Service Manual
Open Circuit Axial Piston Pumps
Series 45 E Frame
powersolutions.danfoss.com
Service Manual
Series 45 E Frame Open Circuit Pumps
Revision history |
Table of revisions |
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Changed |
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September 2016 |
Replaced the ETL schematic |
0401 |
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August 2016 |
Added displacement limiter adjustments |
0301 |
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August 2015 |
Danfoss Layout |
0300 |
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October 2012 |
add new control types |
AG |
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November 2010 |
new last page |
AE |
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February 2010 |
fix Osaka address |
AD |
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March 2008 |
add displacement limiter specs |
AC |
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March 2005 |
First edition |
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2 | © Danfoss | September 2016 |
AX00000024en-US0401 |
Service Manual |
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Series 45 E Frame Open Circuit Pumps |
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Contents |
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Introduction |
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Overview.............................................................................................................................................................................................. |
5 |
Safety precautions............................................................................................................................................................................ |
5 |
Unintended machine movement.......................................................................................................................................... |
5 |
Flammable cleaning solvents................................................................................................................................................. |
5 |
Fluid under pressure.................................................................................................................................................................. |
5 |
Personal safety............................................................................................................................................................................. |
5 |
Symbols used in Danfoss literature............................................................................................................................................ |
6 |
General description......................................................................................................................................................................... |
7 |
System circuit..................................................................................................................................................................................... |
8 |
Technical specifications |
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General specifications..................................................................................................................................................................... |
9 |
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 |
Hydraulic parameters................................................................................................................................................................... |
11 |
Inlet pressure.............................................................................................................................................................................. |
11 |
Pressure compensator valve setting.................................................................................................................................. |
11 |
Case pressure............................................................................................................................................................................. |
11 |
Hydraulic fluid ........................................................................................................................................................................... |
11 |
Temperature range (1)............................................................................................................................................................. |
11 |
Fluid viscosity............................................................................................................................................................................. |
11 |
Filtration ...................................................................................................................................................................................... |
11 |
Features |
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Displacement limiter..................................................................................................................................................................... |
12 |
Auxiliary mounting pads............................................................................................................................................................. |
12 |
Input shafts....................................................................................................................................................................................... |
13 |
Control options............................................................................................................................................................................... |
13 |
General......................................................................................................................................................................................... |
13 |
PC control.................................................................................................................................................................................... |
13 |
LS control..................................................................................................................................................................................... |
14 |
Electric Proportional Controls.............................................................................................................................................. |
15 |
Electric On/Off Controls.......................................................................................................................................................... |
15 |
Electronic Torque Limiting Controls (ETL)....................................................................................................................... |
16 |
PLUS+1® Compliance......................................................................................................................................................... |
16 |
Electric Torque Limiting Control Principle................................................................................................................. |
16 |
Pressure measurement |
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Required tools................................................................................................................................................................................. |
18 |
Port locations and gauge installation..................................................................................................................................... |
18 |
Initial Start-Up Procedures |
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General............................................................................................................................................................................................... |
19 |
Start-up procedure........................................................................................................................................................................ |
19 |
Fluid and Filter Maintenance |
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Recommendations........................................................................................................................................................................ |
20 |
Troubleshooting |
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Excessive noise and/or vibration.............................................................................................................................................. |
21 |
Actuator response is sluggish.................................................................................................................................................... |
21 |
System operating hot................................................................................................................................................................... |
21 |
Low pump output flow................................................................................................................................................................ |
22 |
Pressure or flow instability.......................................................................................................................................................... |
22 |
System pressure not reaching PC setting............................................................................................................................. |
23 |
High inlet vacuum.......................................................................................................................................................................... |
23 |
© Danfoss | September 2016 |
AX00000024en-US0401 | 3 |
Service Manual |
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Series 45 E Frame Open Circuit Pumps |
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Contents |
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Adjustments |
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PC control.......................................................................................................................................................................................... |
24 |
LS control.......................................................................................................................................................................................... |
26 |
Displacement Limiters................................................................................................................................................................. |
27 |
Minor repair |
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Shaft seal replacement................................................................................................................................................................. |
29 |
Removal........................................................................................................................................................................................ |
29 |
Installation................................................................................................................................................................................... |
29 |
Auxiliary pads.................................................................................................................................................................................. |
30 |
Removal........................................................................................................................................................................................ |
30 |
Installation................................................................................................................................................................................... |
30 |
LS and PC Controls......................................................................................................................................................................... |
30 |
Disassembly................................................................................................................................................................................ |
30 |
Inspection.................................................................................................................................................................................... |
31 |
Reassembly................................................................................................................................................................................. |
32 |
Electric Controls.............................................................................................................................................................................. |
34 |
Disassembly................................................................................................................................................................................ |
34 |
Inspection.................................................................................................................................................................................... |
34 |
Reassembly................................................................................................................................................................................. |
35 |
Electronic Torque Limiting Control......................................................................................................................................... |
36 |
Repair............................................................................................................................................................................................ |
36 |
Angle Sensor.................................................................................................................................................................................... |
37 |
Removal........................................................................................................................................................................................ |
37 |
Inspection.................................................................................................................................................................................... |
37 |
Reassembly................................................................................................................................................................................. |
38 |
Servo Control Orifice..................................................................................................................................................................... |
39 |
Plug and fitting sizes and torques........................................................................................................................................... |
40 |
4 | © Danfoss | September 2016 |
AX00000024en-US0401 |
Service Manual
Series 45 E Frame Open Circuit Pumps
This manual includes information for the installation, maintenance, and minor repair of the Series 45 frame E open circuit axial piston pumps. The manual includes a description of the units and their individual components, troubleshooting information, and minor repair procedures. Performing installation, maintenance, and minor repair of Series 45 E 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 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. 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.powersolutions.danfoss.com
Always consider safety precautions before beginning a service procedure. Protect yourself and others from injury. Take these general precautions whenever servicing a hydraulic system.
W 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.
W 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.
W 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 or any other body part to check for leaks in a pressurized line. Seek medical attention immediately if you are cut by hydraulic fluid.
W Warning
Protect yourself from injury. Use proper safety equipment, including safety glasses, at all times.
© Danfoss | September 2016 |
AX00000024en-US0401 | 5 |
Service Manual
Series 45 E Frame Open Circuit Pumps
Introduction
WARNING may result in injury
CAUTION may result in damage to product or property
Reusable part
Non-reusable part, use a new part
Non-removable item
Option - either part may exist
Superseded - parts are not interchangeable Measurement required
Flatness specification
Parallelism specification
External hex head
Internal hex head
Torx head
O-ring boss port
Tip, helpful suggestion
Lubricate with hydraulic fluid
Apply grease / petroleum jelly
Apply locking compound
Inspect for wear or damage
Clean area or part
Be careful not to scratch or damage Note correct orientation
Mark orientation for reinstallation Torque specification
Press in - press fit
Pull out with tool – press fit
Cover splines with installation sleeve
Pressure measurement/gauge location or specification
The symbols above appear in the illustrations and text of this manual. They are intended to communicate helpful information at the point where it is most useful to the reader. In most instances, the appearance of the symbol itself denotes its meaning. The legend above defines each symbol and explains its purpose.
6 | © Danfoss | September 2016 |
AX00000024en-US0401 |
Service Manual
Series 45 E Frame Open Circuit Pumps
Introduction
Danfoss Series 45 E frame open circuit piston pumps convert input torque into hydraulic power. Rotational force is transmitted through the input shaft to the cylinder 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 lipseal 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. Via the valve plate, one half of the cylinder block is connected to pump inlet and the other half to pump outlet. 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 above 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 on page 13.
Pump and control sectional view
LS control
(attached to endcap)
LS spool |
PC spool |
LS adjustment |
PC adjustment |
Lifting lug |
Servo piston guide |
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Adjustable |
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Servo piston |
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displacement |
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Slipper retainer |
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limiter |
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Valve plate |
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Shaft seal |
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Cylinder block |
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Input shaft |
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Block |
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spring |
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Tapered |
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Tapered |
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roller |
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roller |
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bearing |
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bearing |
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Swashplate |
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Slipper |
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Bias spring |
Bias piston |
Piston |
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Bias piston guide |
P104001E |
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© Danfoss | September 2016 |
AX00000024en-US0401 | 7 |
Service Manual
Series 45 E Frame Open Circuit Pumps
Introduction
Pictorial circuit diagram
Reservoir
P104 045E
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 is directed to a PVG-32 multisection 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 demands while limiting the maximum pressure. Therefore flow and pressure in the system are compensated to meet requirements.
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.
Double-acting cylinder
PVG 32 multi-section load sensing
control
valve
Heat exchanger
Filter
Bi-directional gear motor
System pressure
Servo pressure
Actuator pressure
Load sense pressure
Actuator return
Suction / case drain / system return
8 | © Danfoss | September 2016 |
AX00000024en-US0401 |
Service Manual
Series 45 E Frame Open Circuit Pumps
SAE-C mounting flange.
SAE-A, SAE-B, SAE-B-B, SAE-C, SAE C-C
PC: Pressure Compensator
LS: Load Sensing (with PC)
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.
Clockwise or counterclockwise.
Installation 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.
Features and options
Feature |
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Unit |
Model |
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E100B |
E130B |
E147C |
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Maximum Displacement |
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cm³ [in³] |
100 [6.10] |
130 [7.93] |
147 [8.97] |
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Flow at rated speed (theoretical) |
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l/min |
245 |
286 |
309 |
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[US gal/min] |
[64.7] |
[75.6] |
[81.6] |
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Input torque at maximum displacement (theoretical) |
N•m/bar |
1.592 |
2.069 |
2.340 |
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[lbf•in/1000 psi] |
[972] |
[1263] |
[1428] |
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Mass moment of inertia of internal rotating |
kg•m² |
0.0128 |
0.0128 |
0.0128 |
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components |
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[slug•ft²] |
[0.0094] |
[0.0094] |
[0.0094] |
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Weight |
Axial ports |
kg [lb] |
51.3 [113] |
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Radial ports |
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54.9 [121] |
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Rotation |
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Clockwise, Counterclockwise |
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Mounting |
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SAE-C |
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Auxiliary mounting |
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SAE-A, SAE-B, SAE-BB, SAE-C, SAE-CC |
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System ports (type) |
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4-bolt split flange |
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System ports (location) |
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Axial, Radial |
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Control types |
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PC, Remote PC, LS, LS with internal bleed |
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© Danfoss | September 2016 |
AX00000024en-US0401 | 9 |
Service Manual
Series 45 E Frame Open Circuit Pumps
Technical specifications
Features and options (continued)
Feature |
Unit |
Model |
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E100B |
E130B |
E147C |
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Shafts |
Splined |
13-tooth, 14-tooth, 17-tooth |
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Straight |
Ø 38.08 mm [1.5 in] |
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Displacement limiters |
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Optional, adjustable |
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Ratings
Rating |
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Units |
Model |
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E100B |
E130B |
E147C |
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Input speed¹ |
minimum |
min-1 (rpm) |
500 |
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500 |
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500 |
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continuous |
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2450 |
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2200 |
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2100 |
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maximum |
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2880 |
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2600 |
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2475 |
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Working pressure |
continuous |
bar [psi] |
310 [4495] |
310 [4495] |
260 [3770] |
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maximum |
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400 [5800] |
400 [5800] |
350 [5075] |
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External shaft loads |
External moment (Me) |
N•m [lbf•in] |
455 [4030] |
360 [3190] |
396 [3500] |
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Thrust in (Tin), out (Tout) |
N [lbf] |
2846 |
[640] |
1735 |
[390] |
2113 |
[475] |
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Thrust out (Tout) |
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7740 |
[1740] |
6672 |
[1500] |
7117 |
[1600] |
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Bearing life |
at 140 bar [2030 psi] |
B10 hours |
77 200 |
32 700 |
21 600 |
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at 210 bar [3045 psi] |
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19 800 |
8400 |
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5500 |
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at 260 bar [3770 psi] |
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9700 |
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4116 |
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2700 |
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at 310 bar [4495 psi] |
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5400 |
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2300 |
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— |
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Mounting flange load |
Vibratory (continuous) |
N•m [lbf•in] |
1920 |
[17 000] |
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moments |
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Shock (max) |
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6779 |
[60 000] |
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(1) Input speeds are valid at 1 bar absolute [0 in Hg vac] inlet pressure. See Inlet pressure vs. speed charts in the Series 45 Technical Information Manual 520L0519.
10 | © Danfoss | September 2016 |
AX00000024en-US0401 |
Service Manual
Series 45 E Frame Open Circuit Pumps
Technical specifications
Minimum pressure, continuous = 0.8 bar absolute [6.7 inch Hg vac] (at reduced maximum pump speed) Minimum pressure, cold start = 0.5 bar absolute [15.1 inch Hg vac]
Setting |
100 and 130 cc |
147 cc |
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Minimum |
100 bar [1450 psi] |
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Maximum |
310 bar [4495 psi] |
260 bar [3770 psi] |
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Maximum continuous: 0.5 bar [7 psi] Above inlet
Intermittent: 2 bar [29 psi] Cold start
Refer to Danfoss publication Fluids and Filtration BLN-9887 or 520L0463. For information on biodegradable fluids refer to Biodegradable Hydraulic Fluids 520L0465. See Fluid and Filter Maintenance on page 20 for recommended fluid and filter change intervals.
Intermittent (cold start): - 40° C [- 40° F]
Continuous: 82° C [180° F]
Maximum (2): 104° C [220° F]
(1)Hydraulic fluid viscosity must be maintained within the prescribed limits.
(2)As measured at the hottest point in the system, e.g. drain line.
Viscosity limits
Rating |
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mm2/s (cSt) [SUS] |
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ν continuous |
minimum |
9 [58] |
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maximum |
110 [500] |
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ν intermittent |
minimum |
6.4 [47] |
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maximum (cold start) |
1000 [4700] |
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Required cleanliness level: ISO 4406 Class 18/13 or better. Refer to Danfoss publications Fluids and Filtration BLN-9887 or 520L0463 and Design Guidelines for Selecting and Maintaining the Required Hydraulic Fluid Cleanliness 520L0465. See Fluid and Filter Maintenance on page 20 for recommended fluid and filter change intervals.
© Danfoss | September 2016 |
AX00000024en-US0401 | 11 |
Service Manual
Series 45 E Frame Open Circuit Pumps
Frame E Series 45 pumps are available with an optional adjustable maximum displacement limiter. The adjustable stop limits the pump’s maximum displacement. The displacement change per turn of the displacement limiter adjustment screw is shown below.
Setting range
100 cc |
40 to 100 cm³ [2.44 to 6.1 in³] |
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130 cc |
70 to 130 cm³ [4.27 to 7.93 in³] |
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147 cc |
87 to 147 cm³ [5.31 to 8.97 in³] |
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Displacement change
100 cc |
8.4 cc/rev [0.513 in³/rev] |
130 cc
147 cc
Displacement limiter
P107 779E
Displacement change - older models
100 cc |
6.5 cc/rev [0.397 in³/rev] |
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130 cc |
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147 cc |
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Displacement limiter - older models
P104 046
Auxiliary mounting pads are available for all radial ported Series 45 pumps. These pads are typically used for mounting auxiliary hydraulic pumps.
Since the auxiliary pad operates under case pressure, you must use an O-ring to seal the auxiliary pump mounting flange to the pad. Oil from the main pump case lubricates the drive coupling. For details refer to Series 45 Axial Piston Open Circuit Pumps Technical Information 520L0519.
12 | © Danfoss | September 2016 |
AX00000024en-US0401 |
Service Manual
Series 45 E Frame Open Circuit Pumps
Features
Auxiliary pad options
P104 047
Series 45 E frame pumps are available with a variety of splined and straight keyed shafts. For information on shafts refer to Series 45 Axial Piston Open Circuit Pumps Technical Information 520L0519.
The Series 45 Frames E have three possible control options, a Load Sensing (LS) control with Pressure Compensator (PC), a PC only control, or an electric control.
The bias piston and spring (1) acts at all times to push the swashplate (2) to maximum angle causing the pump to stroke. The servo piston (3) acts against the bias piston and spring to reduce the swashplate angle causing the pump to destroke. Swashplate angle determines pump outlet flow. The pump control, depending on conditions in the system circuit, sets swashplate angle by metering system pressure to the servo piston.
Cross-section pump
3
1 |
2 |
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P104 048 |
Bias spring and servo piston set swashplate position
The PC control design maintains a constant pressure in the hydraulic circuit as flow varies. The PC control modulates pump flow accordingly to maintain system pressure at the PC setting as the PC adjusting plug
(4) and spring (5) defines.
When system pressure, acting on the non-spring end of the PC spool (6), overcomes the force of the PC spring, the spool shifts porting system pressure to the servo piston and the swashplate angle decreases. When system pressure drops below the PC setting, the PC spring shifts the spool in the opposite
© Danfoss | September 2016 |
AX00000024en-US0401 | 13 |
Service Manual
Series 45 E Frame Open Circuit Pumps
Features
direction connecting the servo piston to pump case and the swashplate angle increases. The swashplate is maintained at whatever angle is required to keep system pressure at the PC setting.
Cross-section PC control
4
6 |
5 |
P104 049
PC spool shifts to port system pressure to servo piston
The LS control design matches pump flow with system demand. The LS control senses the flow demand of the system as a pressure drop across the External Control Valve (ECV). As the ECV opens and closes, the pressure delta across the valve changes. When opening, the delta decreases. When closing, the delta increases. The LS control then increases or decreases pump flow to the system until the pressure delta becomes equal to the LS setting as defined by the LS adjusting plug (7) and spring (8).
The LS control consists of two spool valves that connect the servo piston either to pump case or system pressure. The PC spool (6) controls the pressure-compensating function of the control as previously described. The LS spool (9) controls the load-sensing function. The PC spool has priority over the LS spool.
Through internal porting, system pressure (upstream of ECV) is applied to the non-spring end of the LS spool, and through hydraulic line connected at port X, LS pressure (downstream of ECV) is applied to the spring end. This arrangement allows the LS spool to act on the delta between system pressure and LS pressure. The LS spring sets the threshold of operation (LS setting).
Because the swashplate is biased to maximum angle, the pump attempts to deliver full flow to the hydraulic system. When the flow being delivered exceeds demand, the pressure delta across the ECV is great enough to overcome spring force and shift the LS spool porting system pressure to the servo piston. The pump de-strokes reducing flow until the delta across the ECV becomes equal to the LS setting. When flow being delivered is less than demand, the delta across the ECV drops below the LS setting and the LS spring shifts the spool connecting the servo piston to pump case. The pump strokes increasing flow until the delta across the ECV becomes equal to the LS setting.
When the external control valve is placed in neutral, it connects the LS signal line to drain. With no LS pressure acting on the non-spring end of the LS spool, the pump adjusts stroke to whatever position necessary to maintain system pressure at the LS setting. The pump is now in standby mode.
Because of the series arrangement of the LS and PC spools, the PC spool will override the LS spool. If at any time system pressure reaches the PC setting, the PC spool will shift blocking the passage that connects the LS spool with the servo piston and porting system pressure to the servo piston causing the pump to destroke.
Typical load-sensing control valve
Load |
Return |
2pressure |
pressure |
|
Tank |
Load sense |
System |
|
pressure |
2pressure |
P101 665E |
14 | © Danfoss | September 2016 |
AX00000024en-US0401 |