Abstract: A recovery cryostat, external to a cryogen storage tank, uses a cryocooler to condense vapor of cryogen from the storage tank and return the cryogen to the storage tank as a liquid. The process may be continuous or cyclical depending on the orientation of the recovery cryostat. If the recovery cryostat is located such that liquid can drain back to the storage tank, the process can be continuous. If the liquid cannot be drained back, a valve on the liquid return line is closed while the cryocooler condenses the vapor, a valve on the vapor supply line is then closed, the valve on the liquid return line is opened, and pressure in the recovery cryostat is increased to drive the liquid out. The storage tank is a type that can have vapor that boils off external to the tank be returned to the vapor space above the liquid in the tank.

Abstract: A circulating loop for transporting refrigeration to a remote location is connected serially between a Gifford-McMahon (GM) or GM type Pulse Tube cold head and the compressor. Either high pressure gas from the compressor can flow through the remote heat station before returning to the cold head or low pressure gas can flow from the cold head to the remote heat station before returning to the compressor. A first fraction of gas, which may include all of the gas at ambient temperature, enters a counter-flow heat exchanger, is cooled by the cold head, flows to the remote load, and then returns to ambient temperature as it flows through the counter-flow heat exchanger. The high or low pressure line may have a circulation control valve that diverts a second fraction of gas to flow directly between the cold head and compressor. A controller adjusts the circulation control valve to optimize the cooling of the load.

Abstract: A high separation efficacy, compact, bulk oil separator oriented horizontally and used with a scroll-type oil-lubricated compressor unit adapted to compressing helium. The horizontal bulk oil separator contains an integral oil reservoir and removes more than 99.9% of the oil from the helium that exits. The bulk oil separator contains successive chambers where oil separates from the gas by impingement.

Abstract: A high separation efficacy, compact, bulk oil separator oriented horizontally and used with a scroll-type oil-lubricated compressor unit adapted to compressing helium. The horizontal bulk oil separator contains an integral oil reservoir and removes more than 99.9% of the oil from the helium that exits. The bulk oil separator contains successive chambers where oil separates from the gas by impingement.