Open circuit axial piston pumps
frame k and l (37 pages)
Summary of Contents for Danfoss 90 Series
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MAKING MODERN LIVING POSSIBLE Service Manual Series 90 Pumps powersolutions.danfoss.com...
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Revision history Table of revisions Date Changed August 2015 edits to Aux Pad minor repair 0101 December 2014 Danfoss layout June 2012 minor edits December 2011 minor edits April 2008 page 70 correction to bolt torques October 2007 First printing...
General instructions..................................5 Safety precautions....................................6 Unintended machine movement............................6 Flammable cleaning solvents..............................6 Fluid under pressure.................................. 6 Personal safety..................................... 6 Symbols used in Danfoss literature............................7 Design........................................7 The system circuit.....................................8 The basic closed circuit................................8 Case drain and heat exchanger..............................9 Operation Charge pump....................................11 Charge relief valve..................................
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Service Manual Series 90 Pumps Contents Transmission operates normally in one direction only....................25 System will not operate in either direction.......................... 26 Low motor output torque................................26 Improper motor output speed..............................26 System noise or vibration................................27 System response is sluggish..............................27 Adjustments Standard procedures, inspections, and adjustments.......................
A worldwide network of Danfoss Global Service Partners (GSPs) is available for major repairs. Danfoss trains GSPs and certifies their facilities on a regular basis. You can locate your nearest ASC using the distributor locator at www.DanfossPower Solutions.com.
Service Manual Series 90 Pumps Introduction For repair, place the unit in a stable position with the shaft pointing downward. It will be necessary to secure the pump while removing and torquing end covers, controls, and valves. Safety precautions Always consider safety precautions before beginning a service procedure. Protect yourself and others from injury.
The legend above defines each symbol and explains its purpose. Design Danfoss Series 90 closed circuit piston pumps convert input torque into hydraulic power. The input shaft transmits rotational force to the cylinder block. Bearings support the input shaft at the front and rear of the pump.
Service Manual Series 90 Pumps Introduction Basic closed circuit diagram Reservoir Input Output Flow (Bi-directional) Case drain line P104 120E Case drain and heat exchanger The pump and motor require case drain lines to remove hot fluid from the system. The topmost port drains the motor to ensure the case remains full of fluid.
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Service Manual Series 90 Pumps Introduction Pump schematic P104 126E 520L0818 • Rev 0101 • August 2015...
Service Manual Series 90 Pumps Operation Charge pump The charge pump is necessary to supply cool fluid to the system, to maintain positive pressure in the main system loop, to provide pressure to operate the control system, and to make up for internal leakage. Charge pressure must be at its specified pressure under all conditions to prevent damage to the transmission.
Service Manual Series 90 Pumps Operation Multi-function valve High pressure Pressure limiter housing Check valve relief / check valve poppet poppet Pressure limiter lock nut Pressure limiter adjustment screw Bypass Bypass actuator Pressure limiter P104 122E valve poppet Some multi-function valves do not include a pressure limiter valve Pressure limiter and high pressure relief valves Series 90 pumps have a sequenced pressure limiting system and high pressure relief valves.
Service Manual Series 90 Pumps Operation Speed sensors An optional speed sensor can provide unit speed information. The sensor reads a magnetic ring on the unit’s cylinder block. See the corresponding section to locate, install, and adjust the speed sensor. Filtration options Series 90 pumps may have either suction or charge pressure filtration to filter the fluid entering the circuit.
Service Manual Series 90 Pumps Operation overrides the control by reducing the pressure to the displacement control. As the control pressure reduces, the internal forces rotating the swashplate overcome the force of the servo pistons and decreases the pump’s displacement. POR-Valve (180 frame size only) To control Multi-function valve...
Service Manual Series 90 Pumps Operation Electric displacement control (EDC) The electric displacement control uses a Pressure Control Pilot (PCP) valve to modulate pressure balance across the spring-centered four-way servo valve. The PCP valve converts a DC electrical input signal to a hydraulic signal.
Maximum speed is the highest operating speed permitted. Exceeding maximum speed reduces product life and can cause loss of hydrostatic power and braking capacity. Never exceed the maximum speed limit under any operating conditions. When determining speed limits for a particular application see Danfoss publication BLN-9884 Pressure and speed limits. Warning Unintended vehicle or machine movement hazard Exceeding maximum speed may cause a loss of hydrostatic drive line power and braking capacity.
Service Manual Series 90 Pumps Operating parameters pressure setting is referenced to case pressure. Charge pressure is the differential pressure above case pressure. Charge inlet pressure At normal operating temperature charge inlet pressure must not fall below rated charge inlet pressure. Minimum charge inlet pressure is only allowed at cold start conditions.
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Change filters whenever the fluid is changed or when the filter indicator indicates a filter change. Replace all fluid lost during filter change. For detailed filtration information, see Danfoss publication 520L0463 Fluids and Filtration. For information on biodegradable fluids see Danfoss publication 520L0465 Biodegradable Hydraulic Fluids.
Service Manual Series 90 Pumps Technical specifications Overview Specifications and operating parameters for pumps appear here for reference. Features and options Model Series 90 Pumps Mount SAE B, SAE C and E (SAE J 744) Pump type Axial piston type Rotation Bidirectional Installation position...
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Service Manual Series 90 Pumps Technical specifications Parameter Unit Minimum Continuous Maximum Viscosity /sec (cSt) 12-60 1600 [SUS] [47] [66-278] [7500] Temperature °C [°F] -40 [-40] 104 [220] 115 [240] Cleanliness ISO 4406 Class 22/18/13 or better Filtration efficiency suction filtration β35-44=75 (β10≥2) charge filtration β15-20=75 (β10≥10)
Service Manual Series 90 Pumps Initial start-up procedure General Follow this procedure when starting-up a new pump installation or when restarting an installation in which the pump was removed. Warning Unintended movement of the machine or mechanism may cause injury to the technician or bystanders. To protect against unintended movement, secure the machine or disable/disconnect the mechanism while servicing.
Service Manual Series 90 Pumps Pressure measurement Required tools You can perform the service procedures described in this manual using common mechanic’s tools. Special tools, if required are shown. Use calibrated pressure gauges to ensure accuracy. Use snubbers to protect pressure gauges. Port locations and gauge installation The following sections list the ports for each type of hydraulic unit.
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Service Manual Series 90 Pumps Pressure measurement Pump with side port end cap and manual displacement control Servo / displacement Case drain cylinder pressure port L1 gauge port M4 Servo / displacement System pressure cylinder pressure port B gauge port M5 External control pressure System pressure supply port X3...
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Service Manual Series 90 Pumps Pressure measurement Pump with side port end cap and remote pressure filtration / Pump with side port end cap and integral pressure filtration Charge pressure gauge port M6 Port E (before the filter) (from filter) Port D (to filter) Charge pressure...
Service Manual Series 90 Pumps Troubleshooting Overview This section provides general steps to follow if certain undesirable system conditions occur. Follow the steps in a section until you solve the problem. Some of the items are system specific. For areas covered in this manual, we reference the section.
Service Manual Series 90 Pumps Troubleshooting System will not operate in either direction Item Description Action Oil level in reservoir Insufficient hydraulic fluid to supply system loop Fill reservoir to proper level. Input to pump control Input to control module is operating improperly Check control input and repair replace as necessary.
Service Manual Series 90 Pumps Troubleshooting System noise or vibration Item Description Action Oil in reservoir Insufficient hydraulic fluid will lead to cavitation. Fill reservoir to proper level. Air in system Air bubbles will lead to cavitation. Look for foam in reservoir. Check for leaks on inlet side system loop and repair.
Service Manual Series 90 Pumps Adjustments Standard procedures, inspections, and adjustments Before working on the pump, clean the outside of the pump. Caution Contamination can damage internal components and void your warranty. Take precautions to ensure system cleanliness when removing and reinstalling system lines. 1.
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3. Earlier production Series 90 pumps have a shim adjustable charge pressure relief valve. Shim kits are available from Danfoss. Remove the plug using a 1in hex wrench and exchange shims behind the spring to adjust charge pressure. Torque plug to 68 N•m [50 lbf•ft].
Service Manual Series 90 Pumps Adjustments 6. Once you achieve the desired charge pressure setting, remove the gauges and plug the ports. Multi-function valve pressure adjustment You accomplish adjustment of the pressure limiter setting and the high pressure relief valve (HPRV) setting simultaneously.
Service Manual Series 90 Pumps Adjustments 6. Return the pump to its neutral (zero flow) position and adjust the pressure limiter setting by rotating the pressure adjusting screw with an internal hex wrench. Clockwise rotation of the pressure adjustment screw increases the pressure setting, and counterclockwise rotation decreases the pressure setting.
Service Manual Series 90 Pumps Adjustments Displacement limiter adjustment You can limit the maximum displacement in either direction. 1. Loosen the lock nut (F212) while holding the adjusting screw (F213) steady. 2. Rotate the adjusting screw some amount (using information in the following table). Rotating the adjusting screw clockwise decreases the maximum displacement of the pump while rotating the adjusting screw counterclockwise increases the maximum displacement.
Service Manual Series 90 Pumps Adjustments Non-linear manual displacement control (MDC) A centering spring, located on the control input shaft, locates the control shaft in its neutral position. A bias spring on the control spool maintains a force on the spool and the control linkage to eliminate free- play in the linkage.
Service Manual Series 90 Pumps Adjustments MDC Neutral start switch (NSS) adjustments The Neutral Start Switch (NSS) provides a means to prevent the system prime mover from starting while the pump control handle is in-stroke. When the control input shaft is in its neutral position, the switch pin engages a slot on the eccentric cam attached to the control shaft.
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Service Manual Series 90 Pumps Adjustments Neutral start switch adjustment requirements NSS deadband Control shaft (switch closed, ON) (free-play) Control deadband (neutral) Total control shaft rotation Control shaft P104 147E Neutral start switch eccentric plug adjustment (condition i) Center the NSS deadband and the control deadband in relation to each other. Since you cannot adjust the position of the control deadband, you must adjust the position of the NSS deadband to match it.
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Service Manual Series 90 Pumps Adjustments NSS with eccentric plug Switch lock nut Eccentric plug Switch pin Special lock nut Neutral start switch for eccentric plug Special lock nut for eccentric plug Eccentric plug Control mounting surface Switch pin View B-B (switch and lock nut removed) P104 150E 1.
Service Manual Series 90 Pumps Adjustments Caution Do not turn the eccentric plug into or out of the housing beyond specifications. 7. Once the switch is correctly adjusted, hold the switch in place and tighten the lock nut to 27 N•m [20 lbf•ft] torque.
Service Manual Series 90 Pumps Adjustments Warning The following procedure may require the vehicle/machine to be disabled (wheels raised off the ground, work function disconnected, etc.) while performing the procedure in order to prevent injury to the technician and bystanders. Take necessary safety precautions before moving the vehicle/machine. Checking switch continuity Servo pressure gauge port M5 0 - 50 bar [0 - 1000 psi]...
Service Manual Series 90 Pumps Adjustments Make this adjustment on a test stand or on the vehicle/machine with the prime mover operating. Warning The following procedure may require the vehicle/machine to be disabled (wheels raised off the ground, work function disconnected, etc.) while performing the procedure in order to prevent injury to the technician and bystanders.
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Service Manual Series 90 Pumps Adjustments 3. Turn the sensor counterclockwise (CCW) 1/2 turn (180°) to establish the nominal gap of 0.71 mm [0.028 inch]. 4. Then turn the sensor clockwise (CW) until the wrench flats on sensor body are positioned at a 22° angle to the pump shaft center line.
Service Manual Series 90 Pumps Minor repair Standard procedures Removing the pump Before working on the pump, clean the outside of the pump. If the pump has an auxiliary pump attached, remove both pumps as a single unit. Tag and cap all hydraulic lines as they are disconnected and plug all open ports to ensure that contamination does not enter the system.
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Service Manual Series 90 Pumps Minor repair 6. Remove shaft (L100) and roller bearing assembly (L10) from pump. You can transfer the bearing assembly to the new shaft. 7. Using snap-ring pliers, remove the retaining ring (L20) that secures the roller bearing assembly. Remove the roller bearing assembly.
Service Manual Series 90 Pumps Minor repair 4. Lubricate and install a new O-ring (L50) on the seal carrier. Lubricate the seal with clean petroleum jelly. 5. Assemble the seal carrier and seal over the shaft and into the housing bore. Install the retainer plate (if used).
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Service Manual Series 90 Pumps Minor repair 4. Remove and discard O-ring (P02). Multi-function valves are sold as complete units only. You may purchase O-rings separately. 5. The poppet seat section is pressed over a lip. Place the cartridge in a vise and pry the poppet seat (P12) off with an appropriate tool.
Service Manual Series 90 Pumps Minor repair 2. Install poppet seat (P1). 3. Install retaining ring (P22). 4. If previously removed, lubricate and install O-ring (P19). 5. If previously removed, reassemble and install bypass actuator (P14). Torque to 40 N•m [30 lbf•ft]. 6.
Service Manual Series 90 Pumps Minor repair Pressure override valve components Screws Pressure override valve O-rings E101 079E Charge pressure relief valve The charge pressure relief valve is shim adjustable (early models) or screw adjustable (late models). Screw adjustable charge relief valve is shown. Removal 1.
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Service Manual Series 90 Pumps Minor repair Reassembly Install the poppet (K80) and spring (K70). For shim adjustable valves, install the shims and plug, torque to 68 N•m [50 lbf•ft]. For screw adjustable valves, install the plug with its lock nut, aligning the marks made at disassembly, and torque the lock nut to 52 N•m [38 lbf•ft].
Service Manual Series 90 Pumps Minor repair Adding an Auxiliary pad to a pump previously without one 1. Remove the six retaining screws (H80) and remove the retaining plate (H70) and cover plate (J15). Remove the cover plate P108928 2. Observe the alignment pin (H40). If the pin remains in the charge pump, leave it in place. If the pin comes out with the cover plate, reinstall it in the geroter eccentric.
Service Manual Series 90 Pumps Minor repair 2. Take care to assure the surfaces are clean and free of any foreign material or paint prior to installing the auxiliary pad. Caution Do not allow the force of the cylinder block spring and swashplate leveler springs to separate the end cap from the pump housing.
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Current charge pump configuration E101082 Refer to appropriate Danfoss Series 90 service parts manual for earlier charge pump configurations. 4. Remove the charge pump coupling (H50) and charge pump drive key (H60). 5. Remove the charge pump gerotor assembly (H05).
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Service Manual Series 90 Pumps Minor repair The orientation of the gerotor assembly outer eccentric ring and the location of the alignment pin in the end cap determine the charge pump rotation.. Do not mix charge pump parts from different production periods. Always install as a complete assembly. Orienting alignment pin Discharge Discharge...
Service Manual Series 90 Pumps Minor repair 12. Install the charge pump cover retainer (H70) and the six internal hex screws (H80). Torque the screws per the table at the right.. Retainer screw torque Frame size Torque 030 – 100 16 N•m [11.85 lbf•ft] 130 –...
Service Manual Series 90 Pumps Minor repair Pump controls cover plate M90 (x6) 5 mm 16 N•m [12 lbf•ft] Seal washer location (42, 180, 250 cc) P106 184E Displacement control orifices 1. Remove the control assembly as described in the instructions for the specific displacement control. 2.
Service Manual Series 90 Pumps Minor repair 2. The orifice check valve is located in the control assembly, at the surface of the pump housing face. Remove the spring retainer and spring from the orifice check valve cavity and then remove the orifice check valve.
Service Manual Series 90 Pumps Minor repair Manual displacement control (MDC) Removal 1. Thoroughly clean external surfaces prior to removal of control. 2. Using a 5 mm internal hex wrench, remove the six control mounting screws (M90). Remove the control (M1) (with orifice check valve (T40) and spring (T30)) and control gasket (M11) from the housing.
Service Manual Series 90 Pumps Minor repair Hydraulic and electric displacement controls Removal 1. Thoroughly clean external surfaces prior to removal of control. 2. Using a 5 mm internal hex wrench, remove the six control mounting screws (M90). Remove the control (M1) (with orifice check valve (T40) and spring (T30)) and control gasket (M11) from housing.
Service Manual Series 90 Pumps Minor repair 4. Align the control gasket and install the screws. Torque the screws to 16 N•m [12 lbf•ft]. Install a sealing washer under the head of any mounting screws that are installed into through holes in the housing.
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Service Manual Series 90 Pumps Minor repair 3. Using a 5 mm internal hex wrench, remove the six adapter plate mounting screws (M90). Remove the adapter plate and gasket (M11) from the housing. Discard the gasket. Caution Protect exposed surfaces and cavities from damage and foreign material. Inspection Inspect the orifice installed between the valve and adapter plate.
Service Manual Series 90 Pumps Minor repair FNR removal/installation W702 (x4) 5 mm 5.4 N•m [4 lbf•ft] W701A M90 (x6) 5 mm 16 N•m [12 lbf•ft] M900 Seal washer location (42, 180, 250 cc) P106 185E Displacement control filter screens If the pump is equipped with control filter screens in the pump housing (late production), press them into position (with the rounded edge of the filter screens facing the control) until they are flush to 2.0 mm [0.08 inch] below the surface of the housing.
Service Manual Series 90 Pumps Minor repair Filter screen installation P106 690E Speed sensor Removal 1. Loosen the lock nut using a 11/16 in hex wrench. 2. Unscrew the speed sensor (B83) from the pump housing. Remove and discard the O-ring (B83A). Reassembly 1.
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Service Manual Series 90 Pumps Minor repair Typical location of speed sensor B83 O-ring plug 40 N•m [30 lbf•ft] B83A B83A 40 N•m [30 lbf•ft] E101 095E 520L0818 • Rev 0101 • August 2015...
Service Manual Series 90 Pumps Torque chart Item Fastener Frame size Wrench size Torque P2B1/ Multi-function valve 030-100 1-1/4 in hex 89 N•m [66 lbf•ft] P2A1 130-250 1-5/8 in hex 210 N•m [155 lbf•ft] Plug size and torque chart If any plugs or fittings are removed from the pump during servicing,install and torque as indicated in the accompanying table.
Service Manual Series 90 Pumps Torque chart Fasteners and plugs Fastener and plug locations B70, B72 O-ring plug 9/16-18 G90 End cap screw J80 Auxilliary pad / M90 Control bolt end cap screw H80 Charge pump retaining screw L70 Shaft seal retaining screw G53, G54 O-ring plug 9/16-18...
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Service Manual Series 90 Pumps 520L0818 • Rev 0101 • August 2015...
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Phone: +86 21 3418 5200 Danfoss can accept no responsibility for possible errors in catalogues, brochures and other printed material. Danfoss reserves the right to alter its products without notice. This also applies to products already on order provided that such alterations can be made without changes being necessary in specifications already agreed.
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