✖

Home

Stock Categories

Technical Articles

Rexroth THROTTLE VALVE

Rexroth Piston Pump

DENISON vane pump

Home>Products>Rexroth Piston Pump>Rexroth A10VSO71DR/31R-PPA12K01 Piston Pump

Rexroth A10VSO71DR/31R-PPA12K01 MODELS

Need a CAD or 3D Model?

Contact Now WhatsApp Be Our Agent

Rexroth A10VSO71DR/31R-PPA12K01 Piston Pump

Name: Rexroth A10VSO71DR/31R-PPA12K01 Piston Pump
Brand: Rexroth
SKU: A10VSO71DR/31R-PPA12K01
Rating: 4.9 (5 reviews)

Rexroth A10VSO71DR/31R-PPA12K01 SPECIFICATIONS

QuestionRexroth A10VSO71DR/31R-PPA12K01 Piston Pump ? 85 mm H Find what you 702 mm da min. need faster by entering your Rexroth Piston Pump information .
Brand Name:Rexroth
Model Number:
A10VSO71DR/31R-PPA12K01
Major Diameter [Max:75.0 LB
Pump Series:Flange Mount
Model No.:Left Hand (CCW)
Minor Diameter [Min:3520VQ25A12-1AA20LH
Pressure Port Size, Shaft End:3
Shaft Dia.:Flange
Cover End Flow @ RPM:5/16 in
Minor Diameter:Standard Pilot

Vane Pump CO., LTD.

Vane Pump CO., LTD.China

Vane Pump CO., LTD.2020-07-10 09:46:19
Welcome to my shop! Glad to serve you! Please send your question!

Interested In: Price Inspection Certificate Product Specifications Company Profile

Rexroth A10VSO71DR/31R-PPA12K01 Piston Pump Technology

Displacement Shaft End (cu in/revolution):1.25 in
Integral Valve Configuration:Straight w/ Key
Max. RPM [Max:3520VQ
Cover End RPM [Max:2 1/2 in
Minor Diameter [Max:Buna-N
Major Diameter [Min:2500
Shaft End RPM [Max:N/A
Seal Material:SAE C, 2 Bolt
Controlled Flow Rate:Single Shaft Seal
Weight:N/A
Spline Description:2500
Port Type:2500
Port Orientation - Cover End:N/A
Shaft Key:12 gal/min @ 1200 rpm, 18 gal/min @ 1800 rpm
Pressure Port Size, Cover End:N/A
Displacement Cover End (cu in/revolution):N/A
GPM @ 1,800 rpm, Cover End:N/A
Mounting Flange:N/A
Manufacturer Part No.:N/A
Rotation:25 gal/min @ 1200 rpm, 37.5 gal/min @ 1800 rpm
Shaft Length:3520VQ25A12-1AA20LH
Mounting:2300
Pilot Type:3000
Relief Valve Setting:18
Shaft End Pressure [Max:37.5
Cover End Pressure [Max:w/o Integral Valves
Port Orientation - Shaft End:Outlet 135° CCW from Inlet
Shaft Type:Outlet Opposite Inlet
GPM @ 1,800 rpm, Shaft End:3/4 in Flange
Shaft End Flow @ RPM:1 1/4 in Flange
Port Size:2.41
Shaft Seal Type:4.98

Rexroth A10VSO71DR/31R-PPA12K01 Rexroth A10VSO71DR/31R-PPA12K01 Piston Pump Details

Rexroth A10VSO140DFR1/32R-VPB12N00 Piston Pump	Port Type:75.0 LB; Minor Diameter:Flange Mount; Cover End Pressure [Max:Left Hand (CCW); Port Orientation - Shaft End:3520VQ25A12-1AA20LH; Spline Description:3; Seal Material:Flange; Port Orientation - Cover End:5/16 in; Pressure Port Size, Shaft End:Standard Pilot; Controlled Flow Rate:1.25 in; Shaft Type:Straight w/ Key; Pump Series:3520VQ; Shaft Length:2 1/2 in; Seal Material:Buna-N; Max. RPM [Max:2500; Minor Diameter:N/A; Mounting Flange:SAE C, 2 Bolt; Shaft Seal Type:Single Shaft Seal; Spline Description:N/A; Cover End RPM [Max:2500; Shaft End RPM [Max:2500; Controlled Flow Rate:N/A; Cover End Flow @ RPM:12 gal/min @ 1200 rpm, 18 gal/min @ 1800 rpm; Major Diameter [Max:N/A; Major Diameter [Min:N/A; Minor Diameter [Max:N/A; Minor Diameter [Min:N/A; Relief Valve Setting:N/A; Shaft End Flow @ RPM:25 gal/min @ 1200 rpm, 37.5 gal/min @ 1800 rpm; Manufacturer Part No.:3520VQ25A12-1AA20LH; Cover End Pressure [Max:2300; Shaft End Pressure [Max:3000; GPM @ 1,800 rpm, Cover End:18; GPM @ 1,800 rpm, Shaft End:37.5; Integral Valve Configuration:w/o Integral Valves; Port Orientation - Cover End:Outlet 135° CCW from Inlet; Port Orientation - Shaft End:Outlet Opposite Inlet; Pressure Port Size, Cover End:3/4 in Flange; Pressure Port Size, Shaft End:1 1/4 in Flange; Displacement Cover End (cu in/revolution):2.41; Displacement Shaft End (cu in/revolution):4.98;
Rexroth A10VSO100DR/31R-PPA12N00 Piston Pump	Major Diameter [Max:75.0 LB; Manufacturer Part No.:Flange Mount; Shaft Seal Type:Left Hand (CCW); Mounting Flange:3520VQ25A12-1AA20LH; Port Size:3; Port Orientation - Shaft End:Flange; Controlled Flow Rate:5/16 in; Integral Valve Configuration:Standard Pilot; GPM @ 1,800 rpm, Cover End:1.25 in; Minor Diameter [Max:Straight w/ Key; Pump Series:3520VQ; Shaft Length:2 1/2 in; Seal Material:Buna-N; Max. RPM [Max:2500; Minor Diameter:N/A; Mounting Flange:SAE C, 2 Bolt; Shaft Seal Type:Single Shaft Seal; Spline Description:N/A; Cover End RPM [Max:2500; Shaft End RPM [Max:2500; Controlled Flow Rate:N/A; Cover End Flow @ RPM:12 gal/min @ 1200 rpm, 18 gal/min @ 1800 rpm; Major Diameter [Max:N/A; Major Diameter [Min:N/A; Minor Diameter [Max:N/A; Minor Diameter [Min:N/A; Relief Valve Setting:N/A; Shaft End Flow @ RPM:25 gal/min @ 1200 rpm, 37.5 gal/min @ 1800 rpm; Manufacturer Part No.:3520VQ25A12-1AA20LH; Cover End Pressure [Max:2300; Shaft End Pressure [Max:3000; GPM @ 1,800 rpm, Cover End:18; GPM @ 1,800 rpm, Shaft End:37.5; Integral Valve Configuration:w/o Integral Valves; Port Orientation - Cover End:Outlet 135° CCW from Inlet; Port Orientation - Shaft End:Outlet Opposite Inlet; Pressure Port Size, Cover End:3/4 in Flange; Pressure Port Size, Shaft End:1 1/4 in Flange; Displacement Cover End (cu in/revolution):2.41; Displacement Shaft End (cu in/revolution):4.98;
Rexroth A10VSO140DFR1/31R-PPB12N00 Piston Pump	Port Orientation - Cover End:75.0 LB; Cover End RPM [Max:Flange Mount; Manufacturer Part No.:Left Hand (CCW); Relief Valve Setting:3520VQ25A12-1AA20LH; Model No.:3; Displacement Cover End (cu in/revolution):Flange; Pump Series:5/16 in; Shaft End Flow @ RPM:Standard Pilot; Integral Valve Configuration:1.25 in; Spline Description:Straight w/ Key; Pump Series:3520VQ; Shaft Length:2 1/2 in; Seal Material:Buna-N; Max. RPM [Max:2500; Minor Diameter:N/A; Mounting Flange:SAE C, 2 Bolt; Shaft Seal Type:Single Shaft Seal; Spline Description:N/A; Cover End RPM [Max:2500; Shaft End RPM [Max:2500; Controlled Flow Rate:N/A; Cover End Flow @ RPM:12 gal/min @ 1200 rpm, 18 gal/min @ 1800 rpm; Major Diameter [Max:N/A; Major Diameter [Min:N/A; Minor Diameter [Max:N/A; Minor Diameter [Min:N/A; Relief Valve Setting:N/A; Shaft End Flow @ RPM:25 gal/min @ 1200 rpm, 37.5 gal/min @ 1800 rpm; Manufacturer Part No.:3520VQ25A12-1AA20LH; Cover End Pressure [Max:2300; Shaft End Pressure [Max:3000; GPM @ 1,800 rpm, Cover End:18; GPM @ 1,800 rpm, Shaft End:37.5; Integral Valve Configuration:w/o Integral Valves; Port Orientation - Cover End:Outlet 135° CCW from Inlet; Port Orientation - Shaft End:Outlet Opposite Inlet; Pressure Port Size, Cover End:3/4 in Flange; Pressure Port Size, Shaft End:1 1/4 in Flange; Displacement Cover End (cu in/revolution):2.41; Displacement Shaft End (cu in/revolution):4.98;
Rexroth A10VSO140DR/31R-PPB12N00 Piston Pump	Cover End RPM [Max:75.0 LB; Spline Description:Flange Mount; Displacement Cover End (cu in/revolution):Left Hand (CCW); Shaft End RPM [Max:3520VQ25A12-1AA20LH; Controlled Flow Rate:3; Port Type:Flange; Weight:5/16 in; Mounting Flange:Standard Pilot; Minor Diameter:1.25 in; Cover End Flow @ RPM:Straight w/ Key; Pump Series:3520VQ; Shaft Length:2 1/2 in; Seal Material:Buna-N; Max. RPM [Max:2500; Minor Diameter:N/A; Mounting Flange:SAE C, 2 Bolt; Shaft Seal Type:Single Shaft Seal; Spline Description:N/A; Cover End RPM [Max:2500; Shaft End RPM [Max:2500; Controlled Flow Rate:N/A; Cover End Flow @ RPM:12 gal/min @ 1200 rpm, 18 gal/min @ 1800 rpm; Major Diameter [Max:N/A; Major Diameter [Min:N/A; Minor Diameter [Max:N/A; Minor Diameter [Min:N/A; Relief Valve Setting:N/A; Shaft End Flow @ RPM:25 gal/min @ 1200 rpm, 37.5 gal/min @ 1800 rpm; Manufacturer Part No.:3520VQ25A12-1AA20LH; Cover End Pressure [Max:2300; Shaft End Pressure [Max:3000; GPM @ 1,800 rpm, Cover End:18; GPM @ 1,800 rpm, Shaft End:37.5; Integral Valve Configuration:w/o Integral Valves; Port Orientation - Cover End:Outlet 135° CCW from Inlet; Port Orientation - Shaft End:Outlet Opposite Inlet; Pressure Port Size, Cover End:3/4 in Flange; Pressure Port Size, Shaft End:1 1/4 in Flange; Displacement Cover End (cu in/revolution):2.41; Displacement Shaft End (cu in/revolution):4.98;
Rexroth A10VSO100DFR1/32R-PPB12N00 Piston Pump	Displacement Cover End (cu in/revolution):75.0 LB; Shaft Seal Type:Flange Mount; Port Orientation - Cover End:Left Hand (CCW); Port Orientation - Shaft End:3520VQ25A12-1AA20LH; Major Diameter [Max:3; Mounting:Flange; Model No.:5/16 in; Max. RPM [Max:Standard Pilot; Cover End Flow @ RPM:1.25 in; Rotation:Straight w/ Key; Pump Series:3520VQ; Shaft Length:2 1/2 in; Seal Material:Buna-N; Max. RPM [Max:2500; Minor Diameter:N/A; Mounting Flange:SAE C, 2 Bolt; Shaft Seal Type:Single Shaft Seal; Spline Description:N/A; Cover End RPM [Max:2500; Shaft End RPM [Max:2500; Controlled Flow Rate:N/A; Cover End Flow @ RPM:12 gal/min @ 1200 rpm, 18 gal/min @ 1800 rpm; Major Diameter [Max:N/A; Major Diameter [Min:N/A; Minor Diameter [Max:N/A; Minor Diameter [Min:N/A; Relief Valve Setting:N/A; Shaft End Flow @ RPM:25 gal/min @ 1200 rpm, 37.5 gal/min @ 1800 rpm; Manufacturer Part No.:3520VQ25A12-1AA20LH; Cover End Pressure [Max:2300; Shaft End Pressure [Max:3000; GPM @ 1,800 rpm, Cover End:18; GPM @ 1,800 rpm, Shaft End:37.5; Integral Valve Configuration:w/o Integral Valves; Port Orientation - Cover End:Outlet 135° CCW from Inlet; Port Orientation - Shaft End:Outlet Opposite Inlet; Pressure Port Size, Cover End:3/4 in Flange; Pressure Port Size, Shaft End:1 1/4 in Flange; Displacement Cover End (cu in/revolution):2.41; Displacement Shaft End (cu in/revolution):4.98;
Rexroth A10VSO140DRS/32R-VPB12N00 Piston Pump	Pump Series:75.0 LB; Major Diameter [Min:Flange Mount; Pressure Port Size, Shaft End:Left Hand (CCW); Shaft Length:3520VQ25A12-1AA20LH; Relief Valve Setting:3; Minor Diameter:Flange; Shaft End Flow @ RPM:5/16 in; Cover End Flow @ RPM:Standard Pilot; GPM @ 1,800 rpm, Shaft End:1.25 in; Minor Diameter [Max:Straight w/ Key; Pump Series:3520VQ; Shaft Length:2 1/2 in; Seal Material:Buna-N; Max. RPM [Max:2500; Minor Diameter:N/A; Mounting Flange:SAE C, 2 Bolt; Shaft Seal Type:Single Shaft Seal; Spline Description:N/A; Cover End RPM [Max:2500; Shaft End RPM [Max:2500; Controlled Flow Rate:N/A; Cover End Flow @ RPM:12 gal/min @ 1200 rpm, 18 gal/min @ 1800 rpm; Major Diameter [Max:N/A; Major Diameter [Min:N/A; Minor Diameter [Max:N/A; Minor Diameter [Min:N/A; Relief Valve Setting:N/A; Shaft End Flow @ RPM:25 gal/min @ 1200 rpm, 37.5 gal/min @ 1800 rpm; Manufacturer Part No.:3520VQ25A12-1AA20LH; Cover End Pressure [Max:2300; Shaft End Pressure [Max:3000; GPM @ 1,800 rpm, Cover End:18; GPM @ 1,800 rpm, Shaft End:37.5; Integral Valve Configuration:w/o Integral Valves; Port Orientation - Cover End:Outlet 135° CCW from Inlet; Port Orientation - Shaft End:Outlet Opposite Inlet; Pressure Port Size, Cover End:3/4 in Flange; Pressure Port Size, Shaft End:1 1/4 in Flange; Displacement Cover End (cu in/revolution):2.41; Displacement Shaft End (cu in/revolution):4.98;
Rexroth A10VSO071DFR1/32R-VPB12N00 Piston Pump	Cover End RPM [Max:75.0 LB; Shaft Length:Flange Mount; Rotation:Left Hand (CCW); Shaft Type:3520VQ25A12-1AA20LH; Shaft End Pressure [Max:3; Pilot Type:Flange; GPM @ 1,800 rpm, Shaft End:5/16 in; Weight:Standard Pilot; Cover End Pressure [Max:1.25 in; Port Orientation - Cover End:Straight w/ Key; Pump Series:3520VQ; Shaft Length:2 1/2 in; Seal Material:Buna-N; Max. RPM [Max:2500; Minor Diameter:N/A; Mounting Flange:SAE C, 2 Bolt; Shaft Seal Type:Single Shaft Seal; Spline Description:N/A; Cover End RPM [Max:2500; Shaft End RPM [Max:2500; Controlled Flow Rate:N/A; Cover End Flow @ RPM:12 gal/min @ 1200 rpm, 18 gal/min @ 1800 rpm; Major Diameter [Max:N/A; Major Diameter [Min:N/A; Minor Diameter [Max:N/A; Minor Diameter [Min:N/A; Relief Valve Setting:N/A; Shaft End Flow @ RPM:25 gal/min @ 1200 rpm, 37.5 gal/min @ 1800 rpm; Manufacturer Part No.:3520VQ25A12-1AA20LH; Cover End Pressure [Max:2300; Shaft End Pressure [Max:3000; GPM @ 1,800 rpm, Cover End:18; GPM @ 1,800 rpm, Shaft End:37.5; Integral Valve Configuration:w/o Integral Valves; Port Orientation - Cover End:Outlet 135° CCW from Inlet; Port Orientation - Shaft End:Outlet Opposite Inlet; Pressure Port Size, Cover End:3/4 in Flange; Pressure Port Size, Shaft End:1 1/4 in Flange; Displacement Cover End (cu in/revolution):2.41; Displacement Shaft End (cu in/revolution):4.98;
Rexroth A4VSO125DR/30R-PPA13N00 Piston Pump	Shaft Type:75.0 LB; Minor Diameter [Max:Flange Mount; Shaft Length:Left Hand (CCW); Major Diameter [Min:3520VQ25A12-1AA20LH; Model No.:3; GPM @ 1,800 rpm, Cover End:Flange; Rotation:5/16 in; Displacement Shaft End (cu in/revolution):Standard Pilot; Shaft Seal Type:1.25 in; Shaft End Pressure [Max:Straight w/ Key; Pump Series:3520VQ; Shaft Length:2 1/2 in; Seal Material:Buna-N; Max. RPM [Max:2500; Minor Diameter:N/A; Mounting Flange:SAE C, 2 Bolt; Shaft Seal Type:Single Shaft Seal; Spline Description:N/A; Cover End RPM [Max:2500; Shaft End RPM [Max:2500; Controlled Flow Rate:N/A; Cover End Flow @ RPM:12 gal/min @ 1200 rpm, 18 gal/min @ 1800 rpm; Major Diameter [Max:N/A; Major Diameter [Min:N/A; Minor Diameter [Max:N/A; Minor Diameter [Min:N/A; Relief Valve Setting:N/A; Shaft End Flow @ RPM:25 gal/min @ 1200 rpm, 37.5 gal/min @ 1800 rpm; Manufacturer Part No.:3520VQ25A12-1AA20LH; Cover End Pressure [Max:2300; Shaft End Pressure [Max:3000; GPM @ 1,800 rpm, Cover End:18; GPM @ 1,800 rpm, Shaft End:37.5; Integral Valve Configuration:w/o Integral Valves; Port Orientation - Cover End:Outlet 135° CCW from Inlet; Port Orientation - Shaft End:Outlet Opposite Inlet; Pressure Port Size, Cover End:3/4 in Flange; Pressure Port Size, Shaft End:1 1/4 in Flange; Displacement Cover End (cu in/revolution):2.41; Displacement Shaft End (cu in/revolution):4.98;
Rexroth A4VSO250DR/30R-PPA13N00 Piston Pump	Cover End RPM [Max:75.0 LB; Pressure Port Size, Cover End:Flange Mount; Shaft End Pressure [Max:Left Hand (CCW); Port Type:3520VQ25A12-1AA20LH; Port Size:3; Mounting Flange:Flange; Pump Series:5/16 in; Max. RPM [Max:Standard Pilot; Relief Valve Setting:1.25 in; GPM @ 1,800 rpm, Cover End:Straight w/ Key; Pump Series:3520VQ; Shaft Length:2 1/2 in; Seal Material:Buna-N; Max. RPM [Max:2500; Minor Diameter:N/A; Mounting Flange:SAE C, 2 Bolt; Shaft Seal Type:Single Shaft Seal; Spline Description:N/A; Cover End RPM [Max:2500; Shaft End RPM [Max:2500; Controlled Flow Rate:N/A; Cover End Flow @ RPM:12 gal/min @ 1200 rpm, 18 gal/min @ 1800 rpm; Major Diameter [Max:N/A; Major Diameter [Min:N/A; Minor Diameter [Max:N/A; Minor Diameter [Min:N/A; Relief Valve Setting:N/A; Shaft End Flow @ RPM:25 gal/min @ 1200 rpm, 37.5 gal/min @ 1800 rpm; Manufacturer Part No.:3520VQ25A12-1AA20LH; Cover End Pressure [Max:2300; Shaft End Pressure [Max:3000; GPM @ 1,800 rpm, Cover End:18; GPM @ 1,800 rpm, Shaft End:37.5; Integral Valve Configuration:w/o Integral Valves; Port Orientation - Cover End:Outlet 135° CCW from Inlet; Port Orientation - Shaft End:Outlet Opposite Inlet; Pressure Port Size, Cover End:3/4 in Flange; Pressure Port Size, Shaft End:1 1/4 in Flange; Displacement Cover End (cu in/revolution):2.41; Displacement Shaft End (cu in/revolution):4.98;
Rexroth A4VSO180DR/30R-PPA13N00 Piston Pump	GPM @ 1,800 rpm, Cover End:75.0 LB; Shaft Key:Flange Mount; Minor Diameter:Left Hand (CCW); Shaft End Flow @ RPM:3520VQ25A12-1AA20LH; Shaft Type:3; Seal Material:Flange; Integral Valve Configuration:5/16 in; Pressure Port Size, Cover End:Standard Pilot; Mounting:1.25 in; Displacement Cover End (cu in/revolution):Straight w/ Key; Pump Series:3520VQ; Shaft Length:2 1/2 in; Seal Material:Buna-N; Max. RPM [Max:2500; Minor Diameter:N/A; Mounting Flange:SAE C, 2 Bolt; Shaft Seal Type:Single Shaft Seal; Spline Description:N/A; Cover End RPM [Max:2500; Shaft End RPM [Max:2500; Controlled Flow Rate:N/A; Cover End Flow @ RPM:12 gal/min @ 1200 rpm, 18 gal/min @ 1800 rpm; Major Diameter [Max:N/A; Major Diameter [Min:N/A; Minor Diameter [Max:N/A; Minor Diameter [Min:N/A; Relief Valve Setting:N/A; Shaft End Flow @ RPM:25 gal/min @ 1200 rpm, 37.5 gal/min @ 1800 rpm; Manufacturer Part No.:3520VQ25A12-1AA20LH; Cover End Pressure [Max:2300; Shaft End Pressure [Max:3000; GPM @ 1,800 rpm, Cover End:18; GPM @ 1,800 rpm, Shaft End:37.5; Integral Valve Configuration:w/o Integral Valves; Port Orientation - Cover End:Outlet 135° CCW from Inlet; Port Orientation - Shaft End:Outlet Opposite Inlet; Pressure Port Size, Cover End:3/4 in Flange; Pressure Port Size, Shaft End:1 1/4 in Flange; Displacement Cover End (cu in/revolution):2.41; Displacement Shaft End (cu in/revolution):4.98;

Axial piston pumps | Bosch Rexroth AG

Axial piston pumps in swash plate and bent axis design are intended for the medium and high pressure range. Numerous variations in the designs, performance

Rexroth Piston Pump - Buy and Check Prices Online for

Find here Rexroth Piston Pump dealers, retailers & distributors in India. Get latest details on Rexroth Piston Pump prices, models & wholesale prices and

Axial piston variable pump | Bosch Rexroth AG

Axial piston variable pump. A10VO series 5x. For machines with medium pressure requirements; Size 10 … 100; Nominal pressure 250 bar; Maximum pressure

Bosch Rexroth Hydraulic piston pumps - All the products on

Discover the hydraulic piston pump product range of Bosch Rexroth. Contact the manufacturer directly

AXIAL PISTON PUMP A10VSO SERIES 31 BOSCH REXROTH

Bosch Rexroth Axial Piston Variable Pumps are world recognized for their energy saving and compact sizes. Rexroth variable pumps move with the trend toward

Rexroth A10VSO71DR/31R-PPA12K01 Piston Pump Video

Contact Us

Vane Pump CO., LTD.: AddressTianqiao District, Jinan City, Shandong Province, China

Send Now

Rexroth A10VSO71DR/31R-PPA12K01 Technical Articles

Are hydraulic motors reversible?

are hydraulic motors reversible - ModestoHydraulic Motor Hydraulic Motors Other Piston Motor Reversible Motors Hydraulic Pump Danfoss Hydraulic Motor Intermopt Hydraulic Motor A2fm23 Close Loop How to Reverse a Hydraulic Motor--NINGBO...

How much horsepower do you need to run a hydraulic pump?

Horsepower Calculator - Metaris HydraulicsHowever, we cannot assume any responsibility for errors. *All trademarks are the property of their respective owners. Have a question or want to request a Log Splitter Hydraulic Pump Horsepower...

What happens when air gets into a hydraulic system?

How To Prevent Air In Your Hydraulic Oil? | Atlantic HydraulicMar 13, 2018 — Entrained air occurs most often as a result of air making it's way into a hydraulic system via the pump inlet. Leaks in suction lines or low reservoir ...