A piston rod and piston head are the driven components within a pump. An upstream end of the piston rod is attached within an aperture of the piston head. At least one flute extends between the upstream end of the piston rod and the aperture, and the at least one flute is configured to provide a flowpath for a fluid, such as paint, to flow downstream of the piston head and piston rod. The flutes facilitate a smooth downstream flow of the fluid, thereby reducing hydraulic resistance and reducing wear caused by the fluid.

A piston is the driven component within a pump. The piston is driven along a longitudinal axis to pump a fluid through the pump. The fluid flows through the piston between an upstream end of the pump and a downstream end of the pump. The piston outputs the fluid into the downstream end of the pump at a vector offset from the longitudinal axis, thereby inducing rotation of the piston throughout the pumping process. Rotating the piston encourages even wear on various components within the pump, such as sealing rings surrounding the piston, thereby increasing the lifespan of the components and increasing the efficiency of the pump.

An exhaust air conduit for a pneumatically powered pump, in particular, from a coating agent pump in a painting plant, is provided. The conduit includes an inlet for receiving the exhaust air from the pump, an outlet for discharging the exhaust air, and an exhaust air channel in which the exhaust air flows from the inlet to the outlet of the exhaust air conduit, and a housing member in which the exhaust air channel extends. A first thermal insulation element is provided in the region of a direction change of the exhaust air channel, in order to prevent an accumulation of the exhaust air directly at the inner wall of the exhaust air channel and thereby to lessen the cooling of the housing member.

A discharge valve for a hydraulic pump of a hydraulic unit defines a valve port, and includes a valve body and a receiving element. The valve body is configured to seal off the valve port. The receiving element adjoins the valve port, and defines a cavity configured to receive the valve body. The cavity has a longitudinal axis and an inner wall with a radially outwardly oriented pocket configured to receive the valve body.

A reciprocating pump comprises a cylinder, an inlet check valve, a piston, an outlet check valve and a purge circuit. The cylinder has a first end and a second end. The inlet check valve is disposed proximate a first end of the cylinder. The piston is disposed within the cylinder between the inlet check valve and the second end. The outlet check valve is disposed within the piston. The purge circuit extends across the inlet check valve and the outlet check valve to fluidly couple the first end and the second end.

An electromagnetic pump including a piston, an electromagnetic portion that moves the piston forward, and a spring that moves the piston backward. The piston including a discharge check valve built in the piston. The piston is formed with a hollow portion that opens in an inner peripheral portion of an end surface of the piston, and a spring receiving surface formed on an outer peripheral portion of the end surface to receive the spring. The discharge check valve is fixed through plastic deformation of the piston by inserting the discharge check valve into the hollow portion from an opening of the piston, and partially pressing a portion of the spring receiving surface of the piston on an inner peripheral side after the insertion to recess the spring receiving surface and elevate an inner peripheral surface of the piston surrounding the hollow portion.

Valve assemblies and related pumps, plungers, lift assemblies, and methods may include an insert disposed in an internal flow path of a plunger. The insert includes protrusions, each individually extending into the internal flow path of the plunger and converging at an apex of the insert to define a cage in which the restriction element is configured to move axially through the internal flow path.

A downhole tool comprises a cylinder, piston, and piston rod, the piston rod comprising first and second ends, the first end being external to the cylinder and having the capacity to be operatively connected to a sucker rod string or a sucker rod pump, the second end being positioned within a sealed cylinder chamber and attached directly or indirectly to the piston. The cylinder confining fluid within the cylinder chamber. The piston is coaxially positioned within the cylinder chamber such that the piston and cylinder share a central longitudinal axis. The piston and cylinder each comprise respective sidewalls, the respective sidewalls defining a lateral space between the piston and the cylinder. The lateral space and a piston conduit have the capacity to permit the fluid to move from a first chamber to a second chamber and to permit the fluid to move from the second chamber to the first chamber.

A downhole tool comprises a cylinder, piston, and piston rod, the piston rod comprising first and second ends, the first end being external to the cylinder and having the capacity to be operatively connected to a sucker rod string or a sucker rod pump, the second end being positioned within a sealed cylinder chamber and attached directly or indirectly to the piston. The cylinder confining fluid within the cylinder chamber. The piston is coaxially positioned within the cylinder chamber such that the piston and cylinder share a central longitudinal axis. The piston and cylinder each comprise respective sidewalls, the respective sidewalls defining a lateral space between the piston and the cylinder. The lateral space and a piston conduit have the capacity to permit the fluid to move from a first chamber to a second chamber and to permit the fluid to move from the second chamber to the first chamber.