Danfoss VSPP User manual

Service Manual
Steering unit
VSPP
www.danfoss.com

Revision history Table of revisions
Date Changed Rev
November 2019 First edition 0101
Service Manual
VSPP Steering unit
2 | ©Danfoss | November 2019 AX319758618681en-000101

Safety precautions Safety precautions............................................................................................................................................................................4
VSPP version overview VSPP versions.....................................................................................................................................................................................5
Exploded view, VSPP.......................................................................................................................................................................5
Parts list, VSPP....................................................................................................................................................................................5
Seal kit for VSPP.................................................................................................................................................................................7
Required tools....................................................................................................................................................................................7
VSPP holding tool....................................................................................................................................................................... 7
Assembly tool for dust seal......................................................................................................................................................8
Assembly tool for shaft sea, O-ring / RotoGlyd type...................................................................................................... 8
Additional tools needed...........................................................................................................................................................9
VSPP disassembly Remove shock and relief valves from housing....................................................................................................................11
Remove priority valve parts and P-check from housing..................................................................................................12
Priority valve parts and P-check details............................................................................................................................13
Remove end cover, gear set, cardan shaft, distributor plate, O-rings and valves from gear set end of
housing......................................................................................................................................................................................15
Remove spool/sleeve set from housing................................................................................................................................ 17
Disassemble spool/sleeve set and remove dust seal and shaft from housing........................................................18
VSPP maintenance Cleaning............................................................................................................................................................................................ 19
Inspection and replacement......................................................................................................................................................19
VSPP assembly Assemble spool/sleeve set......................................................................................................................................................... 20
Assemble shaft seal and spool/sleeve set to housing......................................................................................................23
Assemble valve parts, O-rings, distributor plate, cardan shaft, gear set, and end cover to gear set
end of housing........................................................................................................................................................................ 26
Assemble priority valve parts and P-check to housing....................................................................................................28
Assemble shock and relief valves, and dust seal, to housing.........................................................................................29
Assembly details for shock and relief valves, and dust seal......................................................................................30
Testing of VSPP Set-up for testing........................................................................................................................................................................... 32
Shock valves.....................................................................................................................................................................................33
Steering tests...................................................................................................................................................................................33
Start up test......................................................................................................................................................................................33
Pilot relief valve test......................................................................................................................................................................33
Neutral positioning test...............................................................................................................................................................34
Check for external leakage......................................................................................................................................................... 34
Tightening torques for connections
Tightening torques for connections....................................................................................................................................... 35
Service Manual
VSPP Steering unit
Contents
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Safety precautions
Always consider safety precautions before beginning a service procedure. Protect yourself and others
from injury. Take the following general precautions whenever servicing a hydraulic system.
W
Warning
Unintended vehicle or machine movement hazard.
Unintended movement of the machine or mechanism may cause injury to the technican or bystanders.
To prevent uintended movement, secure the machine or disable/disconnect the mechanism while
servicing.
W
Warning
Flammable cleaning solvents
Some cleaning solvents are flammable. To eliminate the risk of fire, do not use cleaning solvents in an
area where a source of ignition may be present.
W
Warning
Fluid under pressure
Escaping hydraulic fluid under pressure can have sufficient force to penetrate your skin causing serious
injury and/or infection. This fluid may also be hot enough to cause burns. Use caution when dealing with
hydraulic fluid under pressure. Relieve pressure in the system before removing hoses, fittings, gauges, or
components. Never use your hand or any other body part to check for leaks in a pressurized line. Seek
medical attention immediately if you are cut by hydraulic fluid.
W
Warning
Personal safety
Protect yourself from injury. Use proper safety equipment, including safety glasses at all times.
W
Warning
Product safety
Steering units are safety components and therefore it is extremely important that the greatest care is
taken when servicing these products. There is not much wear on a steering unit and therefore they
normally outlast the application they are built into. Therefore the only recommended service work on
steering units is:
•Changing shaft seals and O-rings
•Disassemble, clean and assemble if contaminated
•Make hydraulic testing including valve setting.
Service Manual
VSPP Steering unit
Safety precautions
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VSPP versions
VSPP is only available as “Load Sensing dynamic, non-reaction” version.
The exploded view is universal. Some variants are without shock and suction valves.
Exploded view, VSPP
VSPP exploded view
Parts list, VSPP
Item Description Number per
unit
Tightening torque
1 Spool/sleeve set 1 -
2 Housing 1 -
4 Threaded bushing (Screw below surface of
housing) 1 -
5 Ball Ø6.0 mm 1 -
6 O-ring Ø79.4 x Ø2.0 mm 1 -
7 Shaft seal 1 -
9 Dust seal ring 1 -
10 Orifice, LS 1 1 ± 0.1 N•m [8.9 ± 0.9 lbf•in]
12 Cross pin 1 -
13 Cardan shaft 1 -
14 Set of springs 1 -
Service Manual
VSPP Steering unit
VSPP version overview
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Item Description Number per
unit
Tightening torque
16 Ring 1 -
17 Bearing assembly 1 -
21 Spool, priority valve with orifices 1 -
21.1 Spool 1 -
21.2 Orifice, PP 1 1 ± 0.1 N•m [8.9 ± 0.9 lbf•in]
21.3 Orifice, Dynamic 1 3.5 ± 0.5 N•m [31 ± 4.4 lbf•in]
23 Compression spring 1 -
24 Plug with O-ring 1 40 ± 10 N•m [354 ± 88 lbf•in]
24.1 Plug 1 -
24.2 O-ring Ø15.3 x Ø2.4 mm 1 -
25 Plug with O-ring 1 40 ± 10 N•m [354 ± 88 lbf•in]
25.1 Plug 1 -
25.2 O-ring Ø15.3 x Ø2.4 mm 1 -
30 Gearwheel set 1 -
31 Screw 6 30 ± 6 N•m [265 ± 52 lbf•in]
32 Pin bolt screw 1 30 ± 6 N•m [265 ± 52 lbf•in]
34 Distributor plate 1 -
35 Washer 7 -
36 End cover 1 -
37 Model/Code label 1 -
39 O-ring Ø79.4 x Ø2.0 mm 2 -
61 Ball Ø3/16” 2 -
62 Spring with thrust pad for shock valve 2 -
63 Valve seat for shock valve with O-ring 2 6 +0/-1 N•m [59 +0/- 8.9 lbf•in]
63.1 Valve seat for shock 2 -
63.2 O-ring Ø6 x Ø1,5 mm 2 -
64 Adjusting screw for shock valve
with O-ring
2 -
64.1 Adjusting screw 2 -
64.2 O-ring Ø9 x Ø1,5 mm 2 -
75 Plug with O-ring 1 20 ± 5 N•m [177 ± 44 lbf•in]
80 Pin 2 -
81 Ball Ø3/16” 2 -
85 Valve cone, P-check 1 -
86 Compression spring 1 -
87 Screw with O-ring 1 20 ± 5 N•m [177 ± 44 lbf•in]
87.1 Screw 1 -
87.2 O-ring Ø9 x Ø1,5 mm 1 -
90 Valve seat for pilot relief 1 20 ± 3 N•m [177 ± 27 lbf•in]
95 Spring with cone for pilot relief valve 1 -
99 Adjusting screw for pilot relief valve
with O-ring
1 -
99.1 Adjusting screw 1 -
99.2 O-ring Ø9 x Ø2.0 mm 1 -
172 Pin bolt screw for LS check 1 1 ± 0.1 N•m [8.9 ± 0.9 lbf•in]
173 Ball Ø3,5 mm 1 -
Service Manual
VSPP Steering unit
VSPP version overview
6 | ©Danfoss | November 2019 AX319758618681en-000101

Seal kit for VSPP
Spare parts list Code number Item
Seal kit for VSPP 150N4038 6, 7, 9, 24.2, 25.2, 35, 39, 63.2, 64.2,
87.2, 99.2
Required tools
VSPP holding tool
Holding tool dimensions drawing
90±1
ø46±0.5
120±2
2xø15±0.1
5±1
20±1
150±2
100±2
7x51.4°
ø64
7xø15+0.5/-0
1x45°
P301 644
•Material: Appropriate metal or hard plastic.
•This tool is not available from Danfoss.
Service Manual
VSPP Steering unit
VSPP version overview
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Assembly tool for dust seal
Assembly tool for dust seal
0.5x45°
ø26±0.1
min ø40
min 35
100±5
P301 643
•Material: Free cutting steel.
•This tool is not available from Danfoss
Assembly tool for shaft sea, O-ring / RotoGlyd type
Assembly tool for shaft seal, O-ring / Roto Glyd type
•Code number: 11092408.
Service Manual
VSPP Steering unit
VSPP version overview
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Additional tools needed
These tools are not available from Danfoss:
Additional tools needed
•Torque wrench, 0-70 Nm
•Socket spanner for external hexagon: 6, 13, and 22 mm
•Hex keys for internal hexagon: 2, 2.75, 3, 5, 6, and 8 mm
•Screwdrivers: 2 and 12 mm
•Incide circlip pliers
•Magnetic rod
•Hook of max 2mm wire
•Multigrip pliers
•Plastic hammer
Service Manual
VSPP Steering unit
VSPP version overview
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To disassemble VSPP Steering Unit, follow these steps.
Place the unit on the holding tool on the gear set end.
VSPP Steering Unit mounted on holding tool
Service Manual
VSPP Steering unit
VSPP disassembly
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Remove shock and relief valves from housing
To remove shock and relief valve parts from housing, follow these steps.
VSPP shock and relief valve parts
Wrench size and torque
Item Description Wrench size Torque
64 Adjusting screw for shock valve 5 mm Hex key -
63 Valve seat for shock valve 2.75 mm Hex key 6 +0/-1 N•m [59 +0/- 8.9 lbf•in]
99 Adjusting screw for pilot relief
valve 6 mm Hex key -
90 Valve seat for pilot relief valve 6 mm Socket spanner 20 ± 3 N•m [177 ± 27 lbf•in]
1. Screw off the adjusting screws (2x64) using a 5mm Hex key.
O-rings (2x64.2) are fitted to the adjusting screws.
2. Remove the springs with a thrust pad (2x62) using a 2mm flat head screwdriver.
3. Remove the balls (2x61) using a magnet rod.
4. Screw out the valve seat (2x63) using a 2.75mm Hex key.
O-rings (2x63.2) are fitted to the valve seats.
5. Screw out the adjusting screw (99) using a 6mm Hex key.
O-ring (99.2) is fitted to the adjusting screw.
6. Remove the spring with cone (95) using a 2mm flat head screwdriver.
If the cone is not following the spring, remove the cone by using a magnet rod.
7. Remove the valve seat (90) using a 6mm socket spanner.
Service Manual
VSPP Steering unit
VSPP disassembly
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Remove priority valve parts and P-check from housing
To remove priority valve parts and P-check valve parts from housing, follow these steps.
Replace the VSPP unit in the holding tool, so that it’s placed with the column surface on the fixture.
VSPP placed on column surface in the fixing tool
Service Manual
VSPP Steering unit
VSPP disassembly
12 | ©Danfoss | November 2019 AX319758618681en-000101

Priority valve parts and P-check details
VSPP priority valve and P-check parts
Wrench size and torque
Item Description Wrench size Torque
25 Plug with O-ring 22 mm Socket spanner 40 ± 10 N•m [354 ± 88 lbf•in]
21.2 Orifice, PP 2 mm Hex key 1 ± 0.1 N•m [8.9 ± 0.9 lbf•in]
21.3 Orifice, Dynamic 3 mm Hex key 3.5 ± 0.5 N•m [31 ± 4.4 lbf•in]
24 Plug with O-ring 8 mm Hex key 40 ± 10 N•m [354 ± 88 lbf•in]
10 Orifice, LS 2 mm Hex key 1 ± 0.1 N•m [8.9 ± 0.9 lbf•in]
87 Screw with O-ring 6 mm Hex key 20 ± 5 N•m [177 ± 44 lbf•in]
1. Screw off the plug (25) using a 22 mm socket spanner.
O-ring (25.2) is fitted to the plug
2. Remove the spring (23) using a hook.
3. Remove the spool (21) using and incide circlip pliers.
Orifices (21.2) and (21.3) are fitted to the spool
a) Before removing orifices (21.2) and (21.3), fix the spool in a vice with aluminum jaws.
b) Screw out PP orifice (21.2) using a 2mm Hex key.
c) Screw out dynamic orifice (21.3) using a 3mm Hex key.
4. Screw off the plug (24) using an 8mm Hex key.
O-ring (24.2) is fitted to the plug.
5. Screw off the LS orifice (10) from priority spool bore of housing (2) using a 2mm Hex key.
Service Manual
VSPP Steering unit
VSPP disassembly
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6. Screw off the screw (87) using a 6mm Hex key.
O-ring (87.2) is fitted to the screw.
7. Remove the spring (86).
8. Remove the valve cone (85)
Do not remove plug (75). This is a pure blinding plug.
O-ring is not available for this plug in the seal kit.
Service Manual
VSPP Steering unit
VSPP disassembly
14 | ©Danfoss | November 2019 AX319758618681en-000101

Remove end cover, gear set, cardan shaft, distributor plate, O-rings and valves from gear set end of housing
To remove end cover, gear set, cardan shaft, distributor plate, suction-, LS-check- and emergency steer
valves from housing, follow these steps.
End cover, gear set, cardan shaft, distributor plate, O-rings, and valves parts
Wrench size and torque
Item Description Wrench size Torque
31 Screw 13 mm socket spanner 30 ± 6 N•m [265 ± 52 lbf•in]
32 Pin bolt screw 13 mm socket spanner 30 ± 6 N•m [265 ± 52 lbf•in]
4Threaded bushing 12 mm screw driver -
172 Pin bolt screw for LS check 2 mm Hex key 1 ± 0.1 N•m [8.9 ± 0.9 lbf•in]
1. Screw off the six screws (31) using a 13mm socket spanner.
2. Screw off the pin bolt screw (32) using a 13mm socket spanner.
3. Remove the washers (35).
4. Remove the end cover (36) by sliding sideward.
5. Lift the gear wheel set (30) off the unit.
Remove the two O-rings (39) from the gear rim.
6. Remove the cardan shaft (13).
7. Remove the distributor plate (34).
8. Remove the O-ring (6) from housing.
9. Screw out the Pin bolt screw (172) using a 2mm Hex key.
10. Drag out the suction pins (80) using a hook.
It may be needed to line up the suction pin in the thread bore with a 2mm screw driver before it will
be possible to insert the hook into the cross hole of the suction pins.
11. Screw out threaded bushing (4) using a 12mm screw driver.
Service Manual
VSPP Steering unit
VSPP disassembly
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12. Lift off the VSPP housing from holding tool and let balls (5), (2x81), and (173) fall out.
Hold in hand to remove balls from gear set end
Service Manual
VSPP Steering unit
VSPP disassembly
16 | ©Danfoss | November 2019 AX319758618681en-000101

Remove spool/sleeve set from housing
1. Place the VSPP housing on the work pbench on the port face.
VSPP placed on port face on work bench
2. Determine if cross pin (12) in spool/sleeve set (1) is parallel to port face. If not, insert cardan shaft (13),
and rotate spool/sleeve set (1) to position cross pin (12) correctly.
This is needed to make sure that cross pin (12) cannot fall into ring channels in housing (2) when
pressing out the spool/sleeve set.
3. Press out the spool/sleeve set (1) from housing (2). Cross pin (12), ring (16), set of spinrgs (14), and
bearing assembly (17) will follow the spool/sleeve set.
4. Take the bearing races and needle bearing (17) from the spool/sleeve set (1).
The outer bearing (17) race can sometimes "stick" in the housing. Therefore check that it has come
out.
Service Manual
VSPP Steering unit
VSPP disassembly
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Disassemble spool/sleeve set and remove dust seal and shaft from housing
1. Press out the cross pin (12).
2. Remove the ring (16).
3. Carefully press out the spool of the sleeve (1).
4. Press the set of neutral springs (14) out of the slot of the spool.
5. Remove the dust seal (9), and the shaft seal (7), carefully with a 2mm screw driver.
The VSPP steering unit is now completely dismantled.
Disassembled VSPP Steering unit
Service Manual
VSPP Steering unit
VSPP disassembly
18 | ©Danfoss | November 2019 AX319758618681en-000101

Cleaning
Clean all parts carefully in Shellsol K or similar cleaning fluid.
Inspection and replacement
Replace all seals and washers.
Place new O-rings from seal kit on plugs (24.1, 25.1, 64.1, 87.1, 99.1) and on seats (63.1).
Check all parts carefully and make any replacements as necessary.
Service Manual
VSPP Steering unit
VSPP maintenance
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Assemble spool/sleeve set
To assemble spool/sleeve set with springs, cross pin, and ring, folow these steps.
1. Place the curved springs between the flat ones and press them into place.
Press springs into place
Configuration of spring set (14):
There can be different numbers of curved springs, depending on configuration of spring set.
There can be 2, 4, or 6 curved springs.
Spring configuration
Some spool and sleeve sets for VSPP must be positioned correctly, relative to each other. Small marks
are present of both the spool and sleeve, close to one of the slots for the spring set.
Most spool and sleeve sets for VSPP have no marks, so those can be positioned relative to each other,
in either of the 2 positions possible.
Service Manual
VSPP Steering unit
VSPP assembly
20 | ©Danfoss | November 2019 AX319758618681en-000101