Equipment Rehabilitation
Cryogenic Pumps
Losing prime, short on flow, or leaking at the seals?
What we do
- Rebuilds and overhauls
- Seals, bearings and pistons replaced
- Tested before it goes back
Done through partner shops matched to your equipment — one point of contact from quote to delivery.
Frequently Asked Questions
Cryogenic Pumps questions
Why does my cryogenic pump lose prime or cavitate?
Cavitation is the liquid boiling inside the pump because its pressure drops below vapor pressure. Common causes are not enough suction pressure (NPSH), liquid that's picked up heat, closed or partly closed feed and return valves, low tank level and clogged suction filters. An insulated suction line helps prevent it.
Sources: EIGA Doc 159 · Fluensys
Why does a reciprocating cryogenic pump need cooldown before starting?
Its plastic piston rings shrink and grow far more than the metal around them, so starting warm wears rings and can overheat parts. Guidance says the whole cold end must be cold first, and many installs use an interlock that blocks a warm start.
Sources: AIGA 089/14 · EIGA Doc 159
What are the signs a reciprocating pump needs a cold-end rebuild?
Flow or pressure below normal, leaking piston gland seals, or a noisy pump. Once supply, valves and filters are ruled out, low output can mean damaged or leaking suction or discharge valves; seal leaks are checked against seal wear and running hours.
Source: EIGA Doc 159
Why not keep running a pump with a leaking seal or one that keeps losing prime?
Cold liquid leaking past worn seals has made warm-end parts brittle and fail, and in oxygen service has caused fires. Running on vapor can overheat and damage the pump — which is why guidance calls for a loss-of-prime shutdown.
Sources: AIGA 089/14 · EIGA Doc 159
What's the difference between a reciprocating and a centrifugal cryogenic pump?
A reciprocating (piston) pump gives nearly steady flow across a wide pressure range — high pressure, lower volume, like cylinder filling. A centrifugal pump is built for higher flow, with pressure dropping as flow rises; submerged centrifugal designs have no shaft seals and are used for LNG fueling and microbulk delivery.
Sources: Pumps & Systems · Cryostar HP pumps · Cryostar submerged pumps
Can a pump be switched between nitrogen, argon and oxygen service?
It depends on the manufacturer and the pump model — contact the manufacturer before changing service. As a general rule, oxygen service requires every wetted part to be cleaned for oxygen service and verified, and the pump built so leaking oxygen can't reach lubricant. On LNG specifically: that call is ours, not a manufacturer or code requirement — we treat pumps built for LNG as staying in LNG service.
Sources: EIGA Doc 159 · CGA G-4.1
What should I send for a pump rebuild quote?
Make, model and serial; the product it pumps (LIN, LOX, LAR or LNG); running hours; and what you're seeing — low flow, seal leakage, noise or loss of prime. Say if it's been in oxygen service, since those parts need special cleaning and handling.
Source: EIGA Doc 159
Answers are general guidance, with sources linked so you can check them. Your equipment's manufacturer and the rules that apply to your site always come first.
Get a quote
Tell us what you have and what's wrong. We'll come back with next steps and a realistic idea of cost.