A high-pressure pump is configured to pressurize fuel. The high-pressure pump includes a relief valve device that is placed in a relief passage, which has one end part connected to a discharge passage in a housing while another end part of the relief passage is configured to be communicated with a suction passage in the housing. The discharge passage is configured to conduct the fuel, which is pressurized in and discharged from a pressurizing chamber. The relief valve device is configured to enable or limit a flow of the fuel between one side of the relief passage, at which the discharge passage is located, and another side of the relief passage, which is opposite to the discharge passage, at a valve opening time or a valve closing time of the relief valve device.

A pushrod assembly 5 may include a seal carrier 50 for a spaced seal assembly 60 and/or a seal carrier 70 for a stacked seal assembly 74, the spaced seal assembly including first and second annular seals 61, 62 separated by a spacer 63 to isolate between the seals a vented region 28 of the pushrod housing 6, the stacked seal assembly including at least two annular seals 80 stacked on the seal carrier. Each seal assembly can be removed and replaced via an access end 52, 72 of the seal carrier after detaching the access end from an adjacent component of the assembly. The seal carriers may be incorporated into a cryogenic pump 2 wherein at least one annular seal is arranged on each seal carrier to seal the pushrod assembly 5 within its housing 6.

A pushrod assembly 5 may include a seal carrier 50 for a spaced seal assembly 60 and/or a seal carrier 70 for a stacked seal assembly 74, the spaced seal assembly including first and second annular seals 61, 62 separated by a spacer 63 to isolate between the seals a vented region 28 of the pushrod housing 6, the stacked seal assembly including at least two annular seals 80 stacked on the seal carrier. Each seal assembly can be removed and replaced via an access end 52, 72 of the seal carrier after detaching the access end from an adjacent component of the assembly. The seal carriers may be incorporated into a cryogenic pump 2 wherein at least one annular seal is arranged on each seal carrier to seal the pushrod assembly 5 within its housing 6.

A liquid carbon dioxide delivery pump with a pump head including a pump chamber and a refrigerant channel different from a channel passing through the pump chamber, a circulation channel for refrigerant, a refrigerant pump arranged on the circulation channel, the refrigerant pump for causing the refrigerant to circulate through the circulation channel, and a cooling section arranged on the circulation channel, at a position away from the pump head, the cooling section being configured to cool the refrigerant passing through the circulation channel. The liquid carbon dioxide delivery pump further has a temperature sensor for detecting an ambient temperature of the pump head or a temperature of the pump head, and a refrigerant pump control section for adjusting, based on a detection signal of the temperature sensor, a flow rate of the refrigerant pump such that liquid carbon dioxide flowing through the pump head at a specific temperature.

A liquid carbon dioxide delivery pump with a pump head including a pump chamber and a refrigerant channel different from a channel passing through the pump chamber, a circulation channel for refrigerant, a refrigerant pump arranged on the circulation channel, the refrigerant pump for causing the refrigerant to circulate through the circulation channel, and a cooling section arranged on the circulation channel, at a position away from the pump head, the cooling section being configured to cool the refrigerant passing through the circulation channel. The liquid carbon dioxide delivery pump further has a temperature sensor for detecting an ambient temperature of the pump head or a temperature of the pump head, and a refrigerant pump control section for adjusting, based on a detection signal of the temperature sensor, a flow rate of the refrigerant pump such that liquid carbon dioxide flowing through the pump head at a specific temperature.

Systems and methods for pumping carbon dioxide in a chromatography system include an actuator that receives and compresses carbon dioxide at or above room temperature at a given pressure to put the carbon dioxide in or near supercritical form. This actuator can be a pre-pump disposed on the intake side of a pumping system. Alternatively, this actuator can be a primary actuator in the pumping system. The actuator includes an intake chamber that receives the carbon dioxide and a movable plunger extending into and closely received by the intake chamber. The plunger has a diameter and stroke length adapted to compress the carbon dioxide received by the intake chamber in sufficient volume at the given pressure to put the carbon dioxide in or near supercritical form at or above room temperature. A metered amount of the carbon dioxide in or near supercritical form can then be pumped.

Systems and methods for pumping carbon dioxide in a chromatography system include an actuator that receives and compresses carbon dioxide at or above room temperature at a given pressure to put the carbon dioxide in or near supercritical form. This actuator can be a pre-pump disposed on the intake side of a pumping system. Alternatively, this actuator can be a primary actuator in the pumping system. The actuator includes an intake chamber that receives the carbon dioxide and a movable plunger extending into and closely received by the intake chamber. The plunger has a diameter and stroke length adapted to compress the carbon dioxide received by the intake chamber in sufficient volume at the given pressure to put the carbon dioxide in or near supercritical form at or above room temperature. A metered amount of the carbon dioxide in or near supercritical form can then be pumped.

A vaporization device, including a fluid supply containing a vaporizable fluid; a plurality of bubble pumps operative to pump fluid from the fluid supply to outlets of the bubble pumps; and a fluid vaporization heater located adjacent the outlets of the bubble pumps to receive fluid from the bubble pumps.

A vaporization device, including a fluid supply containing a vaporizable fluid; a plurality of bubble pumps operative to pump fluid from the fluid supply to outlets of the bubble pumps; and a fluid vaporization heater located adjacent the outlets of the bubble pumps to receive fluid from the bubble pumps.

A check valve with improved response time comprises a valve member which has a central portion of a substantially convex shape and a guide portion that surrounds the central portion. The central portion has a central convex curvature extending towards the outlet port of the check valve, in the direction of the fluid flow. The guide portion has a weight to area ratio that is smaller than the weight to area ratio of the central portion. Such a check valve has an overall reduced weight of the valve member allowing a faster response time when the valve switches between its closed and open positions.