pvg pumps. pvg pumps currently 5 displacements 048 ml/rev (2.93 in ) 065 ml/rev (3.94 in) 075...

PVG PUMPS

PVG Pumps

• Currently 5 Displacements – 048 ml/rev (2.93 in³)– 065 ml/rev (3.94 in³) – 075 ml/rev (4.60 in³)– 100 ml/rev (6.00 in³)– 130 ml/rev (7.94 in³)

• 2 Frame Sizes– SAE “B” and “C”

• B Frame has a combination 2 or 4 bolt mount• C Frame only available with 2 bolt mount

PVG Pumps

• Continuous Operating Pressures– from 3,750 to 5000 psi, (depending on

displacement)

• Operating Speeds– from 600 to 2,700 rpm (depending on

displacement)

PVG Features

• Large Sealed Outboard Shaft Bearing – Enables easy maintenance of shaft, bearing, and shaft seal.– Allows for quick conversions, ie; keyed to splined– Allows for operation on special fluids– Capable of being belt driven

• Cylinder Barrel is Supported by a Hydrodynamic Bearing– Allows operation special fluids– Provides for an Infinite Bearing Life– Provides a compact design

PVG Features

• SAE - “Keyed” or “Splined Shafts”– S = Splined “B-B” or “C-C”– K = Splined “B” or “C”– Y = Long Keyed – Z = Short Keyed

• Special Polymerous Saddle Bearings– Allows operation on special fluids– Permits constant control reaction– Eliminates troublesome trunion bearing and covers– Provides long life

PVG Features

• Steel Piston Shoes with specially treated faces– Increased fluid retention– High pressure operation with longer life– High degree of contamination resistance

• ISO Classification 21/19/16– Allows for operation on special fluids

• Patented Pressure Lubricated Swashblock– Provides constant lubrication to swashblock bearings for high

pressure, high cycle applications

PVG Features

• Hard on Hard Running Surfaces– All running surfaces hardened to a Rockwell “C” of 60 - 65– Provides greater contamination resistance because surfaces

are file hard– Provides longer life– Allows operation on special fluids

• Quiet Valve Plate Design (Standard)– 80 - 85 dBA (depending on pump size, rpm, and pressure)

PVG Features

• 3 Valve Plate Styles– Rear Ported– Side Ported (top and bottom) non thru shaft– Side Ported (top and bottom) thru shaft

• Close Coupled Dual Pump Mounting– B frame to “AA”, or “A”, or “B”– C frame to “AA”, “A”, “B”, or “C”

PVG Features

• 4-way Parallel Style Compensator– Very fast compensator response. 45-55 milliseconds– The control is ported to enable tailoring of the control response to

the system– Hardened running surfaces

PVG SPECIFICATIONS

48 2.93 in³/rev (48,0 ml/rev) 5000 5800 270065 3.97 in³/rev (65 ml/rev) 5000 5800 270075 4.60 in³/rev (75,4 ml/rev) 3750 4250 2700100 6.00 in³/rev (98,3 ml/rev) 5000 5800 2400130 7.94 in³/rev (130,2 ml/rev 3750 4250 2400

Maximum Speed

Unit Size

Theoretical Maximum Displacement in³/rev (ml/rev)

Rated Continuous Pressure

Maximum Pressure

PVG 048 Performance Curves

PVG 048 Noise Curves

PVG 048 Inlet Curves

Driveshaft

Shaft Bearing

Shaft Seal

Saddle Bearings

Swash Block

Hydrodynamic Bearing Cylinder BarrelShoe Retainer Quiet Valve Plate

Fulcrum Ball & Spring Piston & Shoe Assembly

PVG Do’s and Don’ts

• The Do List– Fill the pump case prior to starting– Check alignment (.005 TIR)– Verify rotation– Connect drain line directly back to tank with no restrictions,

full sized and separately– Use a fast acting spike relief valve– Back off pressure compensator and relief valve prior to initial

start-up


• The Dreaded Don’t List or the “If you do it we won’t warranty it list”

– Do not restrict the case drain line• No filters (if you absolutely “gotta” have one, please install a

5 psi check valve in parallel with the filter)

• No in-line (Hedland style) flow meters, once again, (if you absolutely “gotta” have one, please install a full flow ball valve in parallel with the flow meter, and keep the ball valve open when not testing case leakage)

• No heat exchangers


• Do not restrict the case drain line continued– No other return or drain lines. If you have two

pumps there should be two case drain lines run separately back to tank.

– No inlet strainers or filters• Can cause cavitation. Especially true as temperature and

viscosity changes.

The Effects of Case Restriction

• Can cause piston shoes to lift off the swashblock– Maximum case differential pressure varies depending on rpm, it

can be a high as 60 psi for a PVG at 1800 rpm.• Vickers - 7 psi• Rexroth - 7 psi• Parker (PVP) - 5 psi• Denison (P6&7) - 25 psi• Oilgear (PVWH) - 10 psi

– Shoe lift off will cause the shoes to roll, cold work the ball and socket area of the shoe causing the shoe skirt to fail. This will in a short period of time cause a catastrophic pump failure. NO WARRANTY!

Case Pressure Below Maximum Differential

Piston Shoe Runs Flat on Swashblock

The Effects of Case Restriction

• Shoe Lift Off Can Also Cause– Breakthrough of the hardening on the swashblock

• causing extensive wear on the swashblock and shoe, as well as contaminating the reservoir and system.

– Shaft seal leakage• Maximum shaft seal pressure is 25 psi

NOTE; Gap Between Shoe and Swashblock

Case Pressure Above Maximum Differential


• Improper Shaft Alignment– Can cause the pump not to build pressure, creates

abnormal wear on the valve plate, hydrodynamic bearing, and cylinder barrel

NOTE: Cylinder Barrel not parallel to valve plate

Side load

PVG Controls

• Pressure Controls– P-1NN Single Pressure Compensator– P-2** Dual Pressure Compensator– P-C** Soft Start Compensator – P-1NN/F Pressure Comp w/ Load Sensing– P-1NN/H Pressure Comp w Horsepower

Limiting (c-frame units only)

– P-1NN/G P Comp, LS, HP Limiting

PVG Controls

• Volume Controls– V-M20 Servo with electronic feedback

– R Solenoid operated two position pump control

P-1NN Compensator

P-1NN/F Load Sense Control

Load Sense Module

OP-4

OP-34-way Spool

OP-2

OP-5

Load Sense Spool

Load Sense Line

Bias Spring

Control Piston

OP-6 OP-1

Compensator Poppet

Compensator Adjustment

ScrewLS Delta P Spring

LS Adjustment Screw

Flow Restriction

OP-9

OP-14

Load Sense - Low Pressure Stand-byLoad Sense - Low Pressure Stand-by

Full Stroke Condition

Load Sensing - Dynamic Condition

Compensated - Static Condition

2 Speed Motor Circuit - Fixed Volume

34 GPM

15 GPM

1500 PSI Working Pressure

3000 PSI

34 GPM

HP Required @ 34 GPM = 35.01

HP Required @ 15 GPM = 70.01

Why is the horsepower double @ 15 GPM?

Variable Volume - Pressure Compensated

34 GPM

15 GPM3200 PSI

3000 PSI

HP Required @ 34 GPM = 35.01 HP


HP Savings @ 15 GPM = 39.12 HP

1500 psi Working Pressure

Variable Volume - Load Sensed

34 GPM

15 GPM3200 psi

Delta P 170

3000 PSI

1500 psi Working Pressure

1670 PSI



HP Savings L.S. vs. Fixed = 52.10 HP

HP Savings L.S. vs.. P Comp = 12.98 HP

P-1NN/F Load Sense Plus

A

1B

GPAOP5 OP7

OP1 OP2

OP6

OP3 OP4

OP8RP1

1A

OP14

LS

OP9

Load Sense Plus - Stand-by

Delta P Adjustment

Stand-by Adjustment

Compensator Adjustment

Load Sense + Dynamic

Condition

Set 400 psi

Set 170 psi

1570 psiIf the working pressure is

1400 psi1400 psi

P-2NN Dual Pressure Compensator

Low Pressure Adjustment

Solenoid Selector

High Pressure Adjustment

OP-1

Low Pressure Poppet

OP-4OP-3

OP-2 4-way Compensator Spool

High Pressure Poppet

OP-14 OP-5 OP-6

Bias Spring

OP-10

P-2NN Compensator - Full Stroke

P-2NN Compensator - Low Pressure

P-2NN Compensator - High Pressure

P-CXX Soft Start Control

P-CXX Soft Start Control Full Stroke - High Pressure

Unloading Solenoid Valve

P-CXX - Soft Start Control Unloaded

Unloading Solenoid

Valve - Energized

P-CXX Soft Start Control Compensated High Pressure

Unloading Solenoid Valve - De-energized

The End

Thank you for buying Oilgear Products

pvg pumps. pvg pumps currently 5 displacements 048 ml/rev (2.93 in ) 065 ml/rev (3.94 in) 075...

Documents