas and the temperature range is -183 to -196°C. Therefore, in addition to the commonality of ordinary reciprocating cryogenic pumps, it also has characteristics closely related to cryogenic work.
1 Fluid end (pump head) section
(1) The hydraulic end is in a low temperature environment. The material used is copper material and stainless steel or solid lubricating material. The contact surface requires high precision. Be careful not to injure.
(2) For parts used for assembly, grease and moisture must be strictly removed to prevent dust from entering the pump interior.
(3) For the low-temperature part, it is necessary to do a good job of adiabatic cooling, and it should try to avoid intrusion of external heat. The vacuum jacket must not be damaged.
(4) The exhaust pipe should be unobstructed and the caliber should be large enough so that the vaporized gas can be discharged in time to prevent the gas from entering the pump cylinder.
(5) The sealing surfaces of the inlet and outlet valves should be closely and evenly sealed. No severe leakage should occur after the air tightness test. A simple kerosene test can also be used to prevent leaks. After the test, grease must be removed.
(6) When installing the piston, guide ring and piston rod, do not damage the sealing surface. Note that the mirror surface of the cylinder liner is clean and smooth.
(7) Pay attention to the seal surface of the sealer, make it flexible and leak-free, and use ice-free and frost-free during operation.
(8) All gaskets should be annealed. After repeated use three times, they must be annealed and reused. Avoid scratching the sealing surface during installation and storage of seals and sealing surfaces. When the tightening screw is tightened, the force should be uniform. To tighten the surface symmetrically, do not apply force unilaterally so that the screws press the cover evenly.
(9) Retighten fasteners should be strictly prohibited under low temperature operating conditions.
2 body (box)
(1) It must be installed in accordance with the relevant technical conditions, continuously variable transmission, electromagnetic speed controller and transmission mechanism, and to ensure the accuracy of moving parts.
(2) Pay attention to the lubrication conditions and the oil level of the lubricant.
(3) Pay attention to the degree of winding of the piston rod during installation, and pay attention to the degree of coaxiality. Make sure that the piston rod and the sealing friction surface have a good working condition during the reciprocating movement.
(4) When installing, avoid the oil from the drive end entering the hydraulic end (pump head).