Technical Information

Series 40 Direct Displacement Pumps

www.danfoss.com

Technical Information
Series 40 Direct Displacement Pumps

Revision history

2 | © Danfoss | July 2024

Table of revisions
Date

ChangedRev

July 2024

Changed document number from 'BC00000106' and '520L0635' to 'BC152886483301'
removed reference to M25

0801

July 2017

Removed outdated images

0703

January 2017

Minor updates

0702

July 2015

Minor edits

0701

February 2015 Danfoss layoutGA

Sep 2013

Change system pressure specs

FB

Aug 2013

Remove M46 from manualFA

Feb 2010

Fix Osaka address

EI

Jun 2009

Remove M25U outline drawing

EH

Jul 2008

Add plug for Charge pressure construction portEG

Oct 2007

Identified A Pad and B Pad as M35 and M44

EF

Jul 2007

orrections to table - G factors for sample applications

ED

Jun 2006

Corrections to maximum flowEC

May 2006

Added an illustration to page 21

EB

BC152886483301en-000801

Technical Information
Series 40 Direct Displacement Pumps
Contents
Specifications
Design Specifications......................................................................................................................................................................5
Technical Specifications.................................................................................................................................................................5
Operating Parameters.....................................................................................................................................................................5
Options.................................................................................................................................................................................................5
Fluid Specifications..........................................................................................................................................................................6
General Information
Series 40 Family of Pumps and Motors.....................................................................................................................................7
M35 Variable Pump (M44 is similar)...........................................................................................................................................7
M35/44 Pump Schematic.............................................................................................................................................................. 8
Features and Options
Key Features....................................................................................................................................................................................... 9
Options.................................................................................................................................................................................................9
Operating Parameters
Fluids.................................................................................................................................................................................................. 10
Viscosity.............................................................................................................................................................................................10
Temperature.................................................................................................................................................................................... 10
Charge Pressure..............................................................................................................................................................................10
Case Pressure...................................................................................................................................................................................10
Pressure Ratings............................................................................................................................................................................. 11
Speed Ratings..................................................................................................................................................................................11
Inlet Pressure................................................................................................................................................................................... 11
Theoretical Output........................................................................................................................................................................ 12
System Design Parameters
Sizing Equations............................................................................................................................................................................. 13
Filtration............................................................................................................................................................................................ 13
Suction filtration....................................................................................................................................................................... 13
Charge filtration........................................................................................................................................................................ 14
Redundant Braking System Requirement.............................................................................................................................14
Loop Flushing..................................................................................................................................................................................15
Reservoir............................................................................................................................................................................................15
Case Drain usage for Tandem Pumps.....................................................................................................................................15
Bearing Life and External Shaft Loading ...............................................................................................................................15
Hydraulic Unit Life......................................................................................................................................................................... 16
Mounting Flange Loads...............................................................................................................................................................17
Model CodeModel Code......................................................................................................................................................................................19
Options
Charge Pump...................................................................................................................................................................................21
Charge Pump Output Flow........................................................................................................................................................ 22
Charge Pump Power Requirements........................................................................................................................................22
Charge Relief Valve........................................................................................................................................................................22
Charge Check/High Pressure Relief Valve (HPRV).............................................................................................................. 23
Auxiliary Mounting Pads and Auxiliary Pumps................................................................................................................... 24
Shaft Options...................................................................................................................................................................................26
M35/44 Variable Pump................................................................................................................................................................ 27
M35/44 Tandem Pump................................................................................................................................................................ 28
Direct Displacement Control (DDC)........................................................................................................................................ 29
External control handle requirements..............................................................................................................................29
Installation Drawings
M35/44 Variable Pump................................................................................................................................................................ 31
M35/44 Tandem Pump................................................................................................................................................................ 33
Performance Data
Performance.....................................................................................................................................................................................37© Danfoss | July 2024

BC152886483301en-000801 | 3

Technical Information
Series 40 Direct Displacement Pumps
Contents
Schematics
Single Pump Schematics............................................................................................................................................................. 38
Tandem Pump Schematics.........................................................................................................................................................38

4 | © Danfoss | July 2024

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Technical Information
Series 40 Direct Displacement Pumps
Specifications
Design Specifications
Product line

Series 40 Pumps

Pump typeIn-line, axial piston, variable, positive displacement pumps

Direction rotation

Clockwise (CW) or counterclockwise (CCW) available

Installation position

Discretionary, the housing must be filled with hydraulic fluid

Filtration configuration

Suction or charge pressure filtration

Other system requirements

Independent braking system, suitable reservoir and heat exchanger

Technical Specifications
Model

Unit

M35 PV

Single variable pumpTandem variable pump

Displacement

cm3/rev [in3/rev]

35.0 [2.14]

35.0 x 2[2.14 x 2]

Weightkg [lb]25 [55]25 [55]45 [99]45 [99]Mass moment ofinertiakg·m2 [slug·ft2] 0.0033[0.0024]0.0032[0.0023]

0.0066[0.0048]0.0064[0.0047]

Pump configuration

M44 PV

M35 PT

43.5 [2.65]

M44 PT

43.5 x 2[2.65 x 2]

Operating Parameters
Model

Unit

M35 PV

M44 PV

M35 PT

M44 PT

Continuousbar [psi]

1.7 [25]

Maximumbar [psi]

5.2 [75]

Rated @ max angle

min-1 (rpm)3600

Maximim @ max angle

min-1 (rpm)

3300

3600

3300

4500

4100

4500

4100

Minimummin-1 (rpm)

500

500

500

500

Maximum Working

bar [psi]

380 [5511]

345 [5000]

380 [5511]

345 [5000]

Maximumbar [psi]

415 [6019]

415 [6019]

415 [6019]

415 [6019]

Theoretical max flow at rated
speed (per pump)l/min[US gal/min]

126[33.4]

145[38.3]

126[33.4]

145[38.3]

Continuous

bar absolute[in Hg vacuum]

0.8 [6.3]

Maximumbar absolute[in Hg vacuum]

0.7 [9.2]

Model

Unit

Case pressure

Speed limits

System pressure

Inlet pressure

Options

Type of mounting
Port connections
Integral charge pump (std)© Danfoss | July 2024

cm3/rev [in3/rev]

M35 PV

M44 PV

M35 PT

M44 PT

SAE B

SAE B

SAE B

SAE B

Twin

Twin

Twin

Twin

11.8
[0.72]

11.8[0.72]

16.4[1.00]

16.4[1.00]BC152886483301en-000801 | 5

Technical Information
Series 40 Direct Displacement Pumps
Specifications
Model

Unit

M35 PV

M44 PV

M35 PT

M44 PT

Charge relief valve setting

bar [psi]

14.0
[200]

14.0
[200]

14.0
[200]

14.0
[200]

System pressure regulation

bar [psi]

140-345 [2030-5000]--

Displacement limiters-

Input shaft option

Splined, Tapered, or Straight Key-

Auxiliary mounting pad

SAE A
SAE B

SAE A
SAE B

SAE A
SAE B

SAE A
SAE B

Control options

DDC

DDC

DDC

DDC

Filtration configuration

Suction Filtration or Remote Charge Pressure Filtration

Fluid Specifications
Parameter

Unit

Minimum

Continuous

Maximum

Viscosity

mm2/sec (cSt)
[SUS]

7
[47]

12-60
[70-278]1600[7500]

Temperature°C [°F]-40 [-40]

82 [180]

104 [220]

ISO 4406 Class 18/13 or better

Cleanliness
Filtration efficiency

suction filtration

β35-44=75 (β10≥1.5)

charge filtration

β15-20=75 (β10≥10)

Ratings and data are based on operation with premium petroleum-based hydraulic fluids containing
oxidation, rust, and foam inhibitors.

6 | © Danfoss | July 2024

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Technical Information
Series 40 Direct Displacement Pumps
General Information
Series 40 Family of Pumps and Motors
Series 40 is a family of hydrostatic pumps and motors for medium power applications with maximum
loads of 345 bar [5000 psi]. These pumps and motors can be applied together or combined with otherproducts in a system to transfer and control hydraulic power.
Series 40 pump + motor transmissions provide an infinitely variable speed range between zero andmaximum in both forward and reverse modes of operation. The pumps and motors each come in threeframe sizes: M35, M44, and M46.
Series 40 pumps are compact, high power density units. All models use the parallel axial piston / slipper
concept in conjunction with a tiltable swashplate to vary the pump’s displacement. Reversing the angleof the swashplate reverses the flow of fluid from the pump, reversing the direction of rotation of the
motor output.
Series 40 - M35 and M44 pumps may include an integral charge pump to provide system replenishingand cooling fluid flow. Series 40 pumps feature a range of auxiliary mounting pads to accept auxiliary
hydraulic pumps for use in complementary hydraulic systems.
For complete technical information on M46 pumps, refer to M46 Pumps Technical Information, L1001029.
Series 40 motors use the parallel axial piston/slipper design in conjunction with a fixed or tiltableswashplate. The family includes M35, M44 fixed motor units and M35, M44, M46 variable motor units. For
complete technical information on Series 40 motors, refer to Series 40 Motors Technical Information,
BC152886483445.
The M35 and M44 variable motors feature a trunnion style swashplate and direct displacement control.
The M46 variable motors use a cradle swashplate design and a two-position hydraulic servo control.
The M46 variable motor is available in a cartridge flange version, which is designed to be compatible with
CW and CT compact planetary gearboxes. This combination provides a short final drive length forapplications with space limitations.
M35 Variable Pump (M44 is similar)
Charge check andhigh pressure relief
valve with bypass

Charge relief
valve

Valve plat e
PistonChargepum p

Ballbearing

Auxiliarypad

Trunnion

Input
shaft

Cylinderblock

Swashplate
P100 584E

A variable pump is shown in a hydraulic circuit with a fixed motor. The pump shown features manual
displacement control. The circuit features suction filtration and heat exchanger.

© Danfoss | July 2024

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Technical Information
Series 40 Direct Displacement Pumps
General Information
M35/44 Pump Schematic
Remote pressure filtration(no charge pump)
Remote Pressure Filtration
E

E

D
Suction Filtration
E M3
L2
A
M1

M2
B
L1

No relief valve

S
P100 638E

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Technical Information
Series 40 Direct Displacement Pumps
Features and Options
Key Features

•
•
•
•
•
•
•
•

3 sizes of variable displacement pumps
3 sizes of tandem pumps
3 sizes of variable displacement motors
2 sizes of fixed displacement motors
Efficient axial piston design
Proven reliability and performance
Compact, lightweightWorldwide sales and service

Options
High Pressure Relief Valve (HPRV) - A high pressure relief valve limits the system pressure to protect
the system from over-pressure.
Charge Relief Valve - The charge pressure relief valve regulates charge pressure.
Displacement Limiters - Optional displacement limiters allow maximum displacement adjustment toallow for fine tuning of the propel system.
Auxiliary Mounting Pads - Several auxiliary mounting pad options allow for adding a second pump.
Input Shafts - Straight keyed, tapered keyed, and several splined shaft options are available.

© Danfoss | July 2024

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Technical Information
Series 40 Direct Displacement Pumps
Operating Parameters
FluidsRatings and performance data are based on operating with premium hydraulic fluids containing
oxidation, rust, and foam inhibitors. These include premium turbine oils, API CD engine oils per SAE J183,
M2C33F or G automatic transmission fluids (ATF), Dexron II (ATF) meeting Allison C-3 or Caterpillar T0‑2
requirements, and certain specialty agricultural tractor fluids. For more information on hydraulic fluid
selection, see Danfoss publications: Hydraulic Fluids and Lubricants, Technical Information,
BC152886484524 and, Experience with Biodegradable Hydraulic Fluids, Technical Information,520L465.
Viscosity
Maintain fluid viscosity within the recommended range for maximum efficiency and bearing life.
Minimum viscosity is acceptable only during brief occasions of maximum ambient temperature andsevere duty cycle. Maximum viscosity is acceptable only at cold start: Limit speeds until the system warms
up. See Danfoss publications: Hydraulic Fluids and Lubricants, Technical Information, BC152886484524,
and Experience with Biodegradable Hydraulic Fluids, Technical Information, 520L465.
Fluid viscosity limits
Condition

mm2/s (cSt)SUSMinimum

7

47

Continuous

12-60

70-278Maximum

1600

7500

Temperature
Maintain fluid temperature within the limits shown in the table. Minimum temperature relates to thephysical properties of the component materials. Cold oil will not affect the durability of the motor
components. However, it may affect the ability of the motor to transmit power. Maximum temperature
is based on material properties: Don’t exceed it. Measure maximum temperature at the hottest point in
the system. This is usually the case drain.
Ensure fluid temperature and viscosity limits are concurrently satisfied.
Temperature limits
Minimum (intermittent, cold start)- 40° C [- 40° F]

Continuous

82.2° C [180° F]

Maximum

104.4° C [220° F]

Charge Pressure
All systems require a charge (positive pressure) in the low side of the system loop for proper lubrication
and rotating group operation. Maintain low loop (charge) pressure at a minimum of 6 bar [87 psi] abovecase pressure.
Case Pressure
Maintain case pressure within the limits shown in the table. Ensure housing is filled with hydraulic fluid.
Case pressure limits

10 | © Danfoss | July 2024

Maximum (continuous)

1.7 bar [25 psi]

Intermittent (cold start)

5.2 bar [75 psi]

BC152886483301en-000801

Technical Information
Series 40 Direct Displacement Pumps
Operating Parameters

C Caution
Operating outside of charge and case pressure limits will damage the pump. To minimize this risk, use fullsize inlet and case drain plumbing, and limit line lengths.

Pressure Ratings
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 proper component 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 low loop pressure must be maintained under all operating conditions to avoid cavitation.
All pressure limits are differential pressures referenced to low loop (charge) pressure. Subtract low looppressure from gauge readings to compute the differential.

Speed Ratings
The table, Operating Parameters in the Specifications section, gives rated and maximum speeds for eachdisplacement. Not all displacements operate under the same speed limits. Definitions of these speed
limits appear below.
Continuous speed is the maximum recommended operating speed at full power condition. Operating ator below this speed should yield satisfactory product life. Do not exceed maximum motor speed during
unloaded, on-road travel over level ground.
Maximum speed is the highest operating speed permitted. Exceeding maximum speed reduces pumplife and can cause loss of hydrostatic power and braking capacity. Never exceed the maximum speed
limit under any operating conditions.

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 thehydrostatic transmission, sufficient to stop and hold the vehicle or machine in the event of hydrostatic
drive power loss.

Inlet Pressure
Achieving acceptable pump life and performance requires proper charge pump inlet design. A
continuous inlet pressure of not less than 0.8 bar abs. (not more than 6.3 in. Hg vac.) is recommended.
Normal pressure less than the minimum inlet pressure of 0.7 bar abs. (greater than 9.2 in. Hg vac.)indicates inadequate inlet design or a restricted filter. Pressures less than 0.7 bar abs. (greater than 9.2 in.
Hg vac.) during cold start are possible, but should improve quickly as the fluid warms.

© Danfoss | July 2024

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Technical Information
Series 40 Direct Displacement Pumps
Operating Parameters
Inlet pressure
bar absolutein. Hg vacuum

Continuous

0.8

6

Minimum

0.7

9.2 (max)

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.

12 | © Danfoss | July 2024

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Technical Information
Series 40 Direct Displacement Pumps
System Design 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]
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)
Filtration
Ensure fluid entering pump is free of contaminants to prevent damage (including premature wear) to thesystem. Series 40 pumps require system filtration capable of maintaining fluid cleanliness at ISO
4406-1999 class 22/18/13 or better.
Consider these factors when selecting a system filter:
Cleanliness specifications

•
•
•
•

Contaminant ingression rates
Flow capacity
Desired maintenance interval

Locate filter either on the inlet (suction filtration) or discharge (charge pressure filtration) side of thecharge pump. Series 40 pumps are available with provisions for either strategy.
Typically, a filter with a beta ratio of β10 = 1.5 to 2.0 is adequate. However, open circuit systems supplied
from a common reservoir may have considerably higher requirements. Because each system is unique,only a thorough testing and evaluation program can fully validate the filtration system. For more
information, see Danfoss publication Design Guidelines for Hydraulic Fluid Cleanliness, BC152886482150.
Suction filtration
The suction filter is placed in the circuit between the reservoir and the inlet to the charge pump as shownin the accompanying illustration.

© Danfoss | July 2024

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Technical Information
Series 40 Direct Displacement Pumps
System Design Parameters
Suction filtration

FilterStrainer
Reservoir

To low pressure
side of loop
and ser vo contro l

Charge relief
valveChargepump

To pump case

P100 588E

Charge filtration
Provision for charge pressure filtration is available on all Series 40 pumps. The pressure filter is remotely
mounted in the circuit after the charge pump, as shown in the accompanying illustration.
Filters used in charge pressure filtration circuits must be rated to at least 34.5 bar [500 psi] pressure. A 100- 125 µm screen located in the reservoir or in the charge inlet line is recommended when using chargepressure filtration.
A filter bypass valve is necessary to prevent filter damage and to avoid contaminants from being forced
through the filter media by high pressure differentials across the filter. In the event of high pressure drop
associated with a blocked filter or cold start-up conditions, fluid will bypass the filter. Avoid working with
an open bypass for an extended period. We recommend a visual or electrical bypass indicator. Proper
filter maintenance is mandatory.
Charge filtration

Reservoir

Strainer

Filterwith bypass

To Low Pressur eside of loop
and ser vo contro l

Charge relief
valveChargepump
To pump case
P106 102E

Redundant Braking System Requirement

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 thehydrostatic transmission, sufficient to stop and hold the vehicle or machine in the event of hydrostatic
drive power loss.
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Technical Information
Series 40 Direct Displacement Pumps
System Design Parameters
Loop Flushing
Closed circuit systems may require loop flushing to meet temperature and cleanliness requirements. A
loop flushing valve removes hot fluid from the low pressure side of the system loop for additional coolingand filtering. Ensure the charge pump provides adequate flow for loop flushing and the loop flushingvalve does not cause charge pressure to drop below recommended limits.
Reservoir
The reservoir provides clean fluid, dissipates heat, and removes entrained air from the hydraulic fluid. It
allows for fluid volume changes associated with fluid expansion and cylinder differential volumes.
Minimum reservoir capacity depends on the volume needed to perform these functions. Typically, acapacity of one half the charge pump flow (per minute) is satisfactory for a closed reservoir. Open circuit
systems sharing a common reservoir require greater fluid capacity.
Locate the reservoir outlet (suction line) near the bottom, allowing clearance for settling foreign particles.
Use a 100 - 125 µm screen covering the outlet port.
Place the reservoir inlet (return lines) below the lowest expected fluid level, as far away from the outlet as
possible.
Use a baffle (or baffles) between the reservoir inlet and outlet ports to promote de-aeration and reduce
fluid surging.
Case Drain usage for Tandem Pumps
On tandem pumps, excess flow from the charge relief valve is routed into the housing of the front pump.
In order to ensure adequate case flushing, it is recommended that the rear housing drain ports be used as
the case drain.
M43/M44 tandem pumps with the option of opposing port endcaps do not follow the above rule.

Bearing Life and External Shaft Loading
Bearing life is a function of speed, pressure and swashplate angle plus any external loads. Other life
factors include oil type and viscosity.
In vehicle propulsion drives with no external loads, where the speed, pressure, and swashplate angle areoften changing, normal bearing B10 (90% survival) life will exceed 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, a bearing life review is recommended.
Series 40 pumps are designed with bearings that can accept some incidental external radial and thrustloads. However, any amount of external load will reduce the expected bearing life.
The allowable radial shaft loads are a function of the load position, the load orientation, and theoperating pressures of the hydraulic unit. All external shaft loads have an effect on bearing life. In
applications where external shaft loads cannot be avoided, the impact on bearing life can be minimized
by orienting the load to the 90 or 270 degree position.
The maximum allowable radial loads (Re), based on the maximum external moment (Me) and the
distance (L) from the mounting flange to the load, may be determined from the tables below anddrawings on the next page .
The maximum allowable radial load is calculated as: Re = Me / L
Avoid thrust loads in either direction.
If continuously applied external radial loads are 25% or more of the maximum allowable, or thrust loads
are known to occur, contact your Danfoss representative for an evaluation of unit bearing life. Optional
high capacity bearings are available.
© Danfoss | July 2024

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Technical Information
Series 40 Direct Displacement Pumps
System Design Parameters
Tapered output shafts or clamp-type couplings are recommended for applications where radial shaft sideloads are present.
Shaft loading parameters
Re

Maximum radial load

Me

Maximum external moment

L

Distance from mounting flange to point of load

Fe

Force of cylinder blockTe

Thrust load

Maximum external shaft moments
M35/44
Me/N•m [in·lbf]

121 [1075]

180° External radial shaft load

FBL

Fb 0 Re

Re

CW

CCW

Te

270 Re90 Re

180 ReP100 594E

Direction of external shaft load

0 Re
End viewof shaft

90 Re

Axis of swashplate
rotation

270 Re180 ReP100 595E

Hydraulic Unit Life
Hydraulic unit life is defined as the life expectancy of the hydraulic components. It 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.
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Technical Information
Series 40 Direct Displacement Pumps
System Design Parameters
All pressure limits are differential pressures (referenced to charge pressure) and assume normal chargepressure.
Series 40 pumps will meet satisfactory life expectancy if applied within the parameters specified in thisbulletin. For more detailed information on hydraulic unit life see Pressure and Speed Limits,
BC152886484313.
Mounting Flange Loads
Shock load moment is the result of an instantaneous jolt to the system. Continuous load moments are
generated by the typical vibratory movement of the application. Avoid excessive loading of themounting flange such as adding tandem mounted auxiliary pumps and/or subjecting pumps to highshock loads. Design pump applications to stay within the allowable shock load moment and allowablecontinuous load moment.
Use the following formulas to estimate overhung load moment for multiple pump mountings:
MS = GS (W1L1 + W2L2 + ... +WnLn)
MC = GC (W1L1 + W2L2 + ... +WnLn)
Refer to the Installation Drawings section to find pump length (L). Refer to the table Technical
Specifications in the Specifications section, to find pump weight (W). An exact measure of W will dependon the pump’s features.
The tables below show allowable overhung load moment values. If system parameters exceed thesevalues add additional pump support.
Estimated maximum and continuous acceleration factors for some typical Series 40 applications areshown. Applications which experience extreme resonant vibrations may require additional pumpsupport. Typical continuous (vibratory) values can vary significantly due to changes in engine and pumpconfiguration and mounting methods.
Overhung loading parameters
Ms

Shock load moment

Mc

Continuous load moment

Gs

Maximum shock acceleration (Gs)GcContinuous (vibratory) acceleration (Gs)

Wn

Weight of nth pump

Ln

Distance from mounting flange to center of gravity of nth pump

Allowable overhung parameters
Frame size

Continuous load moment (Mc)N•m [in·lbf]

Shock load moment (Ms)N•m [in·lbf]

M35 PV

517[4600]

832[7400]

M35 PT

517[4600]

754[6700]

Shaft loading parameters
CG
Pump 2CG
Pump 1

L2

Mountingflange

L1
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Technical Information
Series 40 Direct Displacement Pumps
System Design Parameters
G-factors for sample applications
Application

Continuous (vibratory)
acceleration (Gc)

Maximum (shock) acceleration(Gs)

Skid steer loader

410Trencher(rubber tires)

3

8Asphalt paver

2

6Windrower

2

5

Aerial lift

1.5

4

Turf care vehicle

1.5

4

Vibratory roller

610* Applications which experience extreme resonant vibrations require addition pump support.

18 | © Danfoss | July 2024

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Technical Information
Series 40 Direct Displacement Pumps
Model CodeModel CodeModel code modules
Displacement

M P

V

0

3

5

C

Product

C D E

F

G

H

J

B

R

A

G

N N

A

A

Type

K L

M

N

P

A

A A

B A

A

A A

R

S

T

B

H

A

N N N

E

F

G

H

J

S

R

A

E

N N

C: Swashplate group
D: Seal group
F: Rotation
E: Input shaft
G: Charge pump displacement
H: Charge pressure relief setting
J: Filtration
K: Displacement limiters
L: Bypass valve
M: System pressure protection
N: Control
P: Control handle position
R: Control orifice diameters
S: Auxiliary mounting pad
T: Special hardware
Model code modules
Displ acemen t

M P

T

0

3

Product

5

C
Type

Front Pump

C
B

D
A

K
A

L
A

M
B D D

N
D L

P
A

F

R

Z
A

F

F

Rear Pump

Q
B

D
C

U
A

S
C

T
N N N

X
A

V
B D D

Y
D R

W
F

E: Input shaft
F: Rotation
G: Charge pump displacement
H: Charge pressure relief setting© Danfoss | July 2024

BC152886483301en-000801 | 19

Technical Information
Series 40 Direct Displacement Pumps
Model Code
J: Filtration
C & Q: Swashplate
D: Seal group
K & U: Displacement
L & X: Bypass valve
N & Y: Control
M & V: System pressure protection
P & Z: Control handle position
R & W: Control orifice
S: Auxiliary mounting flange
T: Special hardware

20 | © Danfoss | July 2024

BC152886483301en-000801

Technical Information
Series 40 Direct Displacement Pumps
Options
Charge Pump
Charge flow is required on all Series 40 units applied in closed circuit installations to make up for internal
leakage, maintain positive pressure in the main circuit, provide flow for cooling, replace any leakage
losses from external valving or auxiliary systems, and on M46 units, to provide flow and pressure for thecontrol system.
Maintain rated charge pressure under all conditions of operation to prevent damage to the transmission.
Charge pump in series 40 - M35 PV

P100 589E

All Series 40 pumps may be equipped with integral charge pumps. These charge pump sizes have been
selected to meet the needs of a majority of Series 40 applications.
Many factors influence the charge flow requirements and the resulting charge pump size selection. These
factors include system pressure, pump speed, pump swashplate angle, type of fluid, temperature, size ofheat exchanger, length and size of hydraulic lines, control response characteristics, auxiliary flow
requirements, hydraulic motor type, etc. In most Series 40 applications a general guideline is that the
charge pump displacement should be equal to or greater than 10% of the total displacement of all units
in the system.
The total charge flow requirement is the sum of the charge flow requirements of each of the components
in the system. Use the information provided on the following pages to make a charge pump selection fora given application.
System features and conditions that may invalidate the 10% of displacement rule include (but are notlimited to):• Operation at low input speeds (below 1500 RPM)

•
•
•
•

Shock loading
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 is available in Selection of Driveline Components, BC157786484430.
Series 40 pumps are also available without charge pumps. When an integral charge pump is not used, anexternal charge supply is required to ensure adequate charge pressure and cooling.

© Danfoss | July 2024

BC152886483301en-000801 | 21

Technical Information
Series 40 Direct Displacement Pumps
Options
Charge Pump Output Flow
Flow at standard charge relief setting, 70°C [160°F] inlet
l/min
90

US Gal/min
24

75

20

60

16

45

12

30

8

15

4

0

0

M35 PT
M35 PV

0

1000

2000

3000

Speed min -1(rpm)4000
T101 302E

Charge Pump Power Requirements
Power at standard charge relief setting, 70°C [160°F] inlet
kW

hp
6

4

5

3

4

2

3

M35PT

2
1
0

M35PV

1
0

0

1000

2000
3000
Speed min -1 (rpm)4000
T101 303E

Charge Relief Valve
An integral charge pressure relief valve provides a relief outlet for charge pressure. This valve, in effect,
sets charge pressure. Flow through the valve is ported to case.
The charge relief valve for the M35 and M44 PV/PT is a flat poppet style valve.
The nominal charge relief setting is referenced to case pressure. It is factory set at 1800 min-1 (rpm) withthe pump in neutral position. A proper charge relief setting takes into account input speeds and control
requirements.
The charge pressure setting for pumps without an internal charge pump is set with an externally suppliedcharge flow of 19 l/min [5 US gal/min] on pumps and 38 l/min [10 US gal/min] on tandem pumps. These
units must have adequate charge flow supplied to the charge inlet in order to maintain charge pressure
at all times.
Incorrect charge pressure settings may result in the inability to build required system pressure and/or
inadequate loop flushing flows. Ensure correct charge pressure under all conditions of operation tomaintain pump control performance.
The charge relief valve is factory set. If necessary, it can be field adjusted with shims.

22 | © Danfoss | July 2024

BC152886483301en-000801

Technical Information
Series 40 Direct Displacement Pumps
Options
Charge relief valve specs
M35
Type

Flat poppet valve

Available setting

6.2-24 bar [90-348 psi]

Adjustment

Via shims inside of valve cartridge*

M44

6.2-28.3 bar [90-410 psi]

* Shimming offers adustment over a limited range, a spring change may be required to make a larger adjustment.

Charge relief valve locations

Charge Relief Valve

M35 & M44 PV

P100 591E

Charge Check/High Pressure Relief Valve (HPRV)Charge check and high pressure relief valves maintain circuit pressure in the proper range. The checkvalves allow charge flow to replenish the low pressure side of the working loop. The high pressure relief
valves provide pressure protection to the high pressure side of the working loop. There are two cartridgestyle valves to handle each side of the working loop with flow in either direction.
High pressure relief valves are available in a range of settings. You may specify individual port pressure
settings . If high pressure relief valves are not desired, pumps may be equipped with charge circuit checkvalves only.

C Caution
High pressure relief valves are intended for transient overpressure protection and are not intended forcontinuous pressure control. Flow over relief valves for extended periods of time may result in severe
heat build up. High flows over relief valves may result in pressure levels exceeding the nominal valve
setting and potential damage to system components.
Check/high relief valve specs© Danfoss | July 2024

Type

Cartridge-style poppet valve

Setting140-345 bar (2030-5000 psi)

OptionCheck only - no relief valve

BC152886483301en-000801 | 23

Technical Information
Series 40 Direct Displacement Pumps
Options
High pressure relief valve locations

High pressure/check valve

M35 & M44PV

P100 590E

Auxiliary Mounting Pads and Auxiliary Pumps
Auxiliary mounting pads are available on all Series 40 pumps. A sealed cover is included as standard
equipment on all mounting pads.
An O-ring seals the auxiliary pump mounting flange to the pad. The drive coupling is lubricated with oilfrom the main pump case.
Spline specifications and torque ratings are shown in the accompanying table.
All auxiliary mounting pads meet SAE J744 specifications.

•••

Do not exceed the maximum pump input shaft rating.
Applications subject to severe vibratory or high G loading require an additional structural support.
This is necessary to prevent leaks and possible mounting flange damage. Refer to Mounting Flange
Loads in the System Design Parameters section for additional information.

Auxiliary mounting pad specs
Internal
spline size

Pad size

9T
16/32P

SAE A

11T
16/32P
13T
16/32P

Torque rating

AvailabilityN•m[in • lbf]

M35

M44

Continuous:
Max:

51
107

[450]
[950]

m

m

SAE A

Continuous:
Max:

90
147

[800]
[1300]

m

m

SAE B

Continuous:
Max:

124
248

[1100][2200]mm

The drawing and table below show the dimensions of the auxiliary pump mounting flanges and shafts.
Auxiliary pump mounting flanges and shafts with the dimensions noted are compatible with the auxiliary
mounting pads on the Series 40 pumps.

24 | © Danfoss | July 2024

BC152886483301en-000801

Technical Information
Series 40 Direct Displacement Pumps
Options
Auxiliary pump mating dimensions mm [in.]
D
max
E
max

F min spline
engagement
for fulltorque rating

Mountingflange (ref )Withundercut
P Dia
Without
undercut

0.8 [0.03] max R
Couplin gBmax

2.3 [0.090]
recommended
cutter clearanc eC
max

P100 636E© Danfoss | July 2024

Pad size

P

B

C

D

E

F

SAE A

82.55
[32.50]6.35[0.250]12.70[0.500]58.2[2.29]

15.0[0.59]

13.5[0.53]

SAE B

101.60[4.000]9.65[0.380]15.2[0.60]

53.1[2.09]

17.5[0.69]

14.2[0.56]BC152886483301en-000801 | 25

Technical Information
Series 40 Direct Displacement Pumps
Options
Auxiliary mounting pads on Series 40 pumps

M35 & M44 PV

A Pad
M35 & M44 PV

B Pad
M35 & M44 PV
P100 593E

Shaft Options
Series 40 pumps are available with a variety of splined, straight keyed, and tapered shaft ends. Nominal
shaft sizes and torque ratings are shown in the table on the next page.
Torque ratings assume no external radial loading. Continuous torque ratings for splined shafts are basedon splined tooth wear, and assume the mating spline has a minimum hardness of Rc 55 and full spline
depth with good lubrication.
Maximum torque ratings are based on shaft torsional strength and assume a maximum of 200,000 load
reversals.
Recommended mating splines for Series 40 splined output shafts should be in accordance withANSIB92.1 Class 5. Danfoss external splines are modified Class 5 Fillet Root Side Fit. The external splined
Major Diameter and Circular Tooth Thickness dimensions are reduced in order to assure a clearance fit
with the mating spline. Other shaft options may exist. Contact your Danfoss representative foravailability.

26 | © Danfoss | July 2024

BC152886483301en-000801

Technical Information
Series 40 Direct Displacement Pumps
Options
M35/44 Variable Pump
Code DescriptionYØ 22.20 mm [0.874 in]
Straight keyed

Torque rating

Drawing

Maximum torqueratingN•m [lbf•in]Continuous torqueratingN•m [lbf•in]

226 [2000]—

6.35 [0.250] sq. key
38.1 [1.500] long
0.38 [0.015] min. R on edges

Mounting flange(ref.)
7.9 [0.31]
Coupling must not
protrude beyond
this surface

AG

13-tooth226 [2000]
16/32 pitch(ANSI B92.1 1970 - Class 5)
15-tooth362 [3200]
16/32 pitch(ANSI B92.1 1970 - Class 5)

124 [1100]
7.9 [0.31]

153 [1350]

Mounting flange(ref)W dia pitch
Y teeth, 16/32
30° pressure angle
fillet root side fit
per ANSI B92.1-1970
class 5
Also mates withflat root side fit

NØ 25.4 mm [1.000 in]
1:8 taper (SAE J501)

497 [4400]

2.85 [0.112] max.
22.2 [0.874] dia.
63.5
[2.50]
P104 409E
Coupling must not protrude
beyond this surface
33.3 [1.31]
U
V
T

P104 410E
42.8 [1.685]—

6.35 [0.250] Sq. key
19.05 [0.75] long
0.38 [0.015] min. R on edges
Mounting flange(ref.)

3/4-16 UNF-2B thd.
2.84 [0.112] max.
22.2 [0.875] Gauge dia.

1.50 in/ft
per SAE
standard J501
25.4 [1.000] Nom
shaft dia.

Coupling must not

protrude beyond
25.4 [1.000] max.

26. 9
[1.06]
33.3 [1.311] Gauge dim.
P104 411E© Danfoss | July 2024

BC152886483301en-000801 | 27

Technical Information
Series 40 Direct Displacement Pumps
Options
M35/44 Tandem Pump
Code Description

Torque rating
Maximum torqueratingN•m [lbf•in]

A

G

Drawing
Continuous torqueratingN•m [lbf•in]

15-tooth362 [3200]
16/32 pitch(ANSI B92.1 1970 - Class 5)

153 [1350]

15-tooth362 [3200]
16/32 pitch(ANSI B92.1 1970 - Class 5)

153 [1350]

Coupling must not protrude
beyond this surface
1.35[0.053]33.3 [1.31]
UVT

7.9 [0.31]
Mounting flange(ref.)

W dia pitch
Y teeth, 16/32
30° pressure angle
fillet root side fit
per ANSI B92.1-1970
class 5
Also mates withflat root side fit

V T

Option A

P104 418E

Full spline

option

T

U

V

W

Y

G

21.97

39.4 [1.55]

24.89

23.81215[0.9800][0.9375]

24.89

23.812[0.9800][0.9375]

21.97

18.5 [0.73][0.865]

Ø 25.4 mm [1.000 in]
1:8 taper (SAE J501)

497 [4400]

Option G

Shaft dia.

[0.865]CU
33.02[1.300]

Shaft

A

—

48.9
[1.925]Major dia.

Pitch dia.

No. teeth15

6.35 [0.250] Sq. key
19.05 [0.75] long
0.38 [0.015] min. R on edges

42.8[1.685]26.9 [1.06]
3/4-16 UNF-2Bth d.

2.84 [0.112]
max.

24.61 [0.969]
max. Shaft dia.

22.22 [0.875] Gauge dia.
38.1 [1.500] taper per footper SAE J501
25.4 [1.000] nominal shaft dia.
except for 24.61 [0.969] dia as shown
coupling must not protrude beyond
25.40 [1.000] max.

Mounting f lange(ref.)

33.3 [1.311]
To gauge di m.

P104 405E

F

14-tooth
12/24 pitch(ANSI B92.1-1996 Class 5)499 [4416]

488 [4416]
0.301 ± 0.017[7.65] ± 0.43

Coupling must not
protrude beyond
this surface
1.935 ± 0.025[49.15] ± 0.5

Mountingflange REF

1.26 ± 0.02
[32.1] ± 0.5
Ø 1.243 ± 0.004[31.57] ± 0.09

Max
Ø 1.013 [25.7]

1.667 [29.634] pitch diameter
30° pressure angle
Fillet root side fit
Also mates with flat root side fit

Input shaft option “F”

28 | © Danfoss | July 2024

BC152886483301en-000801

Technical Information
Series 40 Direct Displacement Pumps
Options
Direct Displacement Control (DDC)
The Direct Displacement Control (DDC) can be located on either side of a Series 40 - M35, or M44 pump. It
provides a simple, positive method of control. Movement of the control shaft causes a proportionalswashplate movement, thus varying the pump’s displacement from full displacement in one direction to
full displacement in the opposite direction.
Some applications (generally vehicle propel) require a provision for non-linear control input to reduce
control sensitivity near neutral. Damping or frictional forces may be necessary to produce desirable
control feel.
Neutral position is not factory set, nor is there any internal neutral return mechanism. The applicationmust include provisions for all control linkage and neutral return fuctionality.
With no external forces applied to the swashplate trunnion, internal hydraulic forces may not return theswashplate to the neutral position under all conditions of operation.
The DDC is available on variable pumps and tandem pumps.
External control handle requirements
Maximum allowable trunnion torque is 79.1 N•m [700 in•lbf] for M35, and M44. Minimum torquenecessary to hold the swashplate at a zero angle for neutral is 2.3 N•m [20 in•lbf]. Maximum trunnion
angle is 16° for M35 and M44.
DDC on Left Side of M35 Pump

Trunnion

106 258

Pump Displacement vs Swashplate Rotation

t
en

Pu

la
c

em

m

p

100%

di
sp

CW
Trunnion rotation

di

sp

la
c

Pu
m
p
em
en
t

CCW
Trunnion rotation

100%

T101 306E

DDC input specs© Danfoss | July 2024

Max torque Nm [in·lbf]

79.1

[700]

Min torque Nm [in·lbf]

2.3

[20]

Max angle

M35/44: 16°

BC152886483301en-000801 | 29

Technical Information
Series 40 Direct Displacement Pumps
Options
Pump flow direction

30 | © Danfoss | July 2024

Input shaft rotation

CW

CCW

Trunnion location

Right

Trunnion rotation

CW

CCW

CW

CCW

CW

CCW

CW

CCW

Out

In

In

Out

In

Out

Out

In

Left

Right

Left

PV or front PV

Port A Flow
Fort B Flow

In

Out

Out

In

Out

In

In

Out

Rear PT

Port C (A) Fow

In

Out

Out

In

Out

In

In

Out

Port D (B) Flow

Out

In

In

Out

In

Out

Out

In

BC152886483301en-000801

Technical Information
Series 40 Direct Displacement Pumps
Installation Drawings
M35/44 Variable Pump
Auxiliary mounting flange

80.4[3.17](2) places

90.2[3.55]RUNNING COVER
106.38[4.188]53.19[2.094]

7.4 min.
[0.29]

0.375-16 Thd . thr u(4) holes

1.96[0.077]
P pitch di a.
30° pressure angl e
N teeth, 16/32 pitc hfillet root side fit
per ANSI B92.1-1970
class 5(see table)

0.5 max. R[0.02]
88.65 dia. 82.6 dia.
[3.490][3.252] 1.0 max. R[0.04]

106.38[4.188]53.19[2.094]O-Ring seal required
ref. 82.22 [3.237] IDx
2.62 [0.103] dia. cross section
Y min.

System po rts(ref.)M min.

SAE A Auxiliary mounting flange
Options A and D

Mounting flange(ref.)

Option A:248.7 [10.15]
Option D:264.0 [10.39]

Mounting flange(ref.)
261.2 [10.66]

73.03[2.875]146.05[5.75]Y min.

O-Ring seal required
2.62 [0.103] dia.
cross section

107.82[4.245]

M min.

P pitch di a.
30° pressure angl e
N teeth, 16/32 pitc hfillet root side fit
per ANSI B92.1-1970
class 5(see table)

0.76 max.R
101.65 dia.
[0.30][4.002]
0.5 max.R[0.02]

0.500-13 Thd . thr u(2) holes
System po rts(ref.)

1.96 [0.077]
10.7 min. [0.42]

SAE B Auxiliary mounting flange
Option B

P100 615E

M35/44 PV Auxiliary mounting flange and coupling option© Danfoss | July 2024

Auxiliary mounting flange

Spline pitch dia.
P

No. teeth
N

Shaft clearanceY

Coupling clearance
M

SAE A

Option A

14.30 [0.563]

9

33.0 [1.30]

9.1 [0.36]

SAE A

Option D

17.46 [0.688]

11

39.1 [1.54]

9.1 [0.36]

SAE B

Option B

20.72 [0.813]

13

42.9 [1.69]

22.3 [0.91]

BC152886483301en-000801 | 31

Technical Information
Series 40 Direct Displacement Pumps
Installation Drawings
Pump, filtration/charge pump option, control
9/16 - 18*
system pressur egauge po rt M2(for po rt B)

Mounting flange(ref.)
203.4[8.01]

7/8 - 14*
to remote filter D(pressure filter option)

96.5[3.80](2) placesB

1-1/16 - 12*case outlet L1
Charge pressur erelief valve

74.9 min. dia.
[2.95]
101.6 dia.
[4.000]

7/8 - 14*charge pressur egauge po rt M3(suction filter option)
9/16 - 18*
system pressur egauge po rt M1(for po rt A)

9.4[0.37]

66.7[2.625]239.3[9.42]

76.2[3.00](2) placescase outlets

Section B-B

125[4.92]
111.8[4.40]

16° max. displ.
15.24 dia.
[0.600](2)places

CCW

14.27 dia.
[0.562](2) Places

121.4[4.78]
193.3[7.61]

95[3.74]

3.3[0.13]

CW

73.03[2.875](2) Places

4.57 R[0.180](4) places

25.4[1.00]

1-5/16 - 12*
charge pump inlet S

Pump

B

Top view
Remote filtration or less charge pump

Approx.center of gr avity
16° max. displ.

35.6[1.40]

79.8[3.14](2) places

7/8 - 14*from remote filter E(pressure filter option)or charge pressure inlet E(no charge pump option)

Top view
Suction filtration
Bypass/check/relief valve
this side for po rt A
opposite side f or po rt B
(5/16 internal hex)

183.4
[7.22]

12.7[0.50]
Control trunnion
left side
option DL

96.5[3.80]
Control side

92.5
[3.64]

87.4[3.44](2) Places

Control trunnion
right side
option DR

1-1/16 - 12*Case outlet L2(Alternate)
1-1/16 - 12*
Port A45
0.8 R max.
[0.03]

35[1.38]

M35:19.8 dia.
[0.781]
M44:23.8 dia.
[0.938]M44:
19.0 [0.748](2) places35[1.38]
1-1/16 - 12*
Port B

M35:
15.8 [0.623](2) places

M35 Control trunion detail
164.6[6.48]

P104 614E*All ports are SAE straight thread o-ring ports per SAE J514, unless otherwise specified.
Shaft rotation is determined by viewing pump from input shaft end.
Contact your Danfoss representative for specific installation drawings.
32 | © Danfoss | July 2024

BC152886483301en-000801

Technical Information
Series 40 Direct Displacement Pumps
Installation Drawings
Dimensions in mm [in]M35/44 Tandem Pump
Charge pump options, auxiliary mounting flanges
Charge pressur erelief valve

C

84.8[3.34]C

Pump
VIEW C-C

7/8 - 14*charge pressure inlet E(w/o charge pump)

Top view (withoutcharge pump)

216.9[8.54]

106.38[4.188]53.19[2.094]

7.4 min.
[0.29]
1.96[0.077]

0.5 max.R[0.02]
82.6 dia.
88.65 dia. [3.252][3.490]1.0 max.R[0.04]Y min.
Mounting flange(ref.)
Mounting flange(ref.)

O-Ring seal required
ref. 101.27 [3.987] IDx
2.62 [0.103] dia. crosssection23.1 min.
[0.91]Y min.

1.96[0.077]53.19[2.094]w/ charge pum p
option A: 455.2 [17.92]
option D: 461.3 [18.16]

10.7 min.
[0.42]

System po rts(ref.)SAE A Auxiliary mounting flange
Options A and D

w/o charge pum p
option A: 433.1 [16.55]
option D: 426.5 [16.79]
w/ charge pum p
467.9 [18.42]
w/o charge pum p433.1 [17.05]

P pitch di a.
O teeth, 16/32 pitc hfillet root side fit
per ANSI B92.1-1970
class 50.76 max.R
107.82 dia.
[0.03][4.245]101.65 dia.
[4.002]
0.5 max.R[0.02]© Danfoss | July 2024

106.38[4.188]

P pitch di a.
30° pressure angl e
N teeth, 16/32 pitc hfillet root side fit
per ANSI B92.1-1970
class 5(see table)

O-Ring seal required
ref. 82.22 [3.237] IDx
2.62 [0.103] dia. cross section
9.1 [0.36] min.

0.375-16 Thd.
17.8 [0.70] min . t h d .
(4) places0.500-13 Thd.
20.8 [0.82] min. full thd.
(2) places146.05[5.75]
73.03[2.875]

System po rts(ref.)SAE B Auxiliary mounting flange
Option B

P100 617E

BC152886483301en-000801 | 33

Technical Information
Series 40 Direct Displacement Pumps
Installation Drawings
M35/44 PT Auxiliary mounting flange and coupling options

34 | © Danfoss | July 2024

Auxiliary mounting
flangeSpline pitch dia.
P

No. teeth
N

Shaft clearanceY

Coupling clearance
M

SAE A

Option A

14.30[.563]

933.0[1.30]

9.1[0.36]SAE A

Option D

17.46[.688]

11

39.1[1.54]

9.1
[.36]

SAE B

Option B

20.72[0.813]13

42.9[1.69]

22.3[0.91]BC152886483301en-000801

Technical Information
Series 40 Direct Displacement Pumps
Installation Drawings
Pumps, filtration/charge pump options, control
315.5 [12.42]
w/ chg. pum p

9/16 - 18*
system pressur egauge po rt M4(for po rt D)

280.7 [11.05]
w/o chg. pum p

Mounting flange(ref.)

charge pressur erelief valve

7/8 - 14*Charge pressur egauge po rt E

203.4
[8.01]

7/8 - 14*
to remote filter D

9.4[0.37]

183.4[7.22]

B

1-1/16 - 12*case outlet(alternate) L2

74.9 min. dia.
[2.95]
101.6 dia.
[4.00]

9/16 - 18*
system pressur egauge po rt M1(for po rt A)
system pressur egauge po rt M2(for po rt B)(on right side)

79.8[3.14](2) places

35.6[1.40]Pump

B

VIEW "B-B"

7/8 - 14*from remote filter E

Top view(with charge pump andsuction filtration)

Bypass/check/relief valve
this side for po rt C and A
opp .s ide for Port D and B(5/16 internal hex)

345.3 [13.59]
w/chg. pum p

16° max.
displ.

16° max.
displ.

Top view(with charge pump andremote pressure filtration)

66.7[2.625]310.3 [12.215]
w/o chg. pum p
16° Max.
displ.

16° Max.
displ.
15.24 dia.
[0.600](4) places

25.4[1.00]

125[4.92]
111.8[4.40]

CCW

14.27 [0.562](2) places95[3.74]

CW"X"
80.3 [3.16](4) places
76.2[3.00](2) placescase outlets

9/16 - 18*
system pressur eguage po rt M3(for po rt C)

1-5/16 - 12*
charge pump inlet S

193.3[7.61]

12.7 [0.50]

Left side view
(with charge pump and suction filtration)

1-1/16 - 12*case outlet L1

428.8 [16.88]
w/ chg. pum p393.7 [15.50]
w/o chg. pum p

73.03 [2.875](2) places
87.4 [3.44](2) places

4.57 R[0.180](8) places247.1 [9.73]
w/ chg. pum pControl trunnion
left side
option DL

212.3 [8.36]
w/o chg. pum p
164.6[6.48]
0.8 R max.
[0.03]

88.9[3.50]

96.5[3.80]
Control side

M35:19.8 dia.
[0.78]
M44:23.8 dia.
[0.938]35[1.38]

Control trunnion
right side
option DR

92.5[3.64]

45°

M35:
15.8 [0.623](2) places
M44:
19.0 [0.748](2) places35[1.38]

M35 Control trunion detail1-1/16 - 12*
Port A1-1/16 - 12*
Port C
1-1/16 - 12*
Port D
Approx Center Of Gravity

1-1/16 - 12*
Port B
205.7 [8.10]
188.7 [7.43]
w/ chg. pum p
w/o chg. pum p

Bottom view
(with charge pump and suction filtration)

P100 616E*All ports are SAE straight thread o-ring ports per SAE J514, unless otherwise specified.
Shaft rotation is determined by viewing pump from input shaft end.
© Danfoss | July 2024

BC152886483301en-000801 | 35

Technical Information
Series 40 Direct Displacement Pumps
Installation Drawings
Contact your Danfoss representative for specific installation drawings.
Dimensions in mm [in]36 | © Danfoss | July 2024

BC152886483301en-000801

Technical Information
Series 40 Direct Displacement Pumps
Performance Data
Performance
The following performance graph provides typical volumetric and overall efficiencies for Series 40
pumps. These efficiencies apply for all Series 40 pumps.
Pump performance as a function of operating speed
100
ficiency
Vo lu m et ric ef

Efficiency - %

95

90

85

80

e ra
Ov

0

- 170 bar [2500 psi]e t ric efficien cy - 345 bar [5000 psi]
Vo lu mOve rall ef
ficien cy- 170 b ar
[2500 p si
]
ba
r
[5000
5
4
3
psi]
y
c
en
i
c
fi
f
ll e

25

50

75

Speed - % of rated speed

100
T101 304E

The performance map provides typical pump overall efficiencies at various operating parameters. These
efficiencies also apply for all Series 40 pumps.

System pressur e

psi
5000

270

4000

210

3000

140

2000

70

1000

0

0

85

bar
345

80%

Pump performance as a function of operating speed and system pressure
%

87%

88%

8 8%

0

87%

85%

25
50
75
Speed - % of ra ted speed

80%

100
T101 305E© Danfoss | July 2024

BC152886483301en-000801 | 37

Technical Information
Series 40 Direct Displacement Pumps
Schematics
Single Pump Schematics
M35/44 PV
Remote pressure filtration(no charge pump)
Remote Pressure Filtration
E

E

D
Suction Filtration
E M3
L2
A
M1

M2
B
L1

No relief valve

S
P100 638E

Tandem Pump Schematics
M35/44 PT
Remote pressur e
filtration(no charge pump)

Remote pressur e
filtration

E

E

D
Suction filtration
E

L2
C

A

M3

M1

M4

M2

D

B
L1

38 | © Danfoss | July 2024

S

No ReliefValve
P100 641E

BC152886483301en-000801

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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
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© Danfoss | July 2024

BC152886483301en-000801