Danfoss G Frame Series 45 open circuit axial piston pump Service guide

PHASED

Series 45 Frame G

Open Circuit Axial

Piston Pumps

Service Manual

OUT

PRODUCT

Series 45 G Frame Open Circuit Axial Piston Pumps

Service Manual

Revisions

History of Revisions	Table of Revisions
	Date	Page	Changed	Rev.
PHASED		last	New Back Page	AB
	December 2010
	March 2003	-	First revision	-

OUT

PRODUCT

© 2010 Sauer-Danfoss.All rights reserved.

Sauer-Danfoss accepts no responsibility for possible errors in catalogs,brochures and other printed material.Sauer -Danfoss reserves the right to alter its products without prior notice.This also applies to products already ordered,provided that such alterations can be made without affecting agreed specifications.All trademarks in this material are properties of their respective owners.Sauer-Danfoss,the Sauer-Danfoss logotype, the Sauer-Danfoss S-icon,PLUS+1™,What really matters is inside® and Know-How in Motion™ are trademarks of the Sauer-Danfoss Group.

2	520L0605 • Rev AB • December 2010

Series 45 G Frame Open Circuit Axial Piston Pumps

Service Manual

Introduction	Overview............................................................................................................................................................	5
	Safety precautions..........................................................................................................................................	5
PHASED
	Unintended machine movement........................................................................................................	5
	Flammable cleaning solvents...............................................................................................................	5
	Fluid under pressure................................................................................................................................	5
	Personal safety............................................................................................................................................	5
	Symbols used in Sauer-Danfoss literature.............................................................................................	6
	General description........................................................................................................................................	7
	System circuit...................................................................................................................................................	8
Technical	General specifications...................................................................................................................................	9
specifications	Type of mounting......................................................................................................................................	9
	Auxiliary mounting pad options..........................................................................................................	9
	Control options..........................................................................................................................................	9
	Port options.................................................................................................................................................	9
	Direction of rotation.................................................................................................................................	9
	Installation position..................................................................................................................................	9
	Technical specifications..........................................................................................................................	9
	General specifications (continued).........................................................................................................	10
	OUTHydraulic parameters..................................................................................................................................	10
	Inlet pressure............................................................................................................................................	10
	Pressure compensator valve setting.................................................................................................	10
	Case pressure............................................................................................................................................	10
	Hydraulic fluid ..........................................................................................................................................	10
	Hydraulic parameters (continued)..........................................................................................................	11
	Temperature range.................................................................................................................................	11
	Fluid viscosity............................................................................................................................................	11
	Filtration .....................................................................................................................................................	11
Features	Displacement limiter...................................................................................................................................	12
	Auxiliary mounting pads............................................................................................................................	12
	Input shafts.....................................................................................................................................................	12
	Control options..............................................................................................................................................	13
	Operation...................................................................................................................................................	13
	Control options..............................................................................................................................................	14
	PRODUCT
Pressure	Required tools................................................................................................................................................	15
measurement	Port locations and gauge installation....................................................................................................	15
Initial start-up	General.............................................................................................................................................................	16
procedures	Start-up procedure.......................................................................................................................................	16
Fluid and filter	Recommendations.......................................................................................................................................	17
maintenance

520L0605 • Rev AB • December 2010

3

Series 45 G Frame Open Circuit Axial Piston Pumps

Service Manual

Troubleshooting	Excessive noise and / or vibration...........................................................................................................	18
	ctuator response is sluggish..................................................................................................................	18
PHASED
	ystem operating hot..................................................................................................................................	19
	Low pump output flow...............................................................................................................................	19
	Pressure or flow instability.........................................................................................................................	19
	Pressure or flow instability (continued)................................................................................................	20
	ystem pressure not reaching PC setting............................................................................................	20
	High inlet vacuum........................................................................................................................................	20
Adjustments	PC control........................................................................................................................................................	21
	LS control.........................................................................................................................................................	22
Minor repair	Shaft seal replacement...............................................................................................................................	23
	Removal......................................................................................................................................................	23
	Installation.................................................................................................................................................	23
	Auxiliary pads.................................................................................................................................................	24
	Removal......................................................................................................................................................	24
	Installation.................................................................................................................................................	24
	ControlOUT..............................................................................................................................................................	25
	Disassembly...............................................................................................................................................	25
	Inspection..................................................................................................................................................	25
	Control (continued)......................................................................................................................................	26
	Reassembly................................................................................................................................................	26
	Plug and fitting sizes and torques..........................................................................................................	27

PRODUCT

4	520L0605 • Rev AB • December 2010

	Series 45 G Frame Open Circuit Axial Piston Pumps
	Service Manual
	Introduction
Overview	This manual includes information for the installation,maintenance,and minor repair of
	the Series 45 frame G open circuit axial piston pumps.The manual includes a description
PHASED

of the units and their individual components,troubleshooting information,and minor repair procedures.Performing installation,maintenance,and minor repair of Series 45 G Frame axial piston pumps according to the procedures in this manual will not affect your warranty.

Performing minor repairs requires the unit to be removed from the vehicle/machine. Thoroughly clean the unit before beginning maintenance,or repair activities.Since dirt and contamination are the greatest enemies of any type of hydraulic equipment,follow cleanliness requirements strictly.This is especially important when changing the system filter and when removing hoses or plumbing.

		A worldwide network of Sauer-Danfoss Authorized Service Centers (ASCs) is available
	for major repairs.Major repairs require the removal of the unit’s endcap,which voids
	the warranty unless done by an ASC.Sauer-Danfoss ASCs are trained by the factory and
	certified on a regular basis.You can locate your nearest ASC using the distributor locator
	at www.sauer-danfoss.com
Safety precautions		Always consider safety precautions before beginning a service procedure.Protect
	OUTyourself and others from injury. ake these general precautions whenever servicing a
		hydraulic system.
		Unintended machine movement
		Warning
		Unintended movement of the machine or mechanism may cause injury to the technician
		or bystanders. To protect against unintended movement,secure the machine or
		disable / disconnect the mechanism while servicing.
		Flammable cleaning solvents
		Warning
		Some cleaning solvents are flammable.To avoid possible fire,do not use cleaning
		solvents in an area where a source of ignition may be present.
		Fluid under pressure
		Warning
		Escaping hydraulic fluid under pressure can have sufficient force to penetrate your skin
		causing serious injury and/or infection.This fluid may also be hot enough to cause burns.
		Use caution when dealing with hydraulic fluid under pressure.Relieve pressure in the
		system before removing hoses,fittings,gauges,or components.Never use your hand
		PRODUCT
		or any other body part to check for leaks in a pressurized line.Seek medical attention
		immediately if you are cut by hydraulic fluid.
		Personal safety
		Warning
		Protect yourself from injury.Use proper safety equipment,including safety glasses,at all
		times.

520L0605 • Rev AB • December 2010

5

	Series 45 G Frame Open Circuit Axial Piston Pumps
	Service Manual
	Introduction
Symbols used in	These symbols are in the illustrations and text of this manual. They communicate helpful
Sauer-Danfoss	information at the point where it is most useful to the reader.
PHASED
literature
	In most instances,the appearance of the symbol itself denotes its meaning. The legend
	below defines the symbol and explains its purpose.
	WARNING may result in injury	Tip,helpful suggestion
	CAUTION may result in damage to	Lubricate with hydraulic fluid
	product or property	Apply grease / petroleum jelly
	Reusable part
		Apply locking compound
	Non-reusable part,use a new part
		Inspect for wear or damage
	Non-removable item
		Clean area or part
	Option – either part may exist
		Be careful not to scratch or damage
	Superseded – parts are not
	OUTinterchangeable Note correct orientation
	Measurement required	Mark orientation for reinstallation
	Flatness specification	Torque specification
	Parallelism specification	Press in – press fit
	External hex head	Pull out with tool – press fit
	Internal hex head	Cover splines with installation
	Torx head	sleeve
		Pressure measurement / gauge
	O-ring boss port
		location or specification
	PRODUCT

6	520L0605 • Rev AB • December 2010

	Series 45 G Frame Open Circuit Axial Piston Pumps
	Service Manual
	Introduction
General description	Sauer-Danfoss Series 45 G Frame open circuit piston pumps convert input torque into
	hydraulic power.Rotational force is transmitted through the input shaft to the cylinder
PHASED
	block.The input shaft is supported by tapered roller bearings at the front and rear of
	the pump and is splined into the cylinder block .A lip-seal at the front end of the pump
	prevents leakage where the shaft exits the pump housing.The spinning cylinder block
	contains nine reciprocating pistons.Each piston has a brass slipper connected at one end
	by a ball joint.The slippers are held to the swashplate by the spring retainer and block
	spring.The block spring also holds the cylinder block to the valve plate.The reciprocating
	movement of the pistons occurs as the slippers slide against the inclined swashplate
	during rotation.One half of the cylinder block is connected to pump inlet and the other
	half to pump outlet,via the valve plate. As each piston cycles in and out of its bore,fluid
	is drawn from the inlet and displaced to the outlet thereby imparting power into the
	system circuit.A small amount of fluid is allowed to“leak”from the cylinder block / valve
	plate and slipper / swashplate interfaces for lubrication and cooling.Case drain ports are
	provided to return this fluid to the reservoir.
	The volume of fluid displaced into the system circuit is controlled by the angle of the
	swashplate.The swashplate is forced into an inclined position (into stroke) by the bias
	piston and spring.The servo piston opposes the action of the bias piston and spring
	forcing the swashplate out of stroke when hydraulic pressure in the control circuit rises
OUTabove the spring force.

The pump control,by varying the pressure at the servo piston,controls the displacement of fluid in the system circuit. Controls designed for Pressure Compensation (PC) or Load Sensing (LS) are available.For a detailed description of control operation,refer to

Control options, operation,page 13.

Pump and control sectional view

LS control

(attached to endcap)

LS spool

PC spool

LS adjustment

PC adjustment

	Displacement piston
	Swashplate
PRODUCT
Cylinder	Slipper retainer
block

		Tapered roller
		bearing
	Valve	Shaft seal
	plate

Cylinder block spring

Tapered

roller Input shaft bearing

Slipper

Piston

Bias piston

Bias spring

Bias piston guide

P104 002E

520L0605 • Rev AB • December 2010

7

	Series 45 G Frame Open Circuit Axial Piston Pumps
	Service Manual
	Introduction
System circuit	The pump receives fluid directly from the reservoir through the inlet line.A screen
	placed in the inlet protects the pump from large contaminants.The output of the pump
PHASED

is directed to a PVG-32 multi-section load sensing directional control valve which directs fluid to the actuators in the system.Fluid returning from the system is cooled by a heat exchanger and cleaned by a filter before returning to the reservoir.

The speed of the actuators in the system depends on the volume of fluid being provided by the pump.The operating pressure varies depending on actuator load,but is limited to an adjustable maximum setting by the PC section of the pump control and by a system relief valve integrated into the side module of the PVG valve.

The position of the PVG valve sets the demand for flow in the system and communicates this to the pump control by means of a hydraulic signal (load sense signal).The pump will provide as much flow to the system as it demands1 while limiting the maximum pressure. Therefore flow and pressure in the system are compensated to meet requirements.

Pictorial circuit diagram

P106 067E

8

Double-

OUT

tional motor

PRODUCT System pressure Servo pressure

Actuator pressure

Load sense pressure

Actuator return

Suction / case drain / system return

1 Full available flow is a function of pump displacement,operating speed,and efficiency.Refer to Series 45 Axial Piston Open Circuit Pumps Technical Information, 520L0519 for details.

520L0605 • Rev AB • December 2010

		Series 45 G Frame Open Circuit Axial Piston Pumps
		Service Manual
		Technical specifications
General		Type of mounting
specifications		SAE-C mounting flange.
PHASED
		Auxiliary mounting pad options
		SAE-A,SAE-B,SAE-B-B,SAE-C,SAE C-C
		Control options
		PC: Pressure Compensator
		LS: Load Sensing (with PC)
		Port options
		Inlet and system ports: SAE flanged ports,code 61 Inlet Code 62 outlet.
				Axial (end) ports or radial (side) ports.
		All other ports:		SAE straight thread O-ring boss.
		Direction of rotation
		Clockwise or counterclockwise.
		Installation position
	OUTInstallation position is discretionary.To satisfy inlet pressure conditions,it is
		recommended that the pump always be located below the lowest level of hydraulic fluid
		in the reservoir. The housing must always be filled with hydraulic fluid.
		Technical specifications
		Features and options						Model
		Feature				Unit		G74B		G90C
		Maximum Displacement				cm³ [in³]		74 [4.52]		90 [5.49]
		Flow at rated speed (theoretical)				l/min		177.6		198
						[US gal/min]		[46.9]		[52.3]
		Input torque at maximum displacement				N•m/bar		1.178		1.432
		(theoretical)				[lbf•in/1000 psi]		[719]		[874]
		Mass moment of inertia of internal				kg•m²		0.00630		0.00650
		rotating components				[slug•ft²]		[0.00465]		[0.00480]
		Weight		Axial ports		kg [lb]		29 [63]
				Radial ports				36 [80]
		PRODUCT
		Rotation						Clockwise,Counterclockwise
		Mounting						SAE-
		Auxiliary mounting						SAE-A,SAE-B,SAE-BB,SAE-C
		System ports (type)						4-bolt split flange
		System ports (location)						Axial,Radial
		Control types						PC,Remote PC,LS,LS with internal bleed
		Shafts				Splined		14 tooth,17 tooth
						Straight		Ø 31.75 mm [1.25 in]
		Displacement limiters						Optional,adjustable

520L0605 • Rev AB • December 2010

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