Danfoss Series 90 Axial Piston Pumps User guide

Technical Information

Series 90

Axial Piston Pumps

www.danfoss.com

Technical Information

Series 90 Axial Piston Pumps

Revision history	Table of revisions
	Date	Changed	Rev
	March 2022	Additional note onto Mating pump requirements at Features and Options	0910
	September 2021	Modified KN at control option "M" on MMC	0909
	June 2021	Deleted Size 042 information.	0908
	March 2020	Removed restricted options	0907
	February 2020	Changed document number from BC00000015 and increased version by 0101	0906
	January 2020	Corrected 075 dimension drawing	0805
	March 2016	Minor edit	0804
	January 2015	correction to O-ring sizing - page 77	HC
	May 2014	corrections to pin assignments - page 48	HB
	February 2014	Danfoss Layout	HA

2 | © Danfoss | March 2022

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Technical Information
Series 90 Axial Piston Pumps
Contents
General Description
Series 90 Family of Pumps and Motors.....................................................................................................................................	5
PLUS+1 Compliant Controls and Sensors................................................................................................................................	5
Design...................................................................................................................................................................................................	6
Series 90 Pictorial Circuit Diagram.............................................................................................................................................	7
System schematic.............................................................................................................................................................................	7
Technical Specifications
General Specifications....................................................................................................................................................................	8
Features and Options......................................................................................................................................................................	8
Operating Parameters.....................................................................................................................................................................	9
Fluid Specification............................................................................................................................................................................	9
Operating Parameters
Input Speed......................................................................................................................................................................................	10
Independent Braking System...............................................................................................................................................	10
System Pressure..............................................................................................................................................................................	10
Servo Pressure.................................................................................................................................................................................	12
Charge Pressure..............................................................................................................................................................................	12
Charge Pump Inlet Pressure.......................................................................................................................................................	12
Case Pressure...................................................................................................................................................................................	12
External Shaft Seal Pressure.......................................................................................................................................................	13
Temperature....................................................................................................................................................................................	13
Viscosity.............................................................................................................................................................................................	13
System Design Parameters
Filtration System.............................................................................................................................................................................	14
Filtration Options...........................................................................................................................................................................	14
Suction filtration – Option S.................................................................................................................................................	14
Charge pressure filtration (partial charge pump flow)...............................................................................................	15
Remote charge pressure filtration......................................................................................................................................	15
Fluid Selection.................................................................................................................................................................................	15
Reservoir............................................................................................................................................................................................	15
Case Drain.........................................................................................................................................................................................	16
Pump Life..........................................................................................................................................................................................	16
Charge Pump...................................................................................................................................................................................	16
Charge pump sizing/selection.............................................................................................................................................	16
Bearing Loads and Life.................................................................................................................................................................	17
Applications with external shaft loads..............................................................................................................................	17
Understanding and Minimizing System Noise....................................................................................................................	18
Sizing Equations.............................................................................................................................................................................	18
Mounting Flange Loads...............................................................................................................................................................	19
Master Model Code
Series 90 Master Model Code Breakdown............................................................................................................................	21
S90 Rotation and Size Options..................................................................................................................................................	21
Control Options..............................................................................................................................................................................	22
Pressure, Aux Mounting, Ports, Filtration, Displacement Limitation Options.........................................................	23
Shaft and Charging System........................................................................................................................................................	24
Control Orifice Options................................................................................................................................................................	25
Special Hardware and Pressure Settings...............................................................................................................................	26
Control Features
3-Position (FNR) Electric Control - DC, DD............................................................................................................................	27
Response time...........................................................................................................................................................................	28
Electric Displacement Control (EDC), Options KA, KP, KT................................................................................................	28
Features and Benefits..............................................................................................................................................................	28
Response time...........................................................................................................................................................................	31
Pump output flow direction vs. control current............................................................................................................	31
Manual Over Ride (MOR).............................................................................................................................................................	32
Hydraulic Displacement Control (HDC), Option HF, HS...................................................................................................	33

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Technical Information
Series 90 Axial Piston Pumps
Contents
Operation.....................................................................................................................................................................................	33
Features and Benefits..............................................................................................................................................................	33
Response time...........................................................................................................................................................................	34
Pump output flow direction vs. control pressure.........................................................................................................	34
Manual Displacement Control (MDC), Options MA, MB..................................................................................................	35
Features and benefits..............................................................................................................................................................	35
External control handle requirements..............................................................................................................................	36
Response Time...........................................................................................................................................................................	36
Pump output flow direction vs. control handle rotation...........................................................................................	37
Neutral start switch (NSS) for MDC..........................................................................................................................................	37
Non Feedback Proportional Electric Control (NFPE) ........................................................................................................	37
Control response.......................................................................................................................................................................	37
NFPE control used with a Danfoss microcontroller......................................................................................................	38
Input signal requirements.....................................................................................................................................................	38
Features and Options
Multi-Function Valves...................................................................................................................................................................	40
Overpressure protection........................................................................................................................................................	40
Pressure limiting function.....................................................................................................................................................	40
Bypass Function........................................................................................................................................................................	41
Auxiliary Mounting Pads.............................................................................................................................................................	41
Mating pump requirements.................................................................................................................................................	41
Displacement Limiter...................................................................................................................................................................	42
Shaft Torque.....................................................................................................................................................................................	43
Shaft torque and spline lubrication...................................................................................................................................	43
Shaft torque for tapered shafts............................................................................................................................................	43
Shaft Availability and Torque Ratings.....................................................................................................................................	44
Tapered Shaft Customer Acknowledgement.................................................................................................................	45
Charge Pump...................................................................................................................................................................................	45
Charge pump sizing/selection.............................................................................................................................................	45
Charge pump flow and power curves...............................................................................................................................	46
Speed Sensor...................................................................................................................................................................................	47
Connector Pin Assignments.......................................................................................................................................................	49
Installation Drawings
Frame Size 055................................................................................................................................................................................	50
Frame Size 075................................................................................................................................................................................	54
Frame Size 075 NFPE Options FK, FL, FM, FN.......................................................................................................................	57
Frame Size 100................................................................................................................................................................................	62
Frame Size 130................................................................................................................................................................................	67
Frame Size 180................................................................................................................................................................................	71
Frame Size 250................................................................................................................................................................................	75
Cover Plate........................................................................................................................................................................................	78
3-Position (F-N-R) Electric Control...........................................................................................................................................	79
Electric Displacement Control (EDC) with MS-Connector or Packard® connector.................................................	80
Hydraulic Displacement Control (HDC).................................................................................................................................	80
Manual Displacement Control (MDC) with neutral start switch...................................................................................	81
Electrohydraulic Displacement Control (NFPE)(except 075 NFPE)..............................................................................	82
Integral Pressure Filter.................................................................................................................................................................	83
Remote pressure – without filter..............................................................................................................................................	83

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Technical Information

Series 90 Axial Piston Pumps

General Description

Series 90 Family of Pumps and Motors

Series 90 hydrostatic pumps and motors can be applied together or combined with other products in a system to transfer and control hydraulic power. They are intended for closed circuit applications.

•Series 90 – advanced technology

•Seven sizes of variable displacement pumps

•Proven reliability and performance

•Compact, lightweight

•Worldwide sales and service

•PLUS+1™ compliant controls and sensors

Series 90 variable displacement pumps are compact, high power density units. All models utilize the parallel axial piston/slipper concept in conjunction with a tiltable swashplate to vary the pump’s displacement. Reversing the angle of the swashplate reverses the flow of oil from the pump and thus reverses the direction of rotation of the motor output.

Series 90 pumps include an integral charge pump to provide system replenishing and cooling oil flow, as well as control fluid flow. They also feature a range of auxiliary mounting pads to accept auxiliary hydraulic pumps for use in complementary hydraulic systems. A complete family of control options is available to suit a variety of control systems (mechanical, hydraulic, electric).

Series 90 motors also use the parallel axial piston/slipper design in conjunction with a fixed or tiltable swashplate. They can intake/discharge fluid through either port; they are bidirectional. They also include an optional loop flushing feature that provides additional cooling and cleaning of fluid in the working loop. For more information on Series 90 motors, refer to Series 90 Motors Technical Information

BC152886483265.

PLUS+1 Compliant Controls and Sensors

A wide range of Series 90 controls and sensors are PLUS+1™ compliant. PLUS+1 compliance means our controls and sensors are directly compatible with the PLUS+1 machine control architecture. Adding Series 90 pumps to your application using PLUS+1 GUIDE software is as easy as drag-and-drop. Software development that used to take months can now be done in just a few hours. For more information on PLUS+1 GUIDE, visit www.sauer-danfoss.com/plus1.

Series 90 pumps can be used together in combination with other Danfoss pumps and motors in the overall hydraulic system. Danfoss hydrostatic products are designed with many different displacement, pressure and load-life capabilities.

Go to the Danfoss website or applicable product catalog to choose the components that are right for your complete closed circuit hydraulic system.

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Technical Information

Series 90 Axial Piston Pumps

General Description

Design

Series 90 pump cross-section

	Piston
	Slipper
Slider block	Displacement control
	Servo arm
	Servo piston

			Feedback linkage
			Cradle bearing
Bushing
Cylinder block			Roller bearing
			Shaft
Valve plate			seal
Rear
bushing
			Input shaft
Charge pump	Swashplate	Cradle guide	P106 648E

Typical name plate

			Model-No./Ident-No.			501829	Model
			Model Code 90L055	KA	1	N	Number
Model			6 S 3 C6 C 03
			NNN	35	35	24
Code
			Serial-No.	A - 88 - 126 - 67890			Serial

Number

Made in USA

P108494E

Place of Manufacture

Series 90 pumps are also manufactured in Europe and China. Place of manufacture shown on nameplate will correspond with the actual place of manufacture.

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Technical Information

Series 90 Axial Piston Pumps

General Description

Series 90 Pictorial Circuit Diagram

The circuit diagram shows a hydrostatic transmission using a Series 90 axial piston variable displacement pump and a Series 90 fixed displacement motor.

Control handle	Displacement control valve
		Heat exchanger bypass valve
		Orificed heck	Reservoi
				Vacuum gauge
		valve
					valve	P102 000
Reversiblevariable	Servo control cylinder				Fixed displacement motor
displacement pump
			To
			pump
		Servo	case
		pressure
		relief valves
		Charge pump
Input shaft		Multi-function valve				Output shaft
				Motor swashplate
Pump swashplate	Servo control cylinder			Loop flushing valve
		Pump			Motor
Working loop (high pressure)		Working loop (low pressur e)	Suction line	Control fluid	Case drain fluid

System schematic
	M3		L2	M3	M1
		A	A
M1
M4
M5
M
M2
		B	B
S		L2	L1		M2	P104 286E
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Technical Information

Series 90 Axial Piston Pumps

Technical Specifications

General Specifications

Design	Axial piston pump of cradle swashplate design with variable displacement
Direction of rotation	Clockwise, counterclockwise
Pipe connections	Main pressure ports: ISO split flange boss
	Remaining ports: SAE straight thread O-ring boss
Recommended installation position	Pump installation position is discretionary, however the recommended control position is on the top
	or at the side, with the top position preferred.
	Vertical input shaft installation is acceptable.
	If input shaft is at the top 1 bar case pressure must be maintained during operation.
	The pump housing must be filled with hydraulic fluid under all conditions; including after a long
	period of shutdown. Before operating the machine, ensure the pump housing and case drain lines are
	free of air.
	Recommended mounting for a multiple pump stack is to arrange the highest power flow towards the
	input source.
	Consult Danfoss for nonconformance to these guidelines.
Auxiliary cavity pressure	Will be inlet pressure with internal charge pump. For reference see Operating Parameters. Will be case
	pressure with external charge supply.
	Please verify mating pump shaft seal capability.

Features and Options

Feature	Unit	Frame
		055		075		100	130	180		250
Displacement	cm³/rev.	55		75		100	130	180		250
	[in³]/rev.	[3.35]		[4.59]		[6.10]	[7.93]	[10.98]		[15.25]
Flow at rated speed (theoretical)	l/min.	215		270		330	403	468		575
	[US gal/min.]	[57]		[71]		[87]	[106]	[124]		[160]
Torque at maximum displacement	N•m/bar	0.88		1.19		1.59	2.07	2.87		3.97
(theoretical)	[lbf•in/1000	[530]		[730]		[970]	[1260]	[1750]		[2433]
	psi]
Mass moment of inertia of rotating	kg•m²	0.0060		0.0096		0.0150	0.023	0.0380		0.0650
components	[slug•ft²]	[0.0044]		[0.0071]		[0.0111]	[0.0170]	[0.0280]		[0.0479]
Weight (with control opt. MA)	kg [lb]	40 [88]		49 [108]		68 [150]	88 [195]	136 [300]		154 [340]
Mounting (per ISO 3019-1)		Flange					Flange	Flange
		127-4 (SAE C)					152-4 (SAE D)	165-4 (SAE E)
Rotation		Right hand or Left hand rotation
Main ports: 4-bolt split-flange	mm	25.4		25.4		25.4	31.75	31.75		38.1
(per SAE J518 code 62)	[in]	[1.0]		[1.0]		[1.0]	[1.25]	[1.25]		[1.5]
Main port configuration		Twin or side port					Twin port
Case drain ports (SAE O-ring boss)	UNF thread	1.0625–12		1.0625–12		1.0625–12	1.3125–12	1.625–12		1.625–12
	(in.)
Other ports		SAE O-ring boss
Shafts		Splined, and tapered shafts available
Auxiliary mounting		SAE-A, B, C					SAE-A, B, C, D	SAE-A, B, C, D, E

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Technical Information

Series 90 Axial Piston Pumps

Technical Specifications

Operating Parameters

Parameter	Unit	Frame
		055	075	100	130	180	250
Input speed
Minimum	min-1(rpm)	500	500	500	500	500	500
Rated Speed		3900	3600	3300	3100	2600	2300
Maximum		4250	3950	3650	3400	2850	2500

Operating parameters

System pressure	Maximum working pressure	bar	[psi]	450	[6525]
	Maximum pressure			480	[6960]
	Maximum low loop			45	[650]
	Minimum low loop pressure			10	[145]
Charge pressure	Minimum	bar	[psi]	18	[261]
	Maximum			34	[493]
Control pressure	Minimum (at corner power for EDC and FNR)	bar	[psi]	14	[203]
	Minimum (at corner power for NFPE)			22	[319]
	Maximum			40	[580]
Charge pump inlet	Rated	bar (absolute)	[in Hg vacuum]	0.7	[9]
pressure
	Minimum (cold start)			0.2	[24]
	Maximum	bar	[psi]	4.0	[58]
Case pressure	Rated	bar	[psi]	3.0	[44]
	Maximum			5.0	[73]
Lip seal external pressure	Maximum	bar	[psi]	0.4	[5.8}

Fluid Specification

Viscosity

Intermittent1)	5 mm2/s [42 SUS]
Minimum	7 mm2/s [49 SUS]
Recommended range	12 – 80 mm2/s [66 – 370 SUS]
Maximum	1600 mm2/s [7500 SUS]

1) Intermittent = Short term t < 1 min per incident and not exceeding 2 % of duty cycle based load-life.

Temperature

Minimum 1)	-40°C [-40°F]
Rated	104°C [220°F]
Recommended range2)	60 – 85°C [140 – 185°F]
Maximum Intermittent	115°C [240°F]

1)Cold start = Short term t > 3 min, p ≤ 50 bar [725 psi], n ≤ 1000 min-1 (rpm).

2)At the hottest point, normally case drain port.

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Technical Information

Series 90 Axial Piston Pumps

Operating Parameters

Input Speed

Minimum	is the lowest input speed recommended during engine idle condition. Operating below
speed	minimum speed limits the pump’s ability to maintain adequate flow for lubrication and
	power transmission.
Rated speed	is the highest input speed recommended at full power condition. Operating at or
	below this speed should yield satisfactory product life.
	Operating conditions between rated and maximum speed should be restricted to less
	than full power and to limited periods of time.
Maximum	is the highest operating speed permitted. Exceeding maximum speed reduces product
speed	life and can cause loss of hydrostatic power and braking capacity. For most drive
	systems, maximum unit speed occurs during downhill braking or negative power
	conditions.
	W Warning
	Never exceed the maximum speed limit under any operating conditions.

During hydraulic braking and downhill conditions, the prime mover must be capable of providing sufficient braking torque in order to avoid pump over speed. This is especially important to consider for turbo-charged and Tier 4 engines.

For more information please see Pressure and Speed Limits, BC152886484313, when determining speed limits for a particular application.

Independent Braking System

Unintended vehicle or machine movement hazard. Exceeding maximum speed may cause a loss of hydrostatic drive line power and braking capacity.

Machine manufacturer is responsible to provide a braking system, redundant to the hydrostatic transmission, sufficient to stop and hold the vehicle or machine in the event of hydrostatic drive power loss. The braking system must also be sufficient to hold the machine in place when full power is applied.

System Pressure

Hydraulic unit life depends on the speed and normal operating — or weighted average — pressure that can only be determined from a duty cycle analysis.

System pressure is the differential pressure between high pressure system ports. It is the dominant

	operating variable affecting hydraulic unit life. High system pressure, which results
	from high load, reduces expected life.
Application	is the high pressure relief or pressure limiter setting normally defined within the
pressure	order code of the pump. This is the applied system pressure at which the drive line
	generates the maximum calculated pull or torque in the application.
Maximum	is the highest recommended application pressure and is not intended to be a
working	continuous pressure. Propel systems with application pressures at, or below this
pressure	pressure should yield satisfactory unit life given proper component sizing.
	Application pressures above maximum working pressure will only be considered
	with duty cycle analysis and factory approval.
	Pressure spikes are normal and must be considered when reviewing maximum
	working pressure.

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Technical Information

Series 90 Axial Piston Pumps

Operating Parameters

	Maximum	is the highest intermittent pressure allowed under any circumstances. Applications
	pressure	with applied pressures between rated and maximum require factory approval with
		complete application, duty cycle, and life expectancy analysis.
	Minimum low	must be maintained under all operating conditions to avoid cavitation.
	loop pressure
		All pressure limits are differential pressures referenced to low loop (charge) pressure.
		Subtract low loop pressure from gauge readings to compute the differential.

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Technical Information

Series 90 Axial Piston Pumps

Operating Parameters

Servo Pressure

Servo pressure is the pressure in the servo system needed to position and hold the pump on stroke. It depends on system pressure and speed. At minimum servo pressure the pump will run at reduced stroke depending on speed and pressure.

Minimum servo pressure at corner power holds the pump on full stroke at max speed and max pressure.

Maximum servo pressure is the highest pressure typically given by the charge pressure setting.

Charge Pressure

An internal charge relief valve regulates charge pressure. Charge pressure supplies the control with pressure to operate the swashplate and to maintain a minimum pressure in the low side of the transmission loop.

The charge pressure setting listed in the order code is the set pressure of the charge relief valve with the pump in neutral, operating at 1800 min-1 (rpm), and with a fluid viscosity of 32 mm2/s [150 SUS].

Pumps configured with no charge pump (external charge supply) are set with a charge flow of 30 l/min [7.93 US gal/min] and a fluid viscosity of 32 mm2/s [150 SUS].

The charge pressure setting is referenced to case pressure. Charge pressure is the differential pressure above case pressure.

Minimum	is the lowest pressure allowed to maintain a safe working condition in the low side of
charge	the loop. Minimum control pressure requirements are a function of speed, pressure,
pressure	and swashplate angle, and may be higher than the minimum charge pressure shown
	in the Operating parameters tables.
Maximum	is the highest charge pressure allowed by the charge relief adjustment, and which
charge	provides normal component life. Elevated charge pressure can be used as a
pressure	secondary means to reduce the swashplate response time.

Charge Pump Inlet Pressure

At normal operating temperature charge inlet pressure must not fall below rated charge inlet pressure (vacuum).

Minimum charge inlet	is only allowed at cold start conditions. In some applications it is
pressure	recommended to warm up the fluid (e.g. in the tank) before starting the
	engine and then run the engine at limited speed.
Maximum charge inlet	may be applied continuously.
pressure

Case Pressure

Under normal operating conditions, the rated case pressure must not be exceeded. During cold start case pressure must be kept below maximum intermittent case pressure. Size drain plumbing accordingly.

The auxiliary pad cavity of axial pumps configured without integral charge pumps is referenced to case pressure. Units with integral charge pumps have auxiliary mounting pad cavities referenced to charge inlet (vacuum).

Possible component damage or leakage.

Operation with case pressure in excess of stated limits may damage seals, gaskets, and/or housings, causing external leakage. Performance may also be affected since charge and system pressure are additive to case pressure.

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Series 90 Axial Piston Pumps

Operating Parameters

External Shaft Seal Pressure

In certain applications the input shaft seal may be exposed to external pressure. In order to prevent damage to the shaft seal the maximum differential pressure from external sources must not exceed 0.4 bar (5.8 psi) over pump case pressure.

The case pressure limits of the pump must also be followed to ensure the shaft seal is not damaged.

C Caution

Regardless of the differential pressure across the shaft seal, the shaft seal has been known to pump oil from the external source (e. g. gear box) into the pump case.

Temperature

The high temperature limits apply at the hottest point in the transmission, which is normally the motor case drain. The system should generally be run at or below the quoted rated temperature.

The maximum intermittent temperature is based on material properties and should never be exceeded.

Cold oil will generally not affect the durability of the transmission components, but it may affect the ability of oil to flow and transmit power; therefore temperatures should remain 16 °C [30 °F] above the pour point of the hydraulic fluid.

The minimum temperature relates to the physical properties of component materials.

Size heat exchangers to keep the fluid within these limits. Danfoss recommends testing to verify that these temperature limits are not exceeded.

Viscosity

For maximum efficiency and bearing life, ensure the fluid viscosity remains in the recommended range.

The minimum viscosity should be encountered only during brief occasions of maximum ambient temperature and severe duty cycle operation.

The maximum viscosity should be encountered only at cold start.

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Technical Information

Series 90 Axial Piston Pumps

System Design Parameters

Filtration System

To prevent premature wear, ensure only clean fluid enters the hydrostatic transmission circuit. A filter capable of controlling the fluid cleanliness to ISO 4406 class 22/18/13

(SAE J1165) or better, under normal operating conditions, is recommended.

These cleanliness levels can not be applied for hydraulic fluid residing in the component housing/case or any other cavity after transport.

The filter may be located on the pump (integral) or in another location (remote).

The integral filter has a filter bypass sensor to signal the machine operator when the filter requires changing. Filtration strategies include suction or pressure filtration. The selection of a filter depends on a number of factors including the contaminant ingression rate, the generation of contaminants in the system, the required fluid cleanliness, and the desired maintenance interval. Filters are selected to meet the above requirements using rating parameters of efficiency and capacity.

Filter efficiency can be measured with a Beta ratio¹ (βX). For simple suction-filtered closed circuit transmissions and open circuit transmissions with return line filtration, a filter

with a β-ratio within the range 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 considerably higher filter efficiency is recommended. This also applies to systems with gears or clutches using a common reservoir.

For these systems, 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 the filtration system. Please see Design Guidelines for Hydraulic Fluid Cleanliness Technical Information,

BC152886482150 for more information.

1 Filter βx-ratio is a measure of filter efficiency defined by ISO 4572. It is defined as the ratio of the number of particles greater than a given diameter (“x” in microns) upstream of the filter to the number of these particles downstream of the filter.

W Warning

Clogged filters can cause cavitation, which damages the charge pump. We recommend a filter bypass with a filter bypass sensor to prevent damage due to blocked suction filters.

Filtration Options

Suction filtration – Option S

The suction filter is placed in the circuit between the reservoir and the inlet to the charge pump, as shown below.

The use of a filter contamination monitor is recommended.

Suction filtration

Hydraulic fluidreservoir	Manomete r

Charge pump

Filter

	Adjustable
To low	charge pressure relief valve
loop and	To pump case	P102 003E
control

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Series 90 Axial Piston Pumps

System Design Parameters

Charge pressure filtration (partial charge pump flow)

Two types of pressure filtration exist for most Series 90 pumps. The two types are: remote pressure filtration (filter remotely mounted on vehicle) and integral pressure filtration (filter mounted to the endcap). Verify option availability in the size specific technical information.

In either case the filtration circuit is the same with the filter element situated in the circuit downstream the charge pump and upstream of the charge relief valve such that full charge flow is continuously filtered, as shown in the accompanying illustrations. Charge pressure filtration can mitigate high inlet vacuum in cold start-ups and provides fluid filtration immediately prior to entrance to the loop and the control system. Pressure filtration provides a higher level of filtering efficiency than suction filtration.

Filters used in charge pressure filtration circuits must be rated to at least 35 bar [508 psi] pressure. A 100 – 125 μm screen located in the reservoir or in the charge inlet line is recommended when using charge pressure filtration.

Technical data according to ISO 16889

Nominal flow at 30mm2/s and ∆P 0.5 bar[7.3 psi] (clean filter element only)		Minimum β-ratio
Short	60 l/min	β7.5(C)=75 (β5(C) ≥10)
Long	105 l/min

Remote charge pressure filtration

A special adapter head is available to allow for the charge filter to be located conveniently for easy service and replacement. Care should be taken to minimize the hydraulic pressure drops associated with long connecting lines, small diameter hoses, or restrictive port adaptors at the filter head or endcap. Ensure the normal operating pressure drop across the remote filtration in and out ports is sufficiently below the crack pressure setting of the recommended filter bypass valve.

Charge pressure filtration

	Screen
Hydraulic fluid reservoi		Adjustable
		charge pressure
		relief valve
	Charge pump
To low	Filter	To pump case
pressure
side and		P102 004E
control

W Warning

Remote filter heads without bypass and poor plumbing design can encounter excessive pressure drops that can lead to charge pump damage in addition to contaminants being forced through the filter media and into the transmission loop.

Fluid Selection

Ratings and performance data are based on operating with hydraulic fluids containing oxidation, rust and foam inhibitors. These fluids must possess good thermal and hydrolytic stability to prevent wear, erosion, and corrosion of pump components.

Never mix hydraulic fluids of different types.

Reservoir

The hydrostatic system reservoir should accommodate maximum volume changes during all system operating modes and promote de-aeration of the fluid as it passes through the tank. A suggested

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Technical Information

Series 90 Axial Piston Pumps

System Design Parameters

minimum total reservoir volume is 5⁄8 of the maximum charge pump flow per minute with a minimum fluid volume equal to ½ of the maximum charge pump flow per minute. This allows 30 seconds fluid dwell for removing entrained air at the maximum return flow. This is usually adequate to allow for a closed reservoir (no breather) in most applications.

Locate the reservoir outlet (charge 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. A 100-125 μm screen over the outlet port is recommended. Position the reservoir inlet (fluid return) to discharge below the normal fluid level, toward the interior of the tank. A baffle (or baffles) will further promote de-aeration and reduce surging of the fluid.

Case Drain

All single S90 pumps are equipped with multiple drain ports. Port selection and case drain routing must enable the pump housing to maintain a volume of oil not less than half full and normal operating case pressure limits of the unit are maintained. Case drain routing and design must consider unit case pressure ratings.

A case drain line must be connected to one of the case outlets to return internal leakage to the system reservoir.

Do not over torque the fitting on case drain port L2 (located on the side cover). The proper torque is 100 N•m [74 lbf•ft] maximum. Over torquing the fitting may change the neutral position of the swashplate.

Pump Life

Pump life depends on several factors, such as speed, pressure, and swashplate angle. For detailed product life calculation, please contact your Danfoss representative.

Charge Pump

Charge flow is required on all Series 90 pumps applied in closed circuit installations. The charge pump provides flow to make up internal leakage, maintain a positive pressure in the main circuit, provide flow for cooling and filtration, replace any leakage losses from external valving or auxiliary systems, and to provide flow and pressure for the control system.

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 of heat exchanger, length and size of hydraulic lines, control response characteristics, auxiliary flow requirements, hydrostatic motor type, etc. When initially sizing and selecting hydrostatic units for an application, it is frequently not possible to have all the information necessary to accurately evaluate all aspects of charge pump size selection.

Unusual application conditions may require a more detailed review of charge pump sizing. Charge pressure must be maintained at a specified level under all operating conditions to prevent damage to the transmission. Danfoss recommends testing under actual operating conditions to verify this.

Charge pump sizing/selection

In most applications a general guideline is that the charge pump displacement should be at least 10 % of the total displacement of all components in the system. Unusual application conditions may require a more detailed review of charge flow requirements. Refer to Selection of Drive line Components, BC157786484430, for a detailed procedure.

System features and conditions which may invalidate the 10 % guideline include (but are not limited to):

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Technical Information

Series 90 Axial Piston Pumps

System Design Parameters

•Continuous operation at low input speeds (< 1500 min-1 (rpm))

•High shock loading and/or long loop lines

•High flushing flow requirements

•Multiple Low Speed High Torque motors

•High input shaft speeds

Bearing Loads and Life

In vehicle propel drives with no external shaft loads , and where the system pressure and swashplate angle are changing direction and magnitude regularly, the normal L20 bearing life (80% survival) will exceed the hydraulic life of the unit.

In non-propel drives, such as vibratory drives, conveyor drives and fan drives, the operating speed and pressure are often nearly constant and the swashplate angle is predominantly at maximum. These drives have a distinct duty cycle compared to a propulsion drive. In these types of applications, a bearing life review is recommended.

For bearing life, speed, pressure, swashplate angle, plus external loads will be considered. Other factors that affect bearing life include fluid type, viscosity, and cleanliness.

Applications with external shaft loads

External loads are found in applications where the pump is driven with a side/thrust load (belt drive or gear drive) as well as in installations with misalignment and improper concentricity between the pump and drive coupling. All external loads act to reduce bearing life.

In applications where you cannot avoid external radial shaft loads, orient the load to 0° or 180° position. Use tapered output shafts or clamp-type couplings where radial shaft loads are present.

In addition, external thrust loads can reduce bearing life in systems with low delta pressure or in combination with external radial loads/bending moments.

Re = Me / L

Me = Shaft moment L = Flange distance Re = External force

Radial load position

B

A

	0°Re
L
Re
270°	90°
Re	Re

180°Re

P108 549E

Maximum allowable external shaft load

Parameter	055	075	100	130	180	250
External moment (Me)	101	118	126	140	*	*
N•m [lbf•in]	[893]	[1043]	[1114]	[1238]

* no tapered shaft available

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Technical Information

Series 90 Axial Piston Pumps

System Design Parameters

If continuous applied external radial loads are 25% of the maximum allowable or more or thrust loads/ bending moments known to occur, contact your Danfoss representative for an evolution of bearing life.

Avoid external thrust loads in either direction.

Understanding and Minimizing System Noise

Noise is transmitted in fluid power systems in two ways: as fluid borne noise, and structure borne noise.

Fluid-borne noise (pressure ripple or pulsation) is created as pumping elements discharge oil into the pump outlet. It is affected by the compressibility of the oil, and the pump's ability to transition pumping elements from high to low pressure. Pulsations travel through the hydraulic lines at the speed of sound (about 1400 m/s [4600 ft/sec] in oil) until there is a change (such as an elbow) in the line. Thus, amplitude varies with overall line length and position.

Structure born noise is transmitted wherever the pump casing connects to the rest of the system. The way system components respond to excitation depends on their size, form, material, and mounting.

System lines and pump mounting can amplify pump noise.

Follow these suggestions to help minimize noise in your application:

•Use flexible hoses.

•Limit system line length.

•If possible, optimize system line position to minimize noise.

•If you must use steel plumbing, clamp the lines.

•If you add additional support, use rubber mounts.

•Test for resonants in the operating range; if possible avoid them.

Sizing Equations

The following equations are helpful when sizing hydraulic pumps. Generally, the sizing process is initiated by an evaluation of the machine system to determine the required motor speed and torque to perform the necessary work function. Refer to Selection of drive line components, BC157786484430, for a more complete description of hydrostatic drive line sizing. First, the motor is sized to transmit the maximum required torque. The pump is then selected as a flow source to achieve the maximum motor speed.

SIunits

Output f ow Q =

Vg • n • ηv

(l/min..)

1000

Input torque M=

Vg • p

(N•m)

20 • π • ηm

Input power P =

M • n • π

=

Q • p

(kW)

30 000

600 • ηt

US units

Output f ow Q =

Vg • n • ηv

(US gal/min..)

231

Input torque M=

Vg •

p

(lbf•in)

2 • π • ηm

Input power P =

M • n • π

=

Q • p

(hp)

198 000

1714 • ηt

Vg = Displacement per revolution (cm3/rev)

p= pO - pi (system pressure) (bar)

n= Speed (min-1(rpm))

ηv	=	Volumetric eff ciency
ηm	=	Mechanical eff ciency
ηt	=	Overall eff ciency (ηv • ηm)
Vg	=	Displacement per revolution
		(in3/rev)

p= pO - pi (system pressure) (psi)

n= Speed (min-1(rpm))

ηv	=	Volumetric eff ciency
ηm	=	Mechanical eff ciency
ηt	=	Overall eff ciency (ηv • ηm)

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Based on US units

W = Weight of pump [lb]

L = Distance from mounting f ange [in] to pump center of gravity

MR = GR (W1L1 + W2L2 + ... + WnLn) MS = GS (W1L1 + W2L2 + ... + WnLn)

Where:

MR = Rated load moment N•m MS = Shock load moment N•m

Technical Information

Series 90 Axial Piston Pumps

System Design Parameters

Mounting Flange Loads

Adding tandem mounted auxiliary pumps and/or subjecting pumps to high shock loads may result in excessive loading of the mounting flange.

Applications which experience extreme resonant vibrations or shock may require additional pump support. The overhung load moment for multiple pump mounting may be estimated using the formula below.

Overhung load example

		L3
		L2
		L1
F3	F2	F1
	stage	stage
Third
stage
		P108 511E

Estimated maximum and rated acceleration factors for some typical applications are shown in the table below.

Estimating overhung load moments

Based on SI units

W = Mass of pump kg

L = Distance from mounting f ange to pump center of gravity

(refer to Installation drawings section)

MR = g • GR (W1L1 + W2L2 + ... + WnLn)

MS = g • GS (W1L1 + W2L2 + ... + WnLn)

Where:

MR = Rated load moment N•m MS = Shock load moment N•m g = Gravity 9.81 m/s2

GR = Calculation factor for rated (vibratory) acceleration (G’s)* GS = Calculation factor for maximum shock acceleration (G’s)*

*This factor depends on the application (see next page).

Use these values for a rough load estimation in the absence of specific data.

Typical G loads for various applications

Application	Calculation factor
	Rated (vibratory)	Maximum (shock)
	acceleration GR	acceleration GS
Skid Steer Loader	8	15-20
Trencher (rubber tires)	3	8
Asphalt Paver	2	6
Windrower	2	5

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Technical Information

Series 90 Axial Piston Pumps

System Design Parameters

Typical G loads for various applications (continued)

Application	Calculation factor
	Rated (vibratory)	Maximum (shock)
	acceleration GR	acceleration GS
Aerial Lift	1.5	4
Turf Care Vehicle	1.5	4
Vibratory Roller	6	10
T000 165E

Allowable overhung load moment values are shown in the following table.

Allowable overhung load moments

Frame size	Rated moment (MR)		Shock load moment (MS)
	N•m	lbf•in	N•m	lbf•in
055	1580	14 000	5650	50 000
075	1580	14 000	5650	50 000
100	1580	14 000	5650	50 000
130	3160	28 000	10 730	95 000
180	6070	54 000	20 600	182 000
250	6070	54 000	20 600	182 000

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Technical Information

Series 90 Axial Piston Pumps

Master Model Code

Series 90 Master Model Code Breakdown

R Size M P J

G N F L H T

W

Y

Z

K

S90

S90 Rotation and Size Options

R – Rotation

Code	Description	055	075	100	130	180	250
R	Right hand [CW]	X	X	X	X	X	X
L	Left hand [CCW]	X	X	X	X	X	X

Size

055	55 cc [3.36 in3] max displacement per revolution	X
075	75 cc [4.58 in3] max displacement per revolution		X
100	100 cc [6.10 in3] max displacement per revolution			X
130	130 cc [7.93 in3] max displacement per revolution				X
180	180 cc [10.98 in3] max displacement per revolution					X
250	250 cc [15.26 in3] max displacement per revolution						X

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Technical Information

Series 90 Axial Piston Pumps

Master Model Code

S90 Control Options

M – Controls

Code	Description	055	075	100	130	180	250
CA	Cover plate without feedback link, no control	X	X	X	X	X	X
DC	3 position F-N-R solenoid control (12V, DC) DIN	X	X	X	X	X
	connector
DD	3 position F-N-R solenoid control (24V, DC) DIN	X	X	X	X	X	X
	connector
HF	HDC 2, std. porting, 3, 0-11 bar [44-160 psi]	X	X	X	X	X	X
KA	EDC, MS connector, std. porting, dual coil (14-85 mA)	X	X	X	X	X	X
KN	EDC, MS connector, std. porting, 643 Ohm single coil	X	X	X	X	X	X
	(4-20 mA)
KT	EDC DEUTSCH connector, std. porting, dual coil (14-85	X	X	X	X	X	X
	mA)
KP	EDC, Weatherpack connector, std. porting, dual coil	X	X	X	X	X	X
	(14-85 mA)
MA	MDC	X	X	X	X	X	X
MB	MDC with neutral start switch	X	X	X	X	X	X
FA	NFPE control with 12V Amp connector; proportional	X		X
	solenoid with pressure reducing valve (25 bar)
FB	NFPE control with 24V Amp connector; proportional	X		X	X
	solenoid with pressure reducing valve (25 bar)
FC	NFPE control with 12V Amp connector; proportional	X		X
	solenoid with pressure reducing valve (32 bar)
FD	NFPE control with 24V Amp connector; proportional	X		X
	solenoid with pressure reducing valve (32 bar)
FG	NFPE control with 12V Amp connector; proportional		X	X	X	X
	solenoid with pressure reducing valve (32 bar) fast
	response
FH	NFPE control with 24V Amp connector; proportional		X	X	X	X
	solenoid with pressure reducing valve (32 bar) fast
	response
FK	NFPE control with 12V AMP connector; proportional		X
	solenoid with pressure reducing valve (25 bar)
FL	NFPE control with 24V AMP connector; proportional		X
	solenoid with pressure reducing valve (25 bar)
FM	NFPE control with 12V Amp connector; proportional		X
	solenoid with pressure reducing valve (32 bar) fast
	response
FN	NFPE control with 24V Amp connector; proportional		X
	solenoid with pressure reducing valve (32 bar)

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Technical Information

Series 90 Axial Piston Pumps

Master Model Code

S90 Pressure, Aux Mounting, Ports, Filtration, Displacement Limitation

P – High pressure regulation

Code	Description	055	075	100	130	180	250
1	Pressure limiter for port A and B (140-450 bar)	X	X	X	X	X	X
2	High pressure relief valves for port A and B (90-450	X	X	X	X	X	X
	bar)

J – Auxiliary Mounting Pad

AB	SAE-A with sealed cover, 9 teeth coupling	X	X	X	X	X	X
BB	SAE-B with sealed cover, 15 teeth coupling	X	X	X	X	X	X
BC	SAE-B with sealed cover, 13 teeth coupling	X	X	X	X	X	X
CD	SAE-C with sealed cover, 4 bolt adapter, 14 teeth	X	X	X	X	X	X
	coupling
DE	SAE-D with sealed cover, 13 teeth coupling				X	X	X
EF	SAE-E with sealed cover, 13 teeth coupling					X	X
NN	No auxiliary mounting pad	X	X	X	X	X	X

G – Endcap ports

60	Side ports	X	X		X
80	Twin ports	X	X	X		X	X	X

N – Filtration

D	External charge pump	X	X	X	X	X	X
L	Pressure integral (long filter)	X	X	X	X
P	Pressure integral (short filter)	X	X	X	X
R	Remote pressure	X	X	X	X
T	Remote pressure with SAE 1 1/16 thread ports for					X	X
	high flow
S	Suction filtration	X	X	X	X	X	X

F – Displacement limitation

C	No limiters (180 cc only)					X
M	Limitation on both sides (180 cc only)					X
3	No limiters	X	X	X	X		X
4	Limitation on both sides	X	X	X	X		X
7	No limiters, special servo cylinder side 1 with hard	X	X	X	X	X
	spring (for pumps with NFPE control only)

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Technical Information

Series 90 Axial Piston Pumps

Master Model Code

S90 Shaft and Charging System

L – Shaft Options

Code	Description	055	075	100	130	180	250
C6	Splined shaft, 21 teeth, 16/32 pitch	X	X	X
C7	Splined shaft, 23 teeth, 16/32 pitch		X	X
C8	Splined shaft, 27 teeth, 16/32 pitch				X	X	X
F1	Splined shaft, 13 teeth, 8/16 pitch			X	X	X	X
S1	Splined shaft, 14 teeth, 12/24 pitch	X	X	X
G1	Splined shaft, 25 teeth, 20/40 pitch		X	X
T1	Tapered shaft, 34.925 mm diameter	X	X
T6	Tapered shaft, 38.1 mm diameter		X	X
T8	Tapered shaft, 25.4 mm diameter
T4	Tapered shaft, 44.45 mm diameter				X

H – Charging System

B	11 cc/rev nominal flow	X
C	14 cc/rev nominal flow	X	X
D	17 cc/rev	X	X	X
E	20 cc/rev		X	X
F	26 cc/rev			X	X
H	34 cc/rev				X	X
J	47 cc/rev					X	X
K	65 cc/rev						X
L	External charge pump with internal charge pressure	X	X	X	X	X	X
	relieve valve for units with auxiliary mounting pad
N	External charge pump with internal charge pressure		X	X	X	X	X
	relieve valve for units without auxiliary mounting pad

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Technical Information

Series 90 Axial Piston Pumps

Master Model Code

S90 Control Orifice Options

T – Control Orifice Options for MDC

Code	Inlet P	Drain TA	Drain TB	Servo A	Servo B	055	075	100	130	180	250
00	None	1.6*	1.6*	None	None	X	X	X	X	X	X
03	0.81	1.6*	1.6*	None	None	X	X	X	X	X	X
05	1.37	1.6*	1.6*	None	None	X	X	X	X	X	X
C5	0.81	1.4	1.4	None	None	X	X	X	X	X	X
C6	1.37	1.4	1.4	None	None	X	X	X	X	X	X

* No orifice installed in control,orifice hole in control spool

T – Control Orifice Options for EDC

Code	Inlet P	Drain TA	Drain TB	Servo A	Servo B	055	075	100	130	180	250
00	None	1.3	1.3	None	None	X	X	X	X	X	X
03	0.81	1.3	1.3	None	None	X	X	X	X	X	X
05	1.37	1.3	1.3	None	None	X	X	X	X	X	X
33	0.81	None	None	None	None	X	X	X	X	X	X

T – Control Orifice Options for FNR

Code	Inlet P	Drain T	Servo A	Servo B	055	075	100	130	180	250
G1	None	1.2	None	None	X	X	X	X	X	X
G4	0.46	1.2	None	None	X	X	X	X	X	X
G8	0.66	1.2	None	None	X	X	X	X	X	X
GB	0.81	1.2	None	None	X	X	X	X	X	X
GD	1.57	1.2	None	None	X	X	X	X	X	X

T – Control Orifice Options for HDC

Code	Inlet P	Drain TA	Drain TB	Servo A	Servo B	055	075	100	130	180	250
00	None	1.3	1.3	None	None	X	X	X	X	X	X
003	0.81	1.3	1.3	None	None	X	X	X	X	X	X
005	1.37	1.3	1.3	None	None	X	X	X	X	X	X

T – Control Orifice Options for NFPE

Code	Inlet P	Drain T	Servo A	Servo B	055	075	100	130	180	250
B1	None	1.5	None	None	X	X	X	X	X	X
B2	None	None	1.2	1.2	X	X	X	X	X	X
B6	None	None	None	None		X

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Technical Information

Series 90 Axial Piston Pumps

Master Model Code

S90 Special Hardware and Pressure Settings

W – Special Hardware Features

Code	Description	055	075	100	130	180	250
EEG	Speed ring, no sensor, CP30 + 4.3° valve plate	X	X	X	X
EFC	Speed sensing, Turck connector (KPP x 156), CP15 +		X	X	X
	1.5° valve plate
EFI	Speed sensing Turck connector (KPP x 156) CP30 +	X	X	X	X	X	X
	4.3° valve plate
FAC	Nest T-bar springs CP15 + 1.5° valve plate	X	X	X	X		X
FAD	Nested T-bar springs CP15 + 0.5° valve plate	X	X	X	X
GBA	CP15 + 0.5° valve plate	X	X	X	X
GCA	CP15 + 1.5° valve plate	X	X	X	X	X
GLA	CP30 + 4.3° valve plate, CP30 valve plug	X	X	X	X	X	X
NNN	180cc: CP15 + 0.5° valve plate					X	X
	250cc: CP15 + 1.5° valve plate, nested T-bar springs

Y – High Pressure Setting A

26	260 bar	X	X	X	X	X	X
32	320 bar	X	X	X	X	X	X
35	350 bar	X	X	X	X	X	X
38	380 bar	X	X	X	X	X	X
40	400 bar	X	X	X	X	X	X
42	420 bar	X	X	X	X	X	X

Z – High Pressure Setting B

26	260 bar	X	X	X	X	X	X
32	320 bar	X	X	X	X	X	X
35	350 bar	X	X	X	X	X	X
38	380 bar	X	X	X	X	X	X
40	400 bar	X	X	X	X	X	X
42	420 bar	X	X	X	X	X	X

K – Charge Pressure Setting

20	20 bar	X	X	X	X	X	X
22	22 bar	X	X	X	X	X	X
24	24 bar	X	X	X	X	X	X
26	26 bar	X	X	X	X	X	X
28	28 bar	X	X	X	X	X	X
30	30 bar	X	X	X	X	X	X
32	32 bar	X	X	X	X	X
34	34 bar	X	X	X	X	X

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