PISTON PUMPSPiston pump

The Pump action is affected by a piston that moves in a reciprocating cycle through cylinder.The basic operation of piston pumps are very similar of that of the reciprocating enginesTypes of Piston PumpAxial piston pump Bent-axis-type piston pump. Swash-plate-type piston pump. Radial piston pump

In this type, the cylinder block and drive shaft are located on the same center line The pistons are connected to a shoe plate that bears against an angled swash plate As the cylinder rotates, the pistons reciprocate because the piston shoes follow the angled surface of the swash plate Swash-Plate-Type Piston Pump

The outlet and inlet ports are located in the valve plate so that the pistons pass the inlet as they are being pulled out and pass the outlet as they are being forced back in. The maximum swash plate angle is limited to 17.5 by construction Swash-Plate-Type Piston Pump

CYLINDER BLOCK AND PISTON

CYLINDER BLOCK AND PISTON

PISTON SHOE

ROTATING GROUP

PISTON PUMP PRINCIPLE

FIXED DISPLACEMENT PISTON PUMPQQ = (No. of Pistons) x (Piston Size) x (Piston Stroke) x (Drive Speed)

Q = (No. of Pistons) x (Piston Size) x (Piston Stroke) x (Drive Speed)QVARIABLE DISPLACEMENT PUMP - MAX FLOW

Q = (No. of Pistons) x (Piston Size) x (Piston Stroke) x (Drive Speed)QVARIABLE DISPLACEMENT PUMP - REDUCED FLOW

Q = (No. of Pistons) x (Piston Size) x (Piston Stroke) x (Drive Speed)STROKEQVARIABLE DISPLACEMENT PUMP - REDUCED FLOW

Q = (No. of Pistons) x (Piston Size) x (Piston Stroke) x (Drive Speed)QSTROKEVARIABLE DISPLACEMENT PUMP - ZERO FLOW

Q = (No. of Pistons) x (Piston Size) x (Piston Stroke) x (Drive Speed)STROKEVARIABLE DISPLACEMENT PUMP - ZERO FLOW

QVARIABLE DISPLACEMENT PUMP - REVERSED FLOW

Bent-axis-type piston pumpIt contains a cylinder block rotating with a drive shaft The center line of the cylinder block is set at an offset angle relative to the center line of the drive shaftThe cylinder block contains a number of pistons arranged along a circleThe volumetric displacement of the pump depends on the offset angle For a fixed displacement, units are usually provided with 23deg or 30deg offset angles

2005/2006 I.Hydraulic and Pneumatic Systems*Axial piston pumpsWith tilting block

Hydraulic and Pneumatic Systems

2005/2006 I.Hydraulic and Pneumatic Systems*Axial piston pumpsWith tilting block

Hydraulic and Pneumatic Systems

Radial Piston PumpIt has a number of radial pistons in a cylinder block which revolves around the stationary cam.In These Pumps the pistons move perpendicularly to the shaft centre line As the cylinder block rotates the eccentricity of cam causes as in and out or pumping motion of the piston

Review of Pumps

2005/2006 I.Hydraulic and Pneumatic Systems*Pump typesExternal gear pump

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2005/2006 I.Hydraulic and Pneumatic Systems*Pump typesOff-centered internal gear pump

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2005/2006 I.Hydraulic and Pneumatic Systems*Pump typesCentered internal gear pump / gerotor pump

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2005/2006 I.Hydraulic and Pneumatic Systems*Pump typesScrew pump

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2005/2006 I.Hydraulic and Pneumatic Systems*Pump typesVane pump

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2005/2006 I.Hydraulic and Pneumatic Systems*Pump typesRadial piston pump with stationary cylinder block

Hydraulic and Pneumatic Systems

2005/2006 I.Hydraulic and Pneumatic Systems*Pump typesAxial piston pump with tilting block

Hydraulic and Pneumatic Systems

2005/2006 I.Hydraulic and Pneumatic Systems*Pump typesAxial piston pump with tilting cam plate

Hydraulic and Pneumatic Systems

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