Technical Information

Series 42 4T Axial Piston Tandem Pumps
Size 41/51

www.danfoss.com

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51

Revision history

2 | © Danfoss | May 2024

Table of revisions
Date

ChangedRev

May 2024

Updated shaft options

0306

April 2024

Minor correction to NFPH control

0305

April 2023

Layout adjustment

0304

March 2023

Corrected max pressure0303

November 2020

Minor update in Hydraulic Fluid Parameters

0302

July 2020

Changed document number from 'BC00000036' to 'BC152886482857'

0301

December 2018

Corrected technical data in System Parameters

0201

June 2016

converted to new layout

0101

May 2015

Converted to DITA CMSBAFebruary 2008

Corrections-Drawings

AB

January 2008

First editionAA

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Contents
General Description
Basic Design........................................................................................................................................................................................5
System Diagram................................................................................................................................................................................6
System Schematic............................................................................................................................................................................ 7
Technical Specifications
System Specifications..................................................................................................................................................................... 9
System Parameters.......................................................................................................................................................................... 9
Hydraulic Fluid Parameters........................................................................................................................................................ 10
Operating Parameters
System Requirements...................................................................................................................................................................11
System Parameters........................................................................................................................................................................11
Hydraulic Fluid Parameters........................................................................................................................................................ 12
Sizing Equations............................................................................................................................................................................. 13
System Design Parameters
Fluid and Filtration........................................................................................................................................................................ 14
Filtration Configuration............................................................................................................................................................... 14
Mounting Flange Loads...............................................................................................................................................................15
Estimating Overhung Load Moment.................................................................................................................................15
Case Drain.........................................................................................................................................................................................16
External Shaft Load and Bearing Life...................................................................................................................................... 16
Hydraulic Unit Life......................................................................................................................................................................... 17
Efficiency Graphs............................................................................................................................................................................18
Features and Options
Charge Pump...................................................................................................................................................................................19
Charge Pump Sizing Example:............................................................................................................................................. 19
Charge Relief Valve........................................................................................................................................................................19
Overpressure Protection............................................................................................................................................................. 20
Bypass Valve.....................................................................................................................................................................................21
Displacement Limiters................................................................................................................................................................. 21
Shaft Options...................................................................................................................................................................................21
Auxiliary Mounting Pads............................................................................................................................................................. 22
Center Coupling............................................................................................................................................................................. 23
Control Selection............................................................................................................................................................................23
Manual Displacement Control (MDC).....................................................................................................................................25
Features and Benefit of MDC................................................................................................................................................25
Control Input Signal.................................................................................................................................................................26
Response Time...........................................................................................................................................................................26
Control Handles.........................................................................................................................................................................27
Electric Solenoid Override to Neutral................................................................................................................................27
Emergency Override to Neutral with Port for Brake Pressure Release..................................................................28
Neutral Start Switch (NSS)..................................................................................................................................................... 29
NSS with Back-up Alarm (BUA) Switch..............................................................................................................................29
Connectors..................................................................................................................................................................................29
Non-feedback, proportional hydraulic control (NFPH).................................................................................................... 31
Features and Benefits of the NFPH control..................................................................................................................... 32
Connectors and Port locations............................................................................................................................................ 32
Installation Drawings
Manual Displacement Control (MDC).....................................................................................................................................33
Port Description........................................................................................................................................................................ 33
Dimensions................................................................................................................................................................................. 35
Non-Feedback, Proportional Hydraulic (NFPH).................................................................................................................. 38
Port Description........................................................................................................................................................................ 38
Dimensions................................................................................................................................................................................. 40
Shaft Options...................................................................................................................................................................................43
Displacement Limiter................................................................................................................................................................... 44
By-pass Valve................................................................................................................................................................................... 45© Danfoss | May 2024

BC152886482857en-000306 | 3

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Contents
Control Modules.............................................................................................................................................................................45
Auxiliary Mounting Pads............................................................................................................................................................. 47
Model CodeModel Code: A, Y, Z........................................................................................................................................................................49
Model Code: FD, FX, RD, RX........................................................................................................................................................50
Model Code: FE, RE........................................................................................................................................................................ 51
Model Code: FT, RT, FH, RH, FJ, RJ, FK, RK.............................................................................................................................. 52
Model Code: FL, RL, FM. RM........................................................................................................................................................53
Model Code: C, F, S........................................................................................................................................................................ 55
Model Code: U, G, V.......................................................................................................................................................................56
Model Code: N, P............................................................................................................................................................................ 57

4 | © Danfoss | May 2024

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
General Description

Basic Design
S42 Integrated Tandem Pumps (4T) are advanced hydrostatic units for medium power applications withmaximum loads of 415 Bar [6020 psi] (41 cm3) and 350 Bar [5075 psi] (51 cm3). You can combine thesepumps with a suitable Danfoss motor or other products in a system to transfer and control hydraulicpower.
The 4T axial piston pump is a compact, high power density unit, using the parallel axial piston/slipper
concept in conjunction with tiltable swashplates to vary the pumps’ displacements.
Reversing the angle of the swashplate reverses the flow of fluid from the pump, and reversing thedirection of rotation of the motor output. 4T axial piston pumps provide an infinitely variable speed
range between zero and maximum in both forward and reverse.
4T axial piston pumps use a cradle swashplate design with a hydraulic servo control cylinder. Control isprovided through a compact servo control system. Two types of servo controls are available. These
include mechanical hydraulic actuated feedback controls, and hydraulic proportional control. These
controls feature low hysteresis and responsive performance.
Cross-sectional view

PistonRoller bearing

Swashplate

Valve plate
Ball bearing
P400160© Danfoss | May 2024

BC152886482857en-000306 | 5

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
General Description
System Diagram

FilterCharge Pressure

Control Pressure

System Pressure

Low Loop Pressure

Charge Pump

SuctionScreenReservoir

Suction/Case Drain/
System Return

Bypass Check

Heat Exchanger

Control Handle
Servo Control
CylinderSwash Plate

Displacement
Control Spool

Charge Pressure
Relief Valve

Cylinder Block
Assembly
Input
Shaft

Valiable
Displacement
Pump

Brake release
control valve

Loop
Flushing
Valve
Gear box

6 | © Danfoss | May 2024

Motor

Motor displacement
control valve

P106 147E

Charge check/
HPRV valve

Loop
Flushing
Valve
Motor

Gear box

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
General Description
System Schematic
4T Axial Piston Pump

M6

L1

L2

Front

Rear

M5

M4

M4

M5

M2 B

Gearbox

Motor

M1 A

M6 C M1

D

M2

Motor

GearboxP400161

The illustration above shows a schematic of a 4T axial piston pump. System ports A, C and B, D connect tothe high pressure work lines. Return fluid is received from its inlet port and discharged through the outlet
port. Flow direction is determined by swashplate position. You can read system port pressure throughports M1 and M2. The pump has two case drains (L1 and L2) to ensure there is lubricating fluid in the© Danfoss | May 2024

BC152886482857en-000306 | 7

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
General Description
system. This schematic includes a manual displacement control. For other control schematics see therelated control section: Manual Displacement Control (MDC) on page 25, Non-feedback, proportional
hydraulic control (NFPH)

8 | © Danfoss | May 2024

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Technical Specifications

System Specifications
General Specifications
FeatureSeries 42 4T

Pump typeIn-line, axial piston, positive displacement pumps including cradle
swashplate and servo control

Direction of input rotation

Clockwise or counterclockwise

Recommended installation position

Pump installation recommended with control position on the top or
side. Consult Danfoss for non conformance guidelines. The housing
must always be filled with hydraulic fluid.

Other system requirements

Independent braking system, suitable reservoir and heat exchanger.

Hardware Features
Single variable pump

Pump configuration
Displacement

cm3
[in3]

Weightkgf[lbf]

Mass moment of inertia

kg•m2
0.0072 [0.0054][lbf•ft2]

Type of front mounting flange(SAE flange size per SAE J744)

51 [3.11] x 2

MDC: 76 [168]
NFPH: 72 [158]0.0076 [0.0056]

2 Bolt SAE C (4 additional bolt holes available)
SAE-twin ports, radial, opposite side ports

Port connections
System pressure regulation

40.9 [2.50] x 2

bar
[psi]

210-415 [3045-6020]

210-325 [3045-4715]

Displacement limiters

OptionInput shaft options

SplinedAuxiliary mounting pad(SAE pad per SAE J744)

SAE A (9 tooth, 11 tooth and 13 tooth)
SAE B (13 tooth)Control options

MDC, NFPH

Loop flushing

None

System Parameters
Case pressure
Continuous pressure

bar
[psi]

3 [44]

Maximum pressure (cold start)

bar
[psi]

10.3 [150]Displacement

cm3

41

51

Rated pressure

bar
[psi]

350 [5075]

325 [4713]

Maximum pressure

bar
[psi]

415 [6017]

350 [5075]

Pressure Limits© Danfoss | May 2024

BC152886482857en-000306 | 9

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Technical Specifications
Speed Limits
Frame size

cm3

41

Minimum speed

min-1
(rpm)

500

Rated speed at maximum
displacement

min-1
(rpm)

3200

2900

Maximum speed at maximum
displacement

min-1
(rpm)

3450

3400

51

Charge Pump Displacement and Setting Pressure
cm3

Frame size

cm3/rev

Internal-[in3/rev]

Charge relief
valve settings

Standard

bar
[psi]

Optional

41

51

none

none
20 [290]
14-24 [203-340]

Theoretical Flow
Frame size

cm3

41

51

Theoretical flow at rated speedl/min[US gal/min]

131 [34.6]

148 [39.1]

Check/high Pressure Relief ValveNo relief valve /check only

Relief valve / check—210-415 [3045-6020] or by setting available
210, 250, 280, 300, 325, 345, 360, 385, 415

Minimum-40 °C [-40 °F]

Intermittent, cold start

Maximum continuous

104 °C [220 °F]-

Maximum

115 °C [240 °F]

Intermittent

Options
Settingbar[psi]

Hydraulic Fluid Parameters
Fluid temperature range

Fluid cleanliness level
ISO 4406 Class 22/18/13

Required fluid cleanliness level

Fluid viscosity

10 | © Danfoss | May 2024

Minimum

7.0 mm2/s (cSt)Intermittent

Recommended operating range

12-60 mm2/s (cSt)-

Maximum

1600 mm2/s (cSt)Intermittent, cold start

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Operating Parameters

System Requirements
Independent braking system

W Warning
Unintended vehicle or machine movement hazard. The loss of hydrostatic drive line power, in any
mode of operation (forward, neutral, or reverse) may cause the system to lose hydrostatic braking
capacity. You must provide a braking system, redundant to the hydrostatic transmission, sufficient tostop and hold the vehicle or machine in the event of hydrostatic drive power loss.
Reservoir
Design the system to accommodate maximum volume changes during all system operating modes andto promote de-aeration of the fluid as it passes through the tank. Minimum reservoir volume is 5/8 of the
maximum charge pump flow per minute with a minimum fluid volume equal to 1/2 of the maximum
charge pump flow per minute. At the maximum return flow, this allows 30 seconds fluid dwell for
removing entrained air. This is adequate for a closed reservoir (no breather) in most applications. Position
the reservoir outlet (pump inlet) above the bottom of the reservoir to take advantage of gravity
separation and prevent large foreign particles from entering the charge inlet line. Use a 100 - 125 μm
screen over the outlet port. Position the reservoir inlet (fluid return) so that flow to the reservoir isdischarged below the normal fluid level, and directed into the interior of the reservoir for maximum dwelland efficient de-aeration. Use a baffle (or baffles) between the inlet and outlet ports to promote deaeration and reduce surging of the fluid.
System Parameters

Speed limits
Rated speed is the speed limit we recommend at full power condition and is the highest value at which
you can expect normal life. Maximum speed is the highest operating speed we permit. You cannot
operate above this speed without risk of immediate failure and loss of drive line power and hydrostatic
braking capacity (which may create a hazard). In mobile applications, you must apply this pump with aspeed speed below the stated maximum. Consult Pressure and Speed Limits, BC152886484313, when
determining speed limits for a particular application.
Inlet pressure
Control charge pump inlet conditions to achieve expected life and performance. Ensure a continuous
inlet pressure of not less than 0.8 bar absolute (not more than 6 in Hg vacuum). Normal pressures lessthan 0.7 bar absolute (greater than 9 in Hg vacuum) indicate inadequate inlet design or a restricted filter.
Pressures less than 0.7 bar absolute (greater than 9 in Hg vac) during cold start are possible, but should
improve quickly as the fluid warms. Never exceed the maximum inlet vacuum.
Theoretical output
The theoretical maximum flow at rated speed is a simple function of pump displacement and speed. Thisis a good gauge for sizing a companion motor. This does not take into account losses due to leakage orvariations in displacement.
Case pressure
Under normal operating conditions, the rated case pressure must not be exceeded. During cold startcase pressure must be kept below maximum intermittent case pressure. Size drain plumbing accordingly.

© Danfoss | May 2024

BC152886482857en-000306 | 11

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Operating Parameters
System pressure
System pressure is the differential pressure between high pressure system ports. It is the dominantoperating variable affecting hydraulic unit life. High system pressure, which results from high load,
reduces expected life. Hydraulic unit life depends on the speed and normal operating, or weighted
average, pressure that can only be determined from a duty cycle analysis.
Application pressure - is the high pressure relief or pressure limiter setting normally defined within theorder code of the pump. This is the applied system pressure at which the driveline generates the
maximum calculated pull or torque in the application. Maximum Working Pressure - is the highest
recommended Application pressure.
Maximum working pressure is not intended to be a continuous pressure. Propel systems with
Application pressures at, or below, this pressure should yield satisfactory unit life given propercomponent sizing.
Maximum pressure is the highest allowable Application pressure under any circumstance. Applicationpressures above Maximum Working Pressure will only be considered with duty cycle analysis and factory
approval.
Minimum pressure must be maintained under all operating conditions to avoid cavitation.

W Warning
All pressure limits are differential pressures referenced to low loop (charge) pressure. Subtract low looppressure from gauge readings to compute the differential.

Hydraulic Fluid Parameters
Hydraulic fluid
Ratings and data are based on operating with hydraulic fluids containing inhibitors to prevent oxidation,
rust, and foam. These fluids must possess good thermal and hydrolytic stability to prevent wear, erosion,and corrosion of the internal components.

C Caution
Never mix hydraulic fluids of different types.
Temperature and viscosity
Ensure the application satisfies temperature and viscosity requirements concurrently. The data shown in
the tables on Hydraulic Fluid Parameters on page 10, assume petroleum-based fluids.
High temperature limits apply at the hottest point in the transmission, which is normally the case drain.
Always run the pump at or below the continuous temperature. Never exceed maximum temperature.
Durability of transmission components is not affected by cold oil, but it may affect the ability of oil to flow
and transmit power. Keep temperatures 16 °C [30 °F] above the pour point of the hydraulic fluid. The
minimum temperature relates to physical properties of component materials.
For maximum unit efficiency and bearing life, keep fluid viscosity in the continuous viscosity range.
During brief occasions of maximum ambient temperature and severe duty cycle operation, minimum
viscosity may occur. The system should encounter maximum viscosity only at cold start.
Size heat exchangers to keep the fluid temperature and viscosity within these limits. Test the system toverify that these temperature limits are not exceeded.

12 | © Danfoss | May 2024

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Operating Parameters
Sizing Equations
Use these equations to help choose the right pump size and displacement for your application.

Based on SI units

Based on US units

Flow

=

Vg • n • η v
1000(l/min)=TorqueInput torque M =Vg • ′p
20 • π • η m(N•m)

Input torque M =

Power

•n•π
Input power P = M= 600 • η
30 000(kW)M•n•π
Input power P = 198= 1714 • η000

Q • ′pt

Vg • n • η v
231(US gal/min)Vg • ′p2 • π • ηm(lbf•in)Q • ′p(hp)
t

Variables
SI units [US units]© Danfoss | May 2024

Vg

= Displacement per revolution cm3/rev [in3/rev]PO= Outlet pressure bar [psi]Pi= Inlet pressure bar [psi]∆p= pO - pi (system pressure) bar [psi]n= Speed min-1 (rpm)ηv= Volumetric efficiency

ηm= Mechanical efficiency

ηt= Overall efficiency (ηv • ηm)

BC152886482857en-000306 | 13

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
System Design Parameters

Fluid and Filtration
To prevent premature wear, use only new clean fluid. Use a filter capable of controlling fluid cleanlinessto ISO 4406 Class 22/18/13 (SAE J1165).
Locate the filter on the inlet (suction filtration) or discharge (charge pressure filtration) side of the charge
pump: 4T axial piston pumps are available with provisions for either configuration.
The selection of a filter depends on a number of factors including the contaminant ingression rate, thegeneration of contaminants in the system, the required fluid cleanliness, and the desired maintenanceinterval. Use filters that meet the above requirements of efficiency and capacity.
Filter efficiency can be measured with a Beta ratio (βX). For simple suction-filtered closed circuit
transmissions and open circuit transmissions with return line filtration, a filter with a β-ratio within therange of β35-45 = 75 (β10 ≥ 2) or better has been found to be satisfactory. For some open circuit systems,
and closed circuits with cylinders being supplied from the same reservoir, a higher filter efficiency isrecommended. This also applies to systems with gears or clutches using a common reservoir. For thesesystems, a charge pressure or return filtration system with a filter β-ratio in the range of β15-20 = 75 (β10 ≥10) or better is typically required.
Because each system is unique, only a thorough testing and evaluation program can fully validate thefiltration system. Please see Design Guidelines for Hydraulic Fluid Cleanliness, BC152886482150, Technical
Information for more information.
Filtration Configuration
Locate the filter on the inlet (Suction filtration) or discharge (Charge pressure filtration) side of theexternal charge pump.
Suction filtration
Filter
To low pressur eside of loop andservo contro l

Reservoir

Chargepum pStrainer

Chargereliefvalve
To pump caseInternal

P400162

Charge pressure filtration, full flow
Filter
To low pressure
side of loop andservo control

Chargepump

Reservoir

Chargereliefvalve
To pump caseInternal

Strainer
P400163

14 | © Danfoss | May 2024

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
System Design Parameters
Mounting Flange Loads
Adding tandem mounted auxiliary pumps and/or subjecting pumps to high shock loads may result inexcessive loading of the mounting flange. Design pump applications to stay within the allowable shockload and continuous load moments.
Shock load moment MS is the result of an instantaneous jolt to the system. Rated (continuous) load
moments MR are generated by the typical vibratory movement of the application.
Estimated maximum and continuous acceleration factors for some typical applications are shown in thetable.
Applications which experience extreme resonant vibrations may require additional pump support.
Exceeding the allowable overhung values listed below will require additional pump support.
G-factors for sample applications
Application

Continuous (vibratory)
acceleration(GR)

Maximum (shock) acceleration(GS)

Skid steer loader

410Trencher (rubber tires)

3

8Asphalt paver

2

6Windrower

2

5

Turf care vehicle

1.5

4

Vibratory roller

610

Allowable overhung load moments
Rated load moment (MR)Shock load moment (MS)1441 N•m [12750 in•lbf]

3413 N•m [30200 in•lbf]

Estimating Overhung Load Moment
MR = GR (W1L1 + W2L2 + ... +WnLn)
MS = GS (W1L1 + W2L2 + ... +WnLn)
Where:© Danfoss | May 2024

MR

Rated load moment N•m [lbf•in]MS

Shock load moment N•m [lbf•in]GR

Rated (vibratory) acceleration (G-factors: unitless)GS

Maximum shock acceleration (G-factors: unitless)W

Weight of the pump N [lbf]L

Distance from mounting flange to the center of gravity mm [in]BC152886482857en-000306 | 15

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
System Design Parameters
Overhung load moments
Mounting flange

Pump 1
Center of gravity
Pump 2Center of gravity

L1
L2

P400164

Case Drain
The front and rear pumps are connected by cast passages in the housing. The charge relief valve
discharges oil into the front housing. In order to provide positive housing flow thru both pumps, use ofrear case drain is required. The front case drain should only be used if the pumps are used as a common
drain manifold for the vehicle whereas external drain flow is brought into the rear case port anddischarged out the front.
External Shaft Load and Bearing Life
Bearing life is a function of speed, pressure, and swashplate angle, plus any external loads. Other factorsthat affect life include fluid type, viscosity, and cleanliness.
In vehicle propulsion drives with no external loads—where the speed, pressure, and swashplate angle areoften changing—normal bearing B10 (90% survival) life exceeds the hydraulic unit life.
In non-propel drives, such as conveyors or fan drives, the operating speed and pressure may be nearly
constant leading to a distinctive duty cycle compared to that of a propulsion drive. In these types ofapplications, we recommend a bearing life review. 4T axial piston pumps use bearings that can accept
some incidental external radial and thrust loads. However, any amount of external load reduces the
expected bearing life.
The allowable radial shaft loads are a function of the load position, orientation, and operating pressuresof the hydraulic unit. In applications where you cannot avoid external shaft loads, minimize the impact onbearing life by orienting the load to the 0° or 180° position.
The maximum allowable radial load is calculated as: Re = Me / L
Where:

16 | © Danfoss | May 2024

L

Distance from mounting flange to point of load

Me

Maximum external moment

Re

Maximum radial side load

Tout

Thrust load

FB

Load to cylinder block kit

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
System Design Parameters
Allowable shaft loads
Displacement (cm3)

41

51

Me
N•m [in•lbf]

111
[982]

90
[800]

TOUT
N [lbf]

1110
[250]

1110
[250]

Avoid thrust loads in Tin direction.
If continuously applied external radial loads are 25% of the maximum allowable or more, or thrust loads
are known to occur, contact your Danfoss representative for an evaluation of unit bearing life.
Use clamp-type couplings where radial shaft side loads are present.
External shaft load orientation
FB

0 Re

L

Re
Tout

90 Re

270 ReTin

180 ReP400165

Use the table and drawing to determine maximum allowable radial loads (Re), based on the maximum
external moment (Me) and the distance (L) from the mounting flange to the load.
Hydraulic Unit Life
Hydraulic unit life is the life expectancy of the hydraulic components. Hydraulic unit life is a function of
speed and system pressure. However, system pressure is the dominant operating variable. High pressure,which results from high load, reduces expected life.
Design the hydraulic system to a projected machine duty cycle. Know the expected percentages of time
at various loads and speeds. Ask your Danfoss representative to calculate an appropriate pressure based
your hydraulic system design. If duty cycle data is not available, input power and pump displacement areused to calculate system pressure.
All pressure limits are differential pressures (referenced to charge pressure) and assume normal chargepressure.
4T axial piston pumps will meet satisfactory life expectancy if applied within the parameters specified inthis bulletin. For more detailed information on hydraulic unit life see BC152886484313, Pressure andSpeed Limits.

© Danfoss | May 2024

BC152886482857en-000306 | 17

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
System Design Parameters
Efficiency Graphs
The following performance map provides typical volumetric and overall efficiencies for 4T axial piston
pumps. These efficiencies apply for all 4T axial piston pumps at maximum displacement.
Pump performance as a function of operating speed at maximum displacement*
100

Efficiency — %- 170 bar [2500 psi]
Volumetric Efficiency

95

90

85

80

e
Ov

0

ric Efficiency - 345 bar [5000 psi]umet
Vol Overall Efficie
nc y - 1
7 0 b ar
[2500
psi]
345
y
c
b
ar
n
[5000 psi]
cie
i
f
f
E
rall

25
50
75
Speed, % of Rated Speed

100
P100401E

The following performance map provides typical pump overall efficiencies at various operating
parameters. These efficiencies also apply for all 4T axial piston pumps at maximum displacement.
Pump performance at select operating parameters at maximum displacement*

System Pressure

psi
5000
4000

bar
350
300
250

3000
2000

200
150

%
88

100
1000
0

87%

85%

80%

50
0

0

25
50
75
Speed, % of Rated Speed

100

P100402E* Assumes viscosity in the continuous range

18 | © Danfoss | May 2024

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options

Charge Pump
An external charge pump is required on all 4T axial piston pumps units applied in closed circuit
installations to make up for internal leakage, to maintain positive pressure in the main circuit, and to
replace any leakage losses from external valving or auxiliary systems.
The total charge flow requirement is the sum of the charge flow requirement of each of the components
in the system. When initially sizing and selecting hydrostatic units for an applications, it is frequently notpossible to have all of the information necessary to accurately evaluate all aspects of charge pump size
selection. The following procedure will assist the designer in arriving at an initial charge pump selection
for a typical application.
In most 4T axial piston pump applications a general guideline is that the charge pump displacement(CPG) should be equal to or greater than 10% of the total displacement (TD) of all axial piston units in thesystem. This rule assumes that all units are of high speed, axial piston or bent axis design.
Particular application conditions may require a more detailed review of charge pump sizing. System
features and conditions that may invalidate the 10% of displacement rule include (but are not limited to):•Operation at low input speeds (below 1500 rpm)•

Shock loadings•

Excessively long system lines•

Auxiliary flow requirements•

Use of low speed, high torque motors

If a charge pump of sufficient displacement to meet the 10% of displacement rule is not available or if anyof the above conditions exist which could invalidate the 10% rule, contact your Danfoss representative.
A charge pump sizing worksheet can be found in BC157786484430, Selection of Driveline Components.
Charge Pump Sizing Example:
A system consists of 4T 41cc Pump driving two Series 40 -M35 Fixed Motors:
TD = 41 + 41 + 35 +35= 152 cm3••

CPD = 10 % x TD = 15.2 cm3This requires a charge pump displacement of 15.2 cm3 .
Charge Relief ValveThe charge relief valve maintains charge pressure at a designated level. 4T axial piston pumps come withdirect-acting poppet style charge relief valves. The valve setting is set at the factory. The setting is screw
adjustable.
The charge pressure settings are nominal values and are based on the charge flow across the charge
relief valve with a fluid viscosity of 28 mm2/s (cSt) [130 SUS] and a pump input speed of 1800 min-1(rpm).
Actual charge pressure differs slightly from the nominal setting when different input speeds are used.
The charge setting is a differential pressure (referenced to case pressure) and measured with the piston
pump at zero swashplate angle (neutral). Charge pressure drops slightly when the pump is in stroke due
to flow demands.
The charge pressure setting for pumps without an internal charge pump is set with an assumed charge
flow of 38 l/min (10 US gal/min). These units must have adequate charge flow supplied to the charge
inlet in order to maintain charge pressure at all times.

© Danfoss | May 2024

BC152886482857en-000306 | 19

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options
Charge Relief ValveTo CaseTo Low Sideof Working
Loop & Servo
Control

From Charge
Pump
P100392E

C Caution
Incorrect charge pressure settings may result in the inability to build required system pressure, inability
to control pump, and/or inadequate loop flushing flows. Maintain correct charge pressure under all
operating conditions.

Overpressure Protection
4T axial piston pumps are available with a combination charge check and high pressure relief valve
assembly. High pressure relief valves come in a range of settings as shown in the model code. You may
specify individual port pressure settings. The high pressure relief valve settings are a differential pressure(referenced to charge pressure) and are set at 3.8 l/min (1 US gal/min) of flow.
We can equip pumps with charge check valves only, if high pressure relief valve protection is notnecessary.
Charge Check and High Pressure Relief Valve
Charge pressure
High pressure
side of working loop

Charge check andhigh pressure
relief valve

P100393E

C Caution
High pressure relief valves are for transient overpressure protection, not for continuous pressure control.
Operation over relief valves for extended periods of time results in severe heat build up. High flows overrelief valves may result in pressure levels exceeding the nominal valve setting and potential damage tosystem components.

20 | © Danfoss | May 2024

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options
Bypass Valve
4T axial piston pumps are available with an optional bypass function for use when pump shaft rotation is
not possible. Use the bypass function to bypass fluid around the variable displacement pump. For
example: you may move a disabled vehicle to a service location or winch it onto a trailer without
operating the prime mover.
The bypass valve is integral to the charge check/high pressure relief valve assembly. Depress theplungers located in the plugs of the valve assemblies to operate the bypass function. The valves remain
open until the prime mover is started. Charge pressure automatically closes them.
Charge Check and High Pressure Relief Valve with Bypass
Charge pressure
FLOW

BypassplungerHigh pressure
side of working
loop

Charge check andhigh pressure
relief valve
P100394E

C Caution
Damage to the hydraulic system may result from operating without charge flow. Bypass valves are formoving a machine or vehicle for very short distances at very slow speeds. They are NOT tow valves.

Displacement Limiters
4T axial piston pumps are available with adjustable mechanical displacement (stroke) limiters located in
the servo covers. The maximum displacement of the pump can be limited to any value from its maximum
displacement to zero in either direction. The limiters are factory set slightly beyond the maximum
displacement of the pump. Displacement limiters may not be suited to all applications.
Series 42 pump displacement limiters

Shaft Options
4T axial piston pumps are available with a variety of splined and tapered shaft ends. The accompanying
table shows available shaft sizes and torque ratings. Maximum torque ratings are based on shaft torsional
strength and assume a maximum of 200 000 load reversals.

© Danfoss | May 2024

BC152886482857en-000306 | 21

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options
Use ANSI B92.1 Class 5 mating splines for splined output shafts. Danfoss external splines are modified
Class 5 fillet root side fit. The external spline major diameter and circular tooth thickness dimensions are
reduced in order to insure a clearance fit with the mating spline.
Shaft Availability and Torque Rating*
Shaft

Max. torque

15 tooth spline, 16/32 pitch

362 N•m [3200 in•lbf ]19 tooth spline, 16/32 pitch

734 N•m [6500 in•lbf ]* The limitations of these input shafts constrain the allowable auxiliary coupling torque.

Auxiliary Mounting Pads
Auxiliary mounting pads are available on all 4T axial piston pumps to mount auxiliary hydraulic pumps.
We include a sealed (oil tight) shipping cover as standard equipment. The shipping cover seals casepressure and you can use it as a running cover if desired.
Since the auxiliary mounting pad operates under case pressure, you must use an O-ring to seal theauxiliary pump to the pad. The drive coupling is lubricated with oil from the main pump case.
Spline specifications and torque ratings are shown in the accompanying table.
All mounting pads meet SAE J744 specifications.

•
•
•

•

The sum of main and auxiliary pump torque must not exceed stated maximum.
All torque values assume a 58 RC shaft spline hardness on mating pump shaft. Maximum torque isbased on maximum torsional strength and 200 000 load reversals.
Applications with severe vibratory or high G-force (shock) loading may require additional structural
support to prevent leaks or mounting flange damage. Refer to Mounting flange loads for additional
information.

Auxiliary Pad*
Pad size

SplineMinimum spline length(mm [in])Maximum torque (N•m[lbf•in])

SAE A

9 tooth 16/32 pitch

13.5 [0.53]

107 [950]

SAE A special

11 tooth 16/32 pitch

13.5 [0.53]

147 [1300]

SAE A special

13 tooth 16/32 pitch

14.2 [0.56]

248 [2200]

SAE B

13 tooth 16/32 pitch

14.2 [0.56]

248 [2200]* Allowable Auxiliary coupling torque is subject to limitations of the input shaft.
This drawing provides the dimensions for the auxiliary pump mounting flange and shaft. Auxiliary pump
mounting flanges and shafts with these dimensions are compatible with the auxiliary mounting pads on
4T axial piston pumps. For auxiliary pad dimensions, see Auxiliary Mounting Pads on page 47.
C
max.

B
max.

Without
UndercutWith
Undercut

Mounting
FlangeEm ax.
Dm ax.

R 0.8 (.03)
max.
Coupling

22 | © Danfoss | May 2024

F min.
2.3 (.09)
Cutter clearance0¯ P -0.05(+.000)(-.002)

Spline Engagement
for TorqueP001614E

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options
Auxiliary pump mating dimensions
Pad Size

P

B

C

D

E

F

SAE A mm [in]82.55 [3.250]

8.1 [0.32]

12.7 [0.500]

44 [1.73]

15 [0.59]

13.5 [0.53]

SAE B mm [in]101.6 [4.000]

11.4 [0.45]

15.2 [0.60]

46 [1.81]

17.5 [0.69]

14.2 [0.56]

Center Coupling
The two pump shafts are connected with a center-section coupling that is a 22 tooth spline with a 24/48
pitch. The torque transmitted through the center coupling is the sum of the rear kit torque and theauxiliary pump torque. The maximum torque rating of the auxiliary pad may be reduced from the values
in the above table due to center coupling limitations.
22 tooth Center-Section Coupling Torque Rating
RatingTorque in N•m [lbf•in] 22T

Maximum

347 [3071]

Continuous

243 [2151]

Control Selection
4T axial piston pumps use a servo control system with two types of control options. Manual Displacement
Controls (MDC) are feedback controls that provide and maintain a set displacement for a given input. The
MDC includes options for a Neutral Start Switch (NSS), backup alarm , and a solenoid override to neutral.
Non-Feedback Proportional Hydraulic controls (NFPH) is available to control the pump without
mechanical feedback.
All controls provide smooth, stepless positive control of the transmission in either direction. Optional
servo supply and drain orifices are available for special response needs.
Typical Control Applications
MachineRoller/compactor

Skid steer loader

PropelArticulated loader

PropelUtility tractor

PropelWindrower

PropelPropelChain drive

Ag sprayer

PropelSpecialized harvesters(sod, fruit, nut, etc.)

PropelAuxiliary drive

Commercial mower

PropelRock drill

PropelSweeper

NFPH

Vibratory drive
PropelDrill rig

MDC

PropelAsphalt paver

Trencher© Danfoss | May 2024

Function

Drill drive
Pull downe
PropelFan

BC152886482857en-000306 | 23

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options
Typical Control Applications (continued)
MachineFunction

Aerial lift

PropelFork lift

PropelBrush / stump cutter

24 | © Danfoss | May 2024

MDC

NFPH

PropelCutter drive

Airport vehicle

PropelDumper

PropelBC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options
Manual Displacement Control (MDC)
The Manual Displacement Control (MDC) converts a mechanical input signal to a hydraulic signal. The
hydraulic signal positions the servo piston, tilting the swashplate to vary the pump’s displacement andflow direction.
The position of the swashplate is proportional to the mechanical input signal. The control has mechanicalfeedback that regulates the servo valve in relation to swashplate position to maintain displacement at
the commanded level regardless of changes in system pressure.
The full featured 4T axial piston pumps manual control consists of two manual displacement controls
with backup alarm swiches. One of the controls incorporate a neutral override (NOR) solenoid and brakerelease port. The other control housing drains through the first control housing to provide neutral
override function.
Manual controls for use on one pump are also available and can be used in combination with anothertype of control on the other pump. The servo control valve has variable geometry porting to regulate
swashplate response relative to input command. The control performs small displacement changecommands with maximum controllability throughout the entire stroking range of the pump. It completes
large displacement change commands with rapid swashplate response. Optional servo supply and drain
orifices are available for special response needs.
The control also has a full over-travel spool that allows input at a faster rate than swashplate movement
without damage to the control. Any swashplate position error is feed back to the servo valve for instantcorrection.
Features and Benefit of MDC

•
•
•
•
•
•
•

The MDC is a high gain control: Small movements of the control handle move the servo valve to fullopen position porting maximum flow to the servo cylinder.
The full over-travel spool design allows rapid changes in input signal without damaging the control
mechanism.
The MDC provides a fast response with low input force.
Precision parts provide repeatable and accurate displacement settings.
Mechanical feedback maintains pump displacement regardless of changes in system pressure.
The operator is isolated from swashplate vibration.
The swashplate and servo cylinder, as well as the control valve, are spring centered so the pump
returns quickly to neutral in the absence of control input.

The pump returns to neutral:• if the prime mover is shut down;••© Danfoss | May 2024

if the external control linkage fails at the control handle;
if there is a loss of charge pressure.

BC152886482857en-000306 | 25

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options
Control Input Signal
The figure and table below relate the input electrical signal to pump displacement, (swashplate position),for each coil configuration.
Pump displacement versus Electrical signal

100%

-a
Displacement

-b

a

b

100%
P001015E

Response TimeYou can tailor the time to change from zero to maximum displacement using orifices incorporated in thegasket between the control and pump housing. Using orifices you can match swashplate response to theacceleration and deceleration requirements of your application. Verify proper orifice selection by testing.
MDC Response Time (Maximum to Maximum)
Frame size (cm3)

Fast (no orifice)MediumSlow (standard)

41/51

0.6 sec

1.6 sec

2.5 sec

Neutral to maximum swashplate response is approximately 60% of the time for maximum to maximum
sawashplate travel. For other response times please contact your Danfoss representative.
MDC Schematic

M4
M5

P100404E

26 | © Danfoss | May 2024

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options
Cross-section of MDC
Servo Piston

Feedback
Linkage

Servo Control
Valve MDC Handle
Charge Pressure

P100403E

Control Handles
Either straight or clevis (offset) style control handles are available for the MDC. The straight style handle
minimizes the overall height of the pump and control. The clevis style handle provides additional
clearance between the handle and control housing and works well for clevis style linkage installations.
Maximum allowable input torque at the control handle is 17 N•m (150 lbf•in). The maximum allowablebending moment is 4 N•m (35 in•lbf ).
Pump Flow Direction with MDC
Input Shaft Rotation

CW

CCW

Handle of rotation

CW

CCW

CW

CCW

Port A flow

Out

In

In

Out

Port B flow

In

Out

Out

In

High pressure servo guage port

M4

M5

M4

M5

MDC Handle Options

P100407E

Electric Solenoid Override to Neutral
This normally open solenoid valve (C) shunts both ends of the servo piston. This prevents the pump fromstroking. When energized, the valve closes, allowing the pump to operate normally. This option is ideallysuited for operator presence or auto-resume functions without prime mover shut down. This solenoid isavailable in 12 or 24 Vdc with 2 Amp. maximum current draw. It is available with DEUTSCH 2-way or witha Packard Weather-Pack 2-way shroud connector.

© Danfoss | May 2024

BC152886482857en-000306 | 27

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options
Emergency Override to Neutral with Port for Brake Pressure Release
This solenoid valve (C) operates as the override to neutral above, and drains a spring-applied,hydraulically-released brake (port X7). Energizing the valve allows the pump to operate as normal, while
also charging port X7 to release the brake. This option is ideally suited for emergency stop functions
without prime mover shut down. The solenoid is available in 12 or 24 Vdc with 2 Amp. maximum current
draw. It is available with DEUTSCH 2-way or with a Packard Weather-Pack 2-way shroud connector.
Electric Override to Neutral Specifications
Solenoid State at Override Activation

De-energized

Voltage12 or 24 Vdc

Maximum Current

2A

Hydraulic Schematic for MDC with Override Options

X7
C

L2
(from
charge pump)

M5

M4
P400167

28 | © Danfoss | May 2024

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options
Neutral Start Switch (NSS)This option provides an electrical switch contact that is closed when the control handle is in its neutral(0°) position. The switch contact opens when the control handle rotates approximately 1.5° to 2°
clockwise (CW) or counterclockwise (CCW) from neutral.
The switch is rated for 5 Amp. inductive load at 12 or 24 Vdc. It is available with screw terminals (noconnector) or with a Packard Weather-Pack 2-way tower connector or DEUTSCH 2-way connector..
Wire the NSS in series with the engine starting circuit to ensure the pump is in neutral position before
allowing the engine to start.
Neutral Start Switch Specifications
Switch Neutral Position

ClosedVoltage12 or 24 Vdc

Current Rating

5A

Neutral Play± 2°

NSS with Back-up Alarm (BUA) Switch
The BUA switch contact is open until the control handle rotates 2.6° to 3.75° from neutral. The BUA switch
closes when the control handle rotates either clockwise (CW) or counterclockwise (CCW) from neutral(choose one direction only). The NSS function operates as described above.
The BUA contacts are rated for 2.5 Amp. resistive load at 12 or 24 Vdc. The NSS contacts are rated for 5
Amp. inductive load at 12 or 24 Vdc. This switch is available with screw terminals (no connector) or with a
Packard Weather-Pack 4-way tower connectoror Deutsch 2-way, 4-way connector..
Wire the NSS as described above. Wire the BUA switch in series with a back-up alarm to have the alarmsound when the operator moves the pump control handle into reverse.
Backup alarm switch option
Switch Neutral Position

Open

Voltage12 or 24 Vdc

Current Rating

2.5 A

Alarm Direction

CW or CCW

Neutral Play± 2.6° to 3.75°

Connectors
For available connectors and dimensions, see outline drawings: Manual Displacement Control Options.

© Danfoss | May 2024

BC152886482857en-000306 | 29

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options
Hydraulic schematic for MDC with override options
and NSS(A) = Backup alarm switch contacts (green wire)(closed in reverse)(B) = Neutral start switch w/ backup alarm(C) = Electric solenoid override to neutral w/
brake release

M4(D) = Neutral start switch contacts (black wire)(closed in neutral)

M5

B
D
A

X7

C

P100408E

30 | © Danfoss | May 2024

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options
Non-feedback, proportional hydraulic control (NFPH)
The non-feedback proportional hydraulic (NFPH) control is a hydraulic proportional control in which an
input pressure signal directly controls the pump servo piston to achieve pump displacement.
4T pumps with NFPH control have a special servo cylinder capable of providing proportional control witha hydraulic input.
Swashplate position is proportional to the differential signal pressure at ports X1 and X2, butdisplacement is also dependent on pump speed and system pressure. This characteristic of non-feedback
controls provides a natural power limiting function by reducing the pump swashplate angle as systempressure increases. The accompanying graph shows typical operating characteristics.
The system may require tuning through the pump orifice combinations, control pressure supply line
sizing, actuation device output pressure and flow adjustments to achieve proper vehicle performance
characteristics
Non-feedback proportional hydraulic control
schematic

Pump displacement versus signal pressure
Servo piston

X2 X1

L2

M5

Piston centering spring
P100412E

M4

P400169

Pump flow direction with NFPH control© Danfoss | May 2024

Input Shaft Rotation

CW

CCW

High pressure at port:

X1

X2

X1

X2

Port A flow

Out

In

In

Out

Port B flow

In

Out

Out

In

High servo gauge port

M4

M5

M4

M5

BC152886482857en-000306 | 31

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Features and Options
NFPH pump displacement to Input signal

6

ar
5b
tem
=3
4

sys
Dp

Dp

Displacement

ba
r

5b
sys

tem
=3
5

tem
=3
4
Dp

sys
Dp

sys

Signal Dp (bar)
15
6
ar

18

tem
=3
5

ba
r

100%

15

18

100%
P001628E

The Input Signal (Δp) values in the graph above are approximations at 1800 RPM and system delta
pressures as indicated in the graph above. The values are dependent on input speed and delta pressure
operating conditions.
Features and Benefits of the NFPH control

•
•
•
•

Eliminates mechanical linkage for flexibility of control design
Power limiting characteristic reduces machine power requirements
Compatible with dual axis joysticks for dual path applications
Smooth operation

Connectors and Port locations
Refer to outline drawings.

32 | © Danfoss | May 2024

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings
Manual Displacement Control (MDC)
Port Description
Charge Inlet Port “M6”Port ISO 11926-1 – 7/8 -14

Servo Pressure Gauge Port “M4”Port ISO 11926-1 – 9/16 -18

Servo Pressure Gauge Port “M5”Port ISO 11926-1 – 9/16 -18

System Port “B”
Port ISO 11926-1 – 1 5/16 -12

Z

System B Pressure Gauge Port “M2”Port ISO 11926-1 – 9/16 -18
Case Drain Port “L1”
Port ISO 11926-1 – 1 5/16 -12
System A Pressure Gauge Port “M1”

System Port “A”

Port ISO 11926-1 – 9/16 -18

Port ISO 11926-1 – 1 5/16 -12P400170

Z

CCW

CW

P400171© Danfoss | May 2024

Port

Description

Sizes

Port

Description

Sizes

A

System port "A"

1 5/16 - 12

M2

System "A" pressure gauge port "M1"

9/

B

System Port "B"

1 /16 - 12

M1

System "C" pressure gauge port "M1"

9/ - 18
16

C

System Port "C"

1 5/16 - 12

M2

System "D" pressure gauge port "M2"

9/

D

System Port "D"

1 5/16 - 12

M4 x2 Servo pressure gauge port "M4"

9/

L1

Case Drain Port "L1"

1 /16 - 12

M5 x2 Servo pressure gauge port "M5"

9/

5

5

16 - 18

16 - 18
16 - 18

16 - 18

BC152886482857en-000306 | 33

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings
Port

Description

Sizes

Port

L2

Case Drain Port "L2"

1 5/16 - 12

M6 x2 Charge inlet port "M6"

System "A" pressure gauge port "M1"

9/

M1

Description

Sizes
7/

8 - 1416 - 18

Charge Inlet Port “M6”Port ISO 11926-1 – 7/8 -14
Servo Pressure Gauge Port “ M4”Port ISO 11926-1 – 9/16 -18
Servo Pressure Gauge Port “ M5”Port ISO 11926-1 – 9/16 -18
System Port “D”
Port ISO 11926-1 – 1 5/16 -12

System D Pressure Gauge Port “M2”Port ISO 11926-1 – 9/16 -18
Case Drain Port “L2”
System C Pressure Gauge Port “M1”Port ISO 11926-1 – 1 5/16 -12Port ISO 11926-1 – 9/16 -18

System Port “C”
Port ISO 11926-1 – 1 5/16 -12

34 | © Danfoss | May 2024

P400172

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings
Dimensions
433.4 [17.06]
421.3 [16.59]
335.4 [13.20]
277 [10.91]
192 [7.56]

Charge Inlet Port “M6”180.34 [7.10]
Ø10.8±0.5
Thru

Port ISO 11926-1 – 7/8 -14

171.7 [6.76]

Servo Pressure Gauge Port “M4”Neutral Adjust

131.7 [5.19]
41.6 [1.64]

17 mm HEXPort ISO 11926-1 – 9/16 -18

Servo Pressure Gauge Port “M5”Port ISO 11926-1 – 9/16 -18

System B Pressure Gauge Port “M2”DISPLACEMENT LIMITEROPTION 0, N

Port ISO 11926-1 – 9/16 -18
G

Z

120
[4.72]

F

103[4.06]

G77[3.03]

38.5[1.52]

30[1.18]

F

83.2[3.28]

38.5[1.52]AUXILIARY MOUNTING PADOPTION J, K, S
System A Pressure Gauge Port “M1”

System Port “A”

Port ISO 11926-1 – 9/16 -18

Port ISO 11926-1 – 1 5/16 -12

APPROXIMATE CENTEROF GRAVITY

Case Drain Port “L1”
Port ISO 11926-1 – 1 5/16 -12

System Port “B”
Port ISO 11926-1 – 1 5/16 -12© Danfoss | May 2024

P400173

BC152886482857en-000306 | 35

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation DrawingsZ
126.5[4.98]

126.5[4.98]
82.3[3.24]

BOTH SIDESSPOT FACE(M5)

89[3.50]

109.5[4.31]
BOTH SIDESSPOT FACE(M4)

88[3.46]
CL

Shaft
Center Line CL

Section G-G

Section F-F

APPROXIMATECENTEROF GRAVITY

276.06[10.87]39[1.54]

32[1.26]

50[1.97]

Ø17.57 ±0.30[0.69 ±0.01]
THRU
6X
+0
Ø127 -0.05+0[5 -0.002 ]
90.5[3.56]
2X

81[3.19]
2X

P400174

Adjustable displacement limiters
Shaft rotation

CW

CCW

Displacement limiter side

1

2

1

2

Limited flow through port

B, C

A, D

A, D

B, C

Determine rotation by viewing pump from the input shaft end. Contact your Danfoss representative for
specific installation drawings.

36 | © Danfoss | May 2024

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings
274.55[10.81]0
12.7 - 0.5[0.5 0 ]- 0.02LIFTING BRACKETLIFTING BRACKET

29.23[1.15]
BOTH HANDS

22[0.87]
2X
90°±8°BOTH
HANDLES2XM 10X1.5-6H Thd
16 MIN Full Thd Depth

114[4.49]

14[0.55]
109.45[4.31]

361.4[14.23]342.4[13.48]192[7.56]

Charge Inlet Port “M6”178
[7.01]

Port ISO 11926-1 – 7/8 -14

48.6[1.91]

Servo Pressure Gauge Port “M4”Charge Relief Valve12.5 mm External Hex
Neutral Adjust

Port ISO 11926-1 – / -18
9 16

17 mm HEX
Servo Pressure Gauge Port “M5”

System Port “D”

Port ISO 11926-1 – 9/16 -18

Port ISO 11926-1 – 1 5/16 -1288[3.46]

120[4.72]

103[4.06]

CL

113.3[4.46]

77[3.03]
38.5[1.52]
E

19.2 [0.76]

38.5[1.52]

Section E-E

E

Case Drain Port “L2”Port ISO 11926-1 – 1 5/16 -12
System D Pressure Gauge Port “M2”111
[4.37]

Port ISO 11926-1 – 9/16 -18
System C Pressure Gauge Port “M1”Port ISO 11926-1 – 9/16 -18
System Port “C”
Port ISO 11926-1 – 1 5/16 -12© Danfoss | May 2024

252.3
[9.93]

212.3[8.36]

P400175

BC152886482857en-000306 | 37

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings
Non-Feedback, Proportional Hydraulic (NFPH)
Port Description
Charge Inlet Port “M6”Port ISO 11926-1 – 7/8 -14
Servo Pressure Gauge Port “M4”Servo Pressure Gauge Port “M5”Port ISO 11926-1 – 9/16 -18

Port ISO 11926-1 – 9/16-18

System Port “B”
Port ISO 11926-1 – 1 5/16 -12

Z

System B Pressure Gauge Port “M2”Port ISO 11926-1 – 9/16 -18

Case Drain Port “L1”
Port ISO 11926-1 – 1 5/16 -12

System Port “A”

System A Pressure Gauge Port “M1”Port ISO 11926-1 – 1 5/16 -12Port ISO 11926-1 – 9/16 -18

P400176

Z

CCW

CW

P400177

38 | © Danfoss | May 2024

Port

Description

Sizes

Port

Description

Sizes

A

System port "A"

1 5/16 - 12

M1

System “C” pressure gauge port “M1”9/

System “D” pressure gauge port “M2”

9/ - 1816

16 - 18

B

System Port "B"

1 /16 - 12

M2

C

System Port "C"

1 5/16 - 12

M4 x2 Servo pressure gauge port “M4”

9/ - 18
16

D

System Port "D"

1 5/16 - 12

M5 x2 Servo pressure gauge port “M5”9/

L1

Case Drain Port "L1"

1 /16 - 12

M6 x2 Charge Inlet port “M6”

7/ - 14
8

L2

Case Drain Port "L2"

1 5/16 - 12

X1

5

5

Control Port “X1”

16 - 18

9/

16

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings
Port

Description

Sizes

Port

Description

Sizes

M1

System "A" pressure gauge port "M1"

9/ - 18
16

X2

Control Port “X2”9/

M2

System "B" pressure gauge port "M2"

9/ - 18
16

16

Control Port “X2”Port ISO 11926-1 – 9/16 -18
Control Port “X1”Port ISO 11926-1 – 9/16 -18

Control Port “X1”Control Port “X2”Port ISO 11926-1 – 9/16 -18

Port ISO 11926-1 – 9/16 -18

Charge Pressure Inlet Port “M6”Port ISO 11926-1 – 7/8 -14
Servo Pressure Gauge Port “M4”Port ISO 11926-1 – 9/16 -18
Servo Pressure Gauge Port “M5”Port ISO 11926-1 – 9/16 -18
System Port “D”
Port ISO 11926-1 – 1 5/16 -12

System D Pressure Gauge Port “M2”Port ISO 11926-1 – 9/16 -18
Case Drain Port “L2”
System C Pressure Gauge Port “M1”Port ISO 11926-1 – 1 5/16 -12Port ISO 11926-1 – 9/16 -18
System Port “C”
Port ISO 11926-1 – 1 5/16 -12© Danfoss | May 2024

P400178

BC152886482857en-000306 | 39

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings
Dimensions
433.4 [17.06]
421.3 [16.59]
335.4 [13.20]
277 [10.91]
195.9 [7.71]

Charge Inlet Port “M6”

192 [7.56]
Ø10.8±0.5
Thru

Port ISO 11926-1 – 7/8 -14

171.7 [6.76]

Servo Pressure Gauge Port “M4”131.7 [5.19]
41.6 [1.64]

Servo Pressure Gauge Port “M5”Port ISO 11926-1 – 9/16 -18

Port ISO 11926-1 – 9/16 -18
System B Pressure Gauge Port “M2”DISPLACEMENT LIMITEROPTION 0, N

Port ISO 11926-1 – 9/16 -18
G

Z

120
[4.72]

F

103[4.06]

G77[3.03]

38.5[1.52]

30[1.18]

F

83.2[3.28]

38.5[1.52]AUXILIARY MOUNTING PADOPTION J, K, S
System A Pressure Gauge Port “M1”

System Port “A”

Port ISO 11926-1 – 9/16 -18

Port ISO 11926-1 – 1 5/16 -12

APPROXIMATE CENTEROF GRAVITY
System Port “B”
Port ISO 11926-1 – 1 5/16 -12

40 | © Danfoss | May 2024

Case Drain Port “L1”
Port ISO 11926-1 – 1 5/16 -12P400179

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation DrawingsZ
157.3[6.19]

157.3[6.19]
82.3[3.24]
BOTH SIDESSPOT FACE(M5)

89[3.50]

141.3[5.56]
BOTH SIDESSPOT FACE(M4)

CL

Section F-F

APPROXIMATECENTER OFGRAVITY88[3.46]
Shaft
Center Line CL

Section G-G

239.3[9.42]

38.7[1.52]

32[1.26]

50[1.97]

Ø17.57 ±0.30[0.69 ±0.01]
THRU
6X
+0
Ø127 -0.05+0[5 -0.002 ]
90.5[3.56]
2X© Danfoss | May 2024

81
[3.19]
2X

P400180

BC152886482857en-000306 | 41

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings
Control Port “X1”Control Port “X2”Port ISO 11926-1 – 9/16 -18

Port ISO 11926-1 – 9/16 -18

012.7 - 0.5

CL[0.5 0 ]- 0.02

Lifting Bracket

4X 127.8 [5.03]

A

A

55
[2.17]

58.5[2.30]

Section A-A
55[2.17]

58.5[2.30]

114[4.49]
2XM 10X1.5-6H Thd
16 MIN Full Thd Depth

Control Port “X1”Control Port “X2”Port ISO 11926-1 – 9/16 -18

Port ISO 11926-1 – 9/16 -18

90.8[3.57]

14[0.55]

Lifting Bracket

293.2[11.54]361.4[14.22]342.4[13.48]252.3[9.93]

88[3.46]
212.3[8.36] 192[7.56]

Charge Inlet Port “M6”CL

178
[7.01]
111[4.37]

Port ISO 11926-1 – / -14
7 8

Servo Pressure Gauge Port “M4”

48.6
[1.91]

Port ISO 11926-1 – 9/16 -18

Charge Relief Valve12.5 mm External Hex

Section E-E

System D Pressure
Gauge Port “M2”Servo Pressure Gauge Port “M5”Port ISO 11926-1 – 9/16 -18

Port ISO 11926-1 – 9/16 -18
120[4.72]

103[4.06]
113.3[4.46]

77[3.03]
38.5[1.52]
E

19.2 [0.76]

38.5[1.52]

E

Case Drain Port “L2”Port ISO 11926-1 – 1 5/16 -12

System C Pressure Gauge Port “M1”Port ISO 11926-1 – 9/16 -18

42 | © Danfoss | May 2024

System Port “C”

System Port “D”

Port ISO 11926-1 – 1 5/16 -12Port ISO 11926-1 – 1 5/16 -12P400181

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings
Shaft Options
57[2.243]55[2.165]33.8±0.5[1.331±.02]
FULL SPLINECOUPLING MUST NOT PROTRUDE
BEYOND THIS POINT

Ø27.8 MAX
[1.1]

19 TEETH 16/32 PITCH
30° PRESSURE ANGLE
30.163 PITCH DIAFILLET ROOT SIDE FITANSI B92.1-1970 CLASS 5
ALSO MATES WITH
FLAT ROOT SIDE FIT

R2.7±0.4[.11±.02]

Ø31.24 ±0.09[1.23±.004]

40[1.576]38.6 ±0.5[1.518 ±.02]

OPTION E
19 TOOTH SPLINE SHAFT

COUPLING MUST NOT PROTRUDE
BEYOND THIS POINT

23.4±0.5[.92±.02]
FULL SPLINE

15 TEETH 16/32 PITCH
30° PRESSURE ANGLE
23.813 PITCH DIAFILLET ROOT SIDE FITANSI B92.1-1970 CLASS 5
ALSO MATES WITH
FLAT ROOT SIDE FIT

Ø22.13 MAX[.871]

Ø25.3 ±0.09[.998±.004]

OPTION D
15 TOOTH SPLINE SHAFT
P400182© Danfoss | May 2024

BC152886482857en-000306 | 43

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings
Displacement LimiterCL72[2.835]

39.6[1.559]344.4[13.559]105.8[4.165]OPTION A-F
DISPLACEMENT LIMITER
SIDE 1 FRONTOPTION 1-6 & A-F
DISPLACEMENT LIMITER
SIDE 2 REAR

160.8
[6.33]OPTION 1-6
DISPLACEMENT LIMITERNFP SIDE 1 FRONT
160.8[6.33]

129[5.078]OPTION 1-6 & A-F
DISPLACEMENT LIMITER
SIDE 2 FRONTOPTION A-F
DISPLACEMENT LIMITER
SIDE 1 REAROPTION 1-6
DISPLACEMENT LIMITERNFP SIDE 1 REAR

129
[5.078]344.4[13.559]105.8[4.165]

39.6[1.559]72[2.835]
CL

P400183

44 | © Danfoss | May 2024

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings
By-pass Valve

214.7[8.453]

BYPASS FOR
SYSTEM PORT "B"

Y
38.5[1.516]2X

101[3.977]BYPASS FOR SYSTEM PORT "A"

101[3.977]OPTION B
LOOP BYPASS VALVEYBYPASS FOR
SYSTEM PORT "D"

BYPASS FOR SYSTEM PORT "C"

38.5[1.516]2X
169.3[6.665]

P400184

Control Modules
Manula Displacement Control (MDC) Options
R25.4 ±0.2
[1.000 ±.008]
R41.28 ±0.2
[1.625 ±.008]

R32 ±0.2[1.260 ±.008]
R51.8 ±0.2
[2.039 ±.008]

MAX TRAVEL

R50.8 ±0.2
[2.000±.008]

33°
28°

15 N-M MAX[11 FT-LB] MAX

MAX DISPLACEMENTNEUTRALMAX TRAVEL

17 N-M MAX[150 LB-IN] MAX

Pump CL33°
28°

15 N-M MAX[11 FT-LB] MAX
Ø10.00 ±0.12[.394 ±.005]
Ø8.26 ±0.12[.325 ±.005]

28°
33°

MAX DISPLACEMENTNEUTRAL

9.4 ±0.25 185.54[.37 ±.01] [7.305]

MAX TRAVEL

Control handle and spool: code “1”SPECIAL HANDLE

192.86[7.593]7.93 ±0.25[.312 ±.010]
Pump CL

15 N-M MAX[11 FT-LB] MAX

MAX DISPLACEMENT

17 N-M MAX [150 LB-IN] MAX

Control handle and spool: code “3”
STANDARD HANDLE

194.33[7.651]

MAX TRAVEL
R51.8 ±0.2
[2.039 ±.008]

MAX TRAVEL

28°
33° MAX DISPLACEMENT

Ø6.73 ±0.12[.265 ±.005]
3X

R26.4 ±0.2
[1.039 ±.008]

184.08[7.247]

Ø8.26 ±0.12[.325 ±.005]
2X

33°
28°

MAX DISPLACEMENT

28°
33°

MAX DISPLACEMENTMAX TRAVELNEUTRAL

17 N-M MAX [150 LB-IN] MAX

Control handle and spool: code “2”
CLEVIS HANDLE

Pump CL+0.12
7.5 -0.3+.005[.295 -.012 ]195.25[7.687]

P400185© Danfoss | May 2024

BC152886482857en-000306 | 45

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings
CL

144.5
[5.69]
176.4[6.95]

110.3[4.35]

Danfossmating parts
No . K03383(Female Terminals)

A
B

OPTION A,B,X

EXTERNAL BRAKE SUPPLY.5625-18 STR THD O-RING BOSSPER SAE J514
(BRAKE OVERRIDE OPTION ONLY)ELECRIC NEUTRALOVERRIDE AND BRAKE RELEASEFRONT PUMP

Packard Weather-Pack
2-Way Connector(Male Terminals)
Danfossmating parts
Kit No. K26445(Receptacle Terminal)
Deutsch Connector
2-Way connector(Plug Terminal)

50.8[2.00]OVERRIDE TO NEUTRALCONNECTORS

87.4[3.45]

50.8[2.00] 87.4
[3.45]OPTION E,F
NEUTRAL START SWITCHAND BACKUP ALARM

Danfossmating parts
No . K03377(Male Terminals)

A
B

Packard Weather-Pack
2-Way Connector(Female Terminals)
Danfossmating parts
Kit No. K23511(Receptacle Terminal)
Deutsch Connector
4-Way connector(Plug Terminal)

OPTION A, B, C
NEURAL START SWITCHAND/OR BACKUP ALARM

EXTERNAL BRAKE SUPPLY.5625-18 STR THD O-RING BOSSPER SAE J514
(BRAKE OVERRIDE OPTION ONLY)OPTION W, Y
ELECTRICAL NEUTRALOVERRIDE AND BRAKE RELEASEREAR PUMP

274.55[10.81]

176.4[6.95]
Danfossmating parts
Kit No. K26445(Receptacle Terminal)

144.5[5.69]

Deutsch Connector
2-Way connector(Plug Terminal)
CL

NEUTRAL START SWITCH AND
BACKUP ALARM CONNECTORS

46 | © Danfoss | May 2024

OPTION A, L, X
MANUAL DISPLACEMENT CONTROL

P400185

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings
Auxiliary Mounting Pads

MIN 17.5 [0.69]

O-RING SEAL REQUIREDREF 82.22[3.237] I.D. X
2.62[0.103] CROSS SECTIONSPLINE106.38[4.188]

Ø88.65[3.490]R0.38 MAX
[0.015]

4X / -16 UNC - 2B Thd
18 [0.71] MIN Full Thd Depth+0.08
Ø82.6 0+.003
[3.252]03 8106.38[4.188]1.96[0.077]7.37[0.29]MOUNITING
FLANGE44[1.73]MAX SHAFT DEPTH

421.31[16.587]

P400187

Auxiliary mounting flange and coupling options
Auxiliary mounting flange

Spline pitch diameter P

Number of teeth N

Option J

14.288 [0.563] 16/32

9 tooth

Option K

17.463 [0.688] 16/32

11 tooth

Option S

20.638 [0.813] 16/32

13 tooth

MIN 19.7 [0.78]

O-RING SEAL REQUIREDREF 101.27 [3.987] I.D. X
2.62 [0.103] CROSS SECTIONSPLINEØ107.82[4.245]
R0.38 MAX
[0.015]146.05[5.75]+0.07
Ø101.65 0

1.96[0.077]+.003[4.002 0]10.67[0.42]

2X / -13 UNC - 2B Thd
18 [0.71] MIN Full Thd Depth
1 2

MOUNITING
FLANGE46[1.81]MAX SHAFT DEPTH

434[17.087]
P400188

Auxiliary mounting flange and coupling options© Danfoss | May 2024

Auxiliary mounting flange

Spline pitch diameter P

Number of teeth N

Option L

20.638 [0.813] 16/32

13 toothBC152886482857en-000306 | 47

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Installation Drawings

MOUNTING FLANGE
393.5 [15.49]
P400189

Auxiliary mounting flange and coupling options
Auxiliary mounting flange

Spline pitch diameter P

Number of teeth N

Option Q--

MIN 19.7 [0.78]
O-RING SEAL REQUIREDREF 101.27 [3.987] I.D. X
2.62 [0.103] CROSS SECTIONSPLINEØ107.89[4.248]

R0.5
MAX
MOUNTING
FLANGEØ101.69 ±0.038[4.004 ±.001]
1.96[0.077]146[5.748]2X Ø14.4 [0.57]

43.44[1.71]MAX SHAFT DEPTH

409[16.102]
P400190

Auxiliary mounting flange and coupling options

48 | © Danfoss | May 2024

Auxiliary mounting flange

Spline pitch diameter P

Number of teeth N

Option R

20.638 [0.813] 16/32

13 toothBC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Model CodeModel Code: A, Y, Z

Product Series
Code

Description-

4T axial piston pumps

A - Rotation
Code

Description

L

Pump, variable displacement, CCW rotation

R

Pump, variable displacement, CW rotation

Y, Z - Displacement© Danfoss | May 2024

Codecm3/rev [in3/rev]

Speed Sensing

41 BN

41cc/revolution (2.50 CU. IN.) x 2

none

51 DN

51cc/revolution (3.11 CU. IN.) x 2

none

BC152886482857en-000306 | 49

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Model CodeModel Code: FD, FX, RD, RX

FD, FX, RD, RX - Control Type
Control Type

Control Description

Manual Displacement

Neutral Start Switch

X = MDC, LIN, NAR DB, HF
A = MDC, LIN, LF
L = MDC, LIN, NAR DB, LF(Requires Engineering
Approval)BAS(only) with CW handle
rotation:
A = Weather
BAS(only) with CCW handle
rotation:
B = Weather
NSS(only) :C = DEUTSCH
NSS+BAS with CW handle
rotation:
E = DEUTSCH
NSS+BAS with CCW handle
rotation:F = DEUTSCH
N = none

Control Type
Non-Feedback
proportional
G = NFP50 | © Danfoss | May 2024

Control Features

Override to Neutral

Control Handle and Spool

Integral nor with brakerelease in front control:
B = 12V, Deutsch
X = 12V, Weather
Stand Alone nor (front):
A = 24V, DEUTSCH
Integral nor with brakerelease in front control:
W = 12V, Weather
Y = 24V, Deutsch
N = none

1 = Special handle withhigh gain spool
2 = Clevis handle with highgain spool
3 = STD handle with highgain spool
N = No handle

Control Description
Style
3 = HydraulicControl Features
Input

N = Not Available

Other feature
X = Not Available

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Model CodeModel Code: FE, RE(= Standard,= Optional)

FE, RE - Control Response Time
Code

Description

41

51

41

51

MDC
00=

Fast (No Orifice)02=

Medium

03=

Slow

Code

Description

50=

No Orifice

52=

Medium, 1mm

53=Slow, 0.8mm

55=

Fast, Special 1.3mm

NFPH CONTROLS© Danfoss | May 2024

BC152886482857en-000306 | 51

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Model CodeModel Code: FT, RT, FH, RH, FJ, RJ, FK, RK(= Standard,= Optional)

FT, RT - Special Drive Features
Code

Description

N

None

1

NFPH

41

51

41

51

FH, RH - System Pressure Protection Port A and C
CodeDescription

NN

None (Check Valve Only)

21

210 bar (3045 psi)

25

250 bar (3625 psi)

28

280 bar (4060 psi)

30

300 bar (4350 psi)

32

325 bar (4715 psi)

34345 bar (5000 psi)

36

360 bar (5220 psi)-

38385 bar (5585 psi)-

41415 bar (6020 psi)-

FJ, RJ - System Pressure Protection Port B and D
CodeDescription

41

51

NN

None (Check Valve Only)

21

210 bar (3045 psi)

25

250 bar (3625 psi)

28

280 bar (4060 psi)

30

300 bar (4350 psi)

32

325 bar (4715 psi)

34345 bar (5000 psi)

36

360 bar (5220 psi)-

38385 bar (5585 psi)-

41415 bar (6020 psi)-

FK, RK - Loop Bypass Valve52 | © Danfoss | May 2024

Code

Description

N

None

B

Bypass Valve

41

51

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Model CodeModel Code: FL, RL, FM. RM(= Standard,= Optional)

FL, RL - Displacement Limiters Side 1
CodeDescription

41

51

41

51

41

51

41

51

MDC
N

None

A

Adjustable limiters set to max. displacement

B

Adjustable limiters set to 96% of max. displacement

C

Adjustable limiters set to 92% of max. displacement

D

Adjustable limiters set to 88% of max. displacement

E

Adjustable limiters set to 84% of max. displacement

F

Adjustable limiters set to 80% of max. displacement

Code

Description

0

None

1

Adjustable limiters set to max. displacement

2

Adjustable limiters set to 96% of max. displacement

3

Adjustable limiters set to 92% of max. displacement

4

Adjustable limiters set to 88% of max. displacement

5

Adjustable limiters set to 84% of max. displacement

6

Adjustable limiters set to 80% of max. displacement

NFPH Control

FM, RM - Displacement limiters Side 2
CodeDescription

N

None

A

Adjustable limiters set to max. displacement

B

Adjustable limiters set to 96% of max. displacement

C

Adjustable limiters set to 92% of max. displacement

D

Adjustable limiters set to 88% of max. displacement

E

Adjustable limiters set to 84% of max. displacement

F

Adjustable limiters set to 80% of max. displacement

Code

Description

0

None

1

Adjustable limiters set to max. displacement

2

Adjustable limiters set to 96% of max. displacement

3

Adjustable limiters set to 92% of max. displacement

MDC

NFPH Control© Danfoss | May 2024

BC152886482857en-000306 | 53

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Model Code54 | © Danfoss | May 2024

Code

Description

4

Adjustable limiters set to 88% of max. displacement

5

Adjustable limiters set to 84% of max. displacement

6

Adjustable limiters set to 80% of max. displacement

41

51

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Model CodeModel Code: C, F, S(

= Standard,= Optional)

C - Shaft
Code

DescriptionD

15 teeth 16/32 pitchE

19 teeth 16/32 pitch

41

51

41

51

41

51

F - Housing
Code

Description

3

MDC - Standard

5

NFPH - Standard

S - Charge Pressure Relief Setting© Danfoss | May 2024

Code

Description

C

14 bar (203 psi)D

16 bar (232 psi)E

18 bar (261 psi)F

20 bar (290 psi)G

22 bar (319 psi)H

24 bar (348 psi)

N

None

P

DefeatedR

14 bar (203 psi), Anti-stallT

16 bar (232 psi), Anti-stallV

18 bar (261 psi), Anti-stallW

20 bar (290 psi), Anti-stallX

22 bar (319 psi), Anti-stallZ

24 bar (348 psi), Anti-stall

BC152886482857en-000306 | 55

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Model CodeModel Code: U, G, V(

= Standard,= Optional)

U - Auxiliary Mounting Pad
Code

Description

D

Rev B-Pad-Special, 90 and 270 deg gear pump orient, 11 tooth, ship
cover

E

Rev B-Pad, 0 and 180 deg gear pump orient, 13 tooth, ship coverJ

SAE A 9T, All gear pump orientations, ship coverK

SAE A 11T, All gear pump orientations, ship coverL

SAE B 13T, 0 and 180 deg gear pump orientations, ship coverQ

AUX Pad-none, 4T (U000Q)S

AUX Pad-SAE A 13T, Ship cover, 4T (U000S)RSAE B, 13T, 0 and 180 deg gear pump orientations, ship coverT

Rev B-Pad-Special, 90 and 270 deg gear pump orient, 13 tooth, ship
cover

41

51

41

51

41

51

G - Gear Pump
Code

Description

N

None

V - Gear Pump Orientation

56 | © Danfoss | May 2024

Code

DescriptionN

Not Applicable

BC152886482857en-000306

Technical Information
Series 42 4T Axial Piston Tandem Pumps Size 41/51
Model CodeModel Code: N, P(

= Standard,= Optional)

N - Special Hardware
Code

Description

NNR

None, CW rotation

NNL

None, CCW rotation

41

51

P - Special Feature Description (Non-Hardware)
Code

Tag Text Layout

N - Black N(Standard)© Danfoss | May 2024

Tag/
Logo

Line 1

Line 2

Line 3

Line 4

Line 5

Order code
(Standard)

Order code

Order code

Model #

Model #

NDanfoss
Logo

BC152886482857en-000306 | 57

Products we offer:

•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•

Cartridge valves
DCV directional control
valvesElectric converters
Electric machines

Danfoss Power Solutions is a global manufacturer and supplier of high-quality hydraulic andelectric components. We specialize in providing state-of-the-art technology and solutions
that excel in the harsh operating conditions of the mobile off-highway market as well as themarine sector. Building on our extensive applications expertise, we work closely with you toensure exceptional performance for a broad range of applications. We help you and othercustomers around the world speed up system development, reduce costs and bring vehicles
and vessels to market faster.

Gear motors

Danfoss Power Solutions – your strongest partner in mobile hydraulics and mobile
electrification.

Gear pumps

Go to www.danfoss.com for further product information.

Hydraulic integrated
circuits (HICs)
Hydrostatic motors

We offer you expert worldwide support for ensuring the best possible solutions foroutstanding performance. And with an extensive network of Global Service Partners, we also
provide you with comprehensive global service for all of our components.

Electric motors

Hydrostatic pumps
Orbital motors
PLUS+1® controllers
PLUS+1® displays
PLUS+1® joysticks andpedals
PLUS+1® operator
interfaces
PLUS+1® sensors
PLUS+1® software
PLUS+1® software services,support and training
Position controls andsensors
PVG proportional valves
Steering components andsystems
Telematics

Local address:

Hydro-Gear
www.hydro-gear.com
Daikin-Sauer-Danfoss
www.daikin-sauer-danfoss.com

Danfoss
Power Solutions (US) Company
2800 East 13th Street
Ames, IA 50010, USA
Phone: +1 515 239 6000

Danfoss
Power Solutions GmbH & Co. OHG
Krokamp 35
D-24539 Neumünster, Germany
Phone: +49 4321 871 0

Danfoss
Power Solutions ApS
Nordborgvej 81
DK-6430 Nordborg, Denmark
Phone: +45 7488 2222

Danfoss
Power Solutions Trading(Shanghai) Co., Ltd.
Building #22, No. 1000 Jin Hai Rd
Jin Qiao, Pudong New District
Shanghai, China 201206
Phone: +86 21 2080 6201

Danfoss can accept no responsibility for possible errors in catalogues, brochures and other printed material. Danfoss reserves the right to alter its products without notice. This also applies to products
already on order provided that such alterations can be made without subsequent changes being necessary in specifications already agreed.
All trademarks in this material are property of the respective companies. Danfoss and the Danfoss logotype are trademarks of Danfoss A/S. All rights reserved.

© Danfoss | May 2024

BC152886482857en-000306