An exemplary system for dispensing foam includes a container holding a foamable liquid, a pump, and a suck-back device. The suck back device has a housing having a small bore with first diameter and a large bore with a second diameter; a dual body piston with a first piston that reciprocates in the small bore and a second piston that reciprocates in the large bore; a flow restrictor located proximate the dual body piston, a suck back chamber formed at least in part by the large bore and the second piston, and a foam outlet. The flow restrictor is configured so that fluid flow into the suck back device causes the suck back chamber to compress and when the fluid flow stops, a biasing member causes the suck back chamber to expand and suck back residual foam into the suck back chamber.

A liquid hydrogen pump for pumping liquid hydrogen stored in a hydrogen tank by pressurizing the liquid hydrogen is provided with a cylinder at least partially disposed in the hydrogen tank, a piston reciprocating inside the cylinder, the inside of the cylinder being pressurized by the piston, and a piston separating the inside of the cylinder from a pump chamber pressurized by the piston and an opposing chamber located on the opposite side of the pump chamber with the piston interposed therebetween, and a portion corresponding to the opposing chamber of the peripheral wall of the cylinder is formed with a recirculation opening for returning the liquid hydrogen flowing into the opposing chamber into the hydrogen tank.

A liquid hydrogen pump for pumping liquid hydrogen stored in a hydrogen tank by pressurizing the liquid hydrogen is provided with a cylinder at least partially disposed in the hydrogen tank, a piston reciprocating inside the cylinder, the inside of the cylinder being pressurized by the piston, and a piston separating the inside of the cylinder from a pump chamber pressurized by the piston and an opposing chamber located on the opposite side of the pump chamber with the piston interposed therebetween, and a portion corresponding to the opposing chamber of the peripheral wall of the cylinder is formed with a recirculation opening for returning the liquid hydrogen flowing into the opposing chamber into the hydrogen tank.

A tire sealant dispenser matches with an air compressor and contains a body in which chemical fluid (such as tire sealant) is filled, a cap connected on an opening of the body, a drive element configured to urge a punch element to pierce a film, such that an air conduit is in communication with a sealant conduit, pressurized air flows into the body via the air conduit from the air compressor, and the chemical fluid flows out of the sealant conduit.

A gas displacement assembly includes a storage container, a pump that pumps a pressurized gas material into the storage container, a cooling chamber that houses a coolant and cools the gas material to a cryogenic temperature, and a coolant line that transports coolant through the cooling chamber to cool the gas material.

A gas displacement assembly includes a storage container, a pump that pumps a pressurized gas material into the storage container, a cooling chamber that houses a coolant and cools the gas material to a cryogenic temperature, and a coolant line that transports coolant through the cooling chamber to cool the gas material.

A method for hydraulically fracturing a subterranean formation includes preparing and sending a first command signal from a master controller to a plurality of pumps of a pump system. The first command signal specifies a flow rate output for each in pump to achieve a first target flow rate for a fracturing fluid being injected into the subterranean formation. A pressure of the fracturing fluid injected into the subterranean formation at the first target flow rate is monitored and, based on the pressure, the master controller determines when to increase a flow rate of the fracturing fluid to a second target flow rate. The master controller prepares and sends a second command signal to the plurality of pumps to specify the flow rate output for each pump to achieve the second target flow rate.

A method for hydraulically fracturing a subterranean formation includes preparing and sending a first command signal from a master controller to a plurality of pumps of a pump system. The first command signal specifies a flow rate output for each in pump to achieve a first target flow rate for a fracturing fluid being injected into the subterranean formation. A pressure of the fracturing fluid injected into the subterranean formation at the first target flow rate is monitored and, based on the pressure, the master controller determines when to increase a flow rate of the fracturing fluid to a second target flow rate. The master controller prepares and sends a second command signal to the plurality of pumps to specify the flow rate output for each pump to achieve the second target flow rate.

A pump for a liquid product including a body inwardly delimiting a compression chamber, in which a piston is mounted sliding, as well as an external motor coupled to the piston for movement thereof by a piston rod passing through a wall secured to the pump body, through a passage opening equipped with a sealing device including a stack of seals kept gripped axially against the pump body, the sealing device including an axial compression member inserted between a crown, included in the sealing device, and the wall secured to the pump body.

A system and a method for cooling a prime mover and lube oil, comprising: a prime mover configured to drive a pump with a motor shaft; a prime mover cooling assembly that encases the prime mover, wherein the prime mover cooling assembly comprises: an air intake and an exhaust ventilator mounted above the prime mover; and a lube oil cooling assembly mounted above the prime mover, wherein the lube oil cooling assembly cools lube oil circulating within the pump and is mounted above the prime mover such that the lube oil cooling assembly does not hang off one or more sides of the prime mover and prime mover cooling assembly.