Danfoss VSPP User guide

Technical Information

Steering

VSPP Steering Unit

www.danfoss.com

Technical Information

VSPP Steering Unit

Revision history	Table of revisions
	Date	Changed	Rev
	July 2021	Minor corrections to MMC section	0102
	October 2020	First edition	0101

2 | © Danfoss | July 2021

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Technical Information
VSPP Steering Unit
Contents
Overview
A wide range of steering components.....................................................................................................................................	4
Conversion factors...........................................................................................................................................................................	5
Survey of literature with technical data on Danfoss steering components................................................................	5
Steering unit type VSPP
General.................................................................................................................................................................................................	6
VSPP.......................................................................................................................................................................................................	6
Load Sensing dynamic steering unit with built in priority valve, VSPP LS.............................................................	6
Non-reaction.................................................................................................................................................................................	6
Gear set...........................................................................................................................................................................................	7
VSPP versions, overview.................................................................................................................................................................	7
VSPP circuits.......................................................................................................................................................................................	8
Technical data, VSPP LS
Displacement, flow and pressure...............................................................................................................................................	9
Valve functions................................................................................................................................................................................	10
Pilot pressure relief valve; (P-T, Qp) characteristic.............................................................................................................	11
Check valve function in LS..........................................................................................................................................................	11
Pressure drop, P-EF........................................................................................................................................................................	12
Shock valves.....................................................................................................................................................................................	12
Suction valves..................................................................................................................................................................................	13
Check valve in P..............................................................................................................................................................................	13
Weights..............................................................................................................................................................................................	14
Port thread versions
Dimensions
VSPP....................................................................................................................................................................................................	16
VSPP dimensions details..............................................................................................................................................................	17
VSPP: Variants and ordering specifications
VSPP MMC.........................................................................................................................................................................................	18
Variants codes for VSPP MMC....................................................................................................................................................	19

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Technical Information

VSPP Steering Unit

Overview

A wide range of steering components

Danfoss is one of the largest producers in the world of steering components for hydrostatic steering systems on off-road vehicles. Danfoss offers steering solutions both at component and system levels. Our product range makes it possible to cover applications of all types, ranging from ordinary 2 wheel steering (also known as Ackermann steering) to articulated steering, automatic steering (for example, by sensor) and remote controlled steering via satellite. We can offer more than 1,800 different steering units and 250 different priority valves categorized in types, variants and sizes.

Danfoss offers:

For hydrostatic steering systems:

Product type	Displacement	Rated Flow	Steering Pressure
Mini steering units	32 – 100 cm3/rev	max. 20 l/min	max. 150 bar
	[1.95 – 6.10 in3/rev]	[5.28 US gal/min]	[2180 psi]
Steering units	40 – 1200 cm3/rev	max. 100 l/min	max. 240 bar
	[2.44 to 73.2 in3/rev]	[26.4 US gal/min]	[3481 psi]
Priority valves	–	40, 80, 120, 160, 320 l/min	max. 350 bar
		[10.6, 21.1, 31.7, 42.3, 84.5	[5076 psi]
		US gal/min]
Pilot operated flow-	–	240 and 400 l/min [63.4 and	max. 240 bar
amplifiers (factors: 4, 5, 8,		105.7 US gal/min]	[3480 psi]
or 10)
Pilot operated steering	–	max. 100 l/min	max. 250 bar
valves		[26.4 US gal/min]	[3625 psi]

For electrohydraulic steering systems

Product type	Displacement	Rated flow	Steering pressure
Pilot operated steering	-	100 l/min [26.4 US gal/min]	250 bar [3625 psi]
valves
Integrated electrical	100 - 500 cm3/rev	50 l/min [13.2 US gal/min]	210 bar [3045 psi]
operated steering valve	[6.10 - 30.51 in3]
Electrical operated	-	70 l/min [18.5 US gal/min]	210 bar [3045 psi]
steering valve

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Technical Information

VSPP Steering Unit

Overview

Characteristic features for steering units:

•Low steering torque: from 0.5 to 3 N•m in normal steering situations

•Low noise level

•Low pressure drop

•Many types available: Open center Non-reaction, Open center Reaction, Power Beyond, Closed center Non-reaction, Load Sensing, Load Sensing Reaction

•One or more built-in valve functions: relief valve, shock valves, suction valves, non-return valve in P- line and LS-line

•Optional port connections according to ISO, SAE or DIN standards

Characteristics for EH steering systems with OSPE, EHPS, and EHi:

•Possibility of GPS, row sensor, variable steering ratio and joystick steering

•Possibility of manual steering even on very heavy vehicles

•EHPS:

‒High steering pressure requiring smaller cylinders and flow

‒Low pilot pressure and flow giving extremely low noise in the cabin

‒Combined with Danfoss PVG 32 proportional valve

Conversion factors

1 N•m = [8.851 lbf•in]	1 l = [0.264 US gal]
1 N = [0.2248 lbf]	1 bar = [14.5 psi]
1 mm = [0.0394 in]	°F = [1.8°C + 32]
1 cm3 = [0.061 in3]

Survey of literature with technical data on Danfoss steering components

Detailed data on all Danfoss steering components and accessories can be found in our steering component catalogues, which is divided into the following individual sub-catalogues:

General information	Steering components
Technical data on mini steering units	OSPM
Technical data on open center and closed center steering	OSPB, OSPC, and OSPD
units
Technical data on load sensing steering units, priority	OSPB, OSPC, OSPF, OSPD, OSPL, OSPBX, OSPLX, OVPL,
valves and flow amplifiers	OLS, and OSQ
Technical data on load sensing steering unit with	OSPU
amplification
Technical data on steering units	VSP
Technical data on steering units	VSPP
Technical data on hydraulic and electrohydraulic pilot	EHPS, EHPS w. OLS 320, PVE for EHPS and OSPCX
operated steering valves, electrical actuation modules
and appropriate steering units
Technical data on combined sterering unit/	OSPE
electrohydraulic steering valves
Technical data on electrohydraulic steering valves	EHi
Technical data on steering wheel sensors	SASA

For technical information on individual variants, please contact the Danfoss Sales Organization.

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Technical Information

VSPP Steering Unit

Steering unit type VSPP

General

The VSPP is a steering unit with integrated priority valve inside the envelope of a standard steering unit housing.

This brings about a very compact solution minimizing installation space, cost and time.

VSPP is the perfect solution for smaller vehicles like e.g. low horse power tractors, mini wheel loaders and light fork lift trucks, where one gear pump is in use for steering and working hydraulic.

All VSPP products are black painted as standard.

VSPP

All VSPP's are High Spec. for maximum steering pressure 190 bar [2755 psi].

Load Sensing dynamic steering unit with built in priority valve, VSPP LS

The VSPP is a steering unit with integrated priority valve inside the envelope of the standard VSP housing. VSPP LS are all of load sensing dynamictype and so the integrated priority valve is dynamic type.

Spool/sleeve sets for 2 levels of LS dynamic flow are available:

•Standard LS spool/sleeve set: 0.6 - 0.9 l/min [0.16 - 0.24 US gal/min]

•High dynamic LS spool/sleeve set: 1.0 - 1.3 l/min [0.26 - 0.34 US gal/min]

High dynamic is recommended, when extreme fast response is requested, e.g. when unloading working hydraulic load (EF) very rapidly during steering. Trade off with high dynamic is slightly higher energy consumption.

Non-reaction

VSPP’s are non-reaction steering units, where there is no movement of the steering wheel, when the driver is not steering the vehicle. The vehicle keeps the steering direction independent of forces on the steering cylinder.

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Technical Information

VSPP Steering Unit

Steering unit type VSPP

Gear set

The gear set meters the volume of oil/revolution on the steering wheel, cm3/rev. 2 versions of gear set are available for VSPP:

•Low Noise is default for VSPP up to and including 250 cm3/rev. VSPP 315 and VSPP 400 will have gear set with standard profile

•Seal star: reduces slippage, when steering cylinder is at end stroke. Seal star gear sets are available in 50, 70, 80, 100 and 125 cm3/rev.

All seal star gear sets have standard profile.

VSPP versions, overview

The VSP's are available in the x-marked combinations:

Type	Spool/sleeve set		Gear set
	Standard	LS: High dynamic	Low Noise	Seal star
VSPP LS: Load	X		X
Sensing non reaction
	X			X
w. int. Priority valve
		X	X
		X		X

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