Service Manual
PVG 16 and 32 Assembly/Disassembly
Guide
PVG 16, PVG 32
www.danfoss.com
Service Manual
PVG 16 and 32 Service Assembly/Disassembly Guide
Revision history |
Table of revisions |
|
|
|
|
|
|
|
Date |
Changed |
Rev |
|
|
|
|
|
August 2018 |
Corrected typo on page 20 |
0107 |
|
|
|
|
|
November 2017 |
Minor text change |
0106 |
|
|
|
|
|
February 2017 |
Uodated with PVE Series 7 |
0105 |
|
|
|
|
|
May 2014 |
Testing section added, cover image |
AD |
|
|
|
|
|
Apr 2014 |
Converted to Danfoss layout – DITA CMS |
AC |
|
|
|
|
|
Aug 2013 |
Torgue change in dwg, page 19 |
AB |
|
|
|
|
|
Jun 2012 |
First Edition |
AA |
|
|
|
|
2 | © Danfoss | August 2018 |
L1104530 | AX00000133en-US0107 |
Service Manual |
|
PVG 16 and 32 Service Assembly/Disassembly Guide |
|
Contents |
|
General information |
|
PVG general description................................................................................................................................................................ |
4 |
Features of PVG 16 and PVG 32................................................................................................................................................... |
4 |
PVG modules ..................................................................................................................................................................................... |
5 |
PVP, pump side modules overview...................................................................................................................................... |
5 |
PVB, basic modules..................................................................................................................................................................... |
5 |
Actuation modules..................................................................................................................................................................... |
5 |
PVG 16, PVG 32 and Open Circuit Load Sense Example..................................................................................................... |
6 |
Load sensing controls..................................................................................................................................................................... |
7 |
LS control with bleed orifice (do not use with PVG valves)......................................................................................... |
7 |
Integral PC function................................................................................................................................................................... |
7 |
Load sensing system characteristics:................................................................................................................................... |
7 |
PVBS, main spools with pressure compensated control.................................................................................................... |
8 |
Pressure compensated system characteristics................................................................................................................. |
8 |
Typical applications for pressure compensated systems............................................................................................. |
9 |
Remote pressure compensated controls.............................................................................................................................. |
10 |
Remote pressure compensated system characteristics:............................................................................................ |
10 |
Typical applications for remote pressure compensated systems:.......................................................................... |
10 |
Open center PVP............................................................................................................................................................................ |
11 |
Closed center PVP.......................................................................................................................................................................... |
11 |
Sectional view |
|
Safety in Application |
|
Example of a control system for manlift................................................................................................................................ |
13 |
Examples of wiring block diagram..................................................................................................................................... |
15 |
Assembly instructions |
|
PVG 16 and 32 general conditions........................................................................................................................................... |
17 |
Assembly........................................................................................................................................................................................... |
17 |
Testing |
|
PVG 16 and 32 leak test................................................................................................................................................................ |
22 |
Pressure setting after assembly................................................................................................................................................ |
22 |
PVG 16 and 32 function testing................................................................................................................................................ |
23 |
Recommended equipment and hand tools to assemble PVG 16 and PVG 32:.................................................. |
24 |
Test report |
|
Order specifications |
|
© Danfoss | August 2018 |
L1104530 | AX00000133en-US0107 | 3 |
Service Manual
PVG 16 and 32 Service Assembly/Disassembly Guide
PVG is a hydraulic, load-sensing proportional valve, designed for optimal machine performance and maximum design flexibility.
The PVG valve design is based on a modular concept that enables machine designers to specify a valve solution suitable for multiple market segments across multiple applications.
The load independent proportional control valve and high performance actuator technology combined with a low pressure drop design improves the machine performance and efficiency – increasing productivity and reducing energy consumption.
•Load-independent flow control:
‒Oil flow to an individual function is independent of the load pressure of this function
‒Oil flow to one function is independent of the load pressure of other functions
•Good regulation characteristics
•Energy-saving
•Up to 12 basic modules per valve group
•Several types of connection threads
•Low weight
•Compact design and installation
PVG 32 and PVG 16
4 | © Danfoss | August 2018 |
L1104530 | AX00000133en-US0107 |
Service Manual
PVG 16 and 32 Service Assembly/Disassembly Guide
General information
•Built-in pressure relief valve
•Pressure gauge connection
•Versions:
‒Open center version for systems with fixed displacement pumps
‒Closed center version for systems with variable displacement pumps
‒Pilot oil supply for electrical actuator built into the pump side module
‒Pilot oil supply for hydraulic actuation built into the pump side module
‒Versions prepared for electrical LS unloading valve PVPX
•Interchangeable spools
•Depending on requirements the basic module can be supplied with:
‒Integrated pressure compensator in channel P
‒Load holding check valve in channel P
‒Shock/suction valves for A and B ports
‒LS pressure limiting valves individually adjustable for ports A and B
‒Different interchangeable spool variants
‒All versions suitable for mechanical, hydraulic and electrical actuation
The basic module is always fitted with mechanical actuator PVM and PVMD, which can be combined with the following as required:
•Electrical actuator (11 - 32 V ===):
‒PVES – proportional, Super
‒PVEH – proportional, High performance
‒PVEH-F – proportional high performance, Float
‒PVEA – proportional low hysteresis
‒PVEM – proportional, Medium performance
‒PVEO – ON/OFF
‒PVEH-U/PVES-U – proportional, voltage control, 0-10 V
‒PVED-CC – Digital CAN controlled J1939/ISOBUS
‒PVED-CX – Digital CAN controlled CANopen X-tra safety
‒PVEP – PWM voltage controlled (11-32 V)
‒PVHC – High Current actuator for PVG
•PVMR, cover for Mechanical detent
•PVMF, cover for Mechanical Float
•PVH, cover for Hydraulic actuation
© Danfoss | August 2018 |
L1104530 | AX00000133en-US0107 | 5 |
Service Manual
PVG 16 and 32 Service Assembly/Disassembly Guide
General information
The pump receives fluid directly from the reservoir through the inlet line. A screen in the inlet line protects the pump from large contaminants. The pump outlet feeds directional control valves such as PVG-32’s, hydraulic integrated circuits (HIC), and other types of control valves. The PVG valve directs and controls pump flow to cylinders, motors and other work functions. A heat exchanger cools the fluid returning from the valve. A filter cleans the fluid before it returns to the reservoir.
Flow in the circuit determines the speed of the actuators. The position of the PVG valve spool determines the flow demand. A hydraulic pressure signal (LS signal) communicates demand to the pump control. The pump control monitors the pressure differential between pump outlet and the LS signal, and regulates servo pressure to control the swashplate angle. Swashplate angle determines pump flow.
Actuator load determines system pressure. The pump control monitors system pressure and will decrease the swashplate angle to reduce flow if system pressure reaches the PC setting. A secondary system relief valve in the PVG valve acts as a back-up to control system pressure.
Pictorial circuit diagram
Double-ac ting cylinder
K/LFrame Series 45 open circuit axial piston pump with load sensing contro l
PVG 32 multi-sec tion
load sensing contro l valve
Bi-directional gear moto r
Heat exchanger
Reservoir |
Filter |
|
P101 658E
System pressur e
Servo pressur e
Actuator pressur e
Load sense pressur e
Actuator retur n
Suction / case drain / system retur n
6 | © Danfoss | August 2018 |
L1104530 | AX00000133en-US0107 |
Service Manual
PVG 16 and 32 Service Assembly/Disassembly Guide
General information
The LS control matches system requirements for both pressure and flow in the circuit regardless of the working pressure. Used with a closed center control valve, the pump remains in low-pressure standby mode with zero flow until the valve is opened. The LS setting determines standby pressure.
Typical operating curve
Q max
<![if ! IE]><![endif]>Flow
0 0 |
Pressure |
Load sensing circuit
<![if ! IE]><![endif]>PC setting
P101 968E
P101 967
Most load sensing systems use parallel, closed center, control valves with special porting that allows the highest work function pressure (LS signal) to feed back to the LS control.
Margin pressure is the difference between system pressure and the LS signal pressure. The LS control monitors margin pressure to read system demand. A drop in margin pressure means the system needs more flow. A rise in margin pressure tells the LS control to decrease flow.
The load sense signal line requires a bleed orifice to prevent high-pressure lockup of the pump control. Most load-sensing control valves include this orifice. An optional internal bleed orifice is available, for use with control valves that do not internally bleed the LS signal to tank.
The LS control also performs as a PC control, decreasing pump flow when system pressure reaches the PC setting. The pressure compensating function has priority over the load sensing function.
For additional system protection, install a relief valve in the pump outlet line.
•Variable pressure and flow
•Low pressure standby mode when flow is not needed
•System flow adjusted to meet system requirements
•Lower torque requirements during engine start-up
•Single pump can supply flow and regulate pressure for multiple circuits
•Quick response to system flow and pressure requirements
© Danfoss | August 2018 |
L1104530 | AX00000133en-US0107 | 7 |
Service Manual
PVG 16 and 32 Service Assembly/Disassembly Guide
General information
The PC control maintains constant system pressure in the hydraulic circuit by varying the output flow of the pump. Used with a closed center control valve, the pump remains in high pressure standby mode at the PC setting with zero flow until the function is actuated.
Typical operating curve
Q max
<![if ! IE]><![endif]>Flow
0 |
|
|
|
<![if ! IE]> <![endif]>PC setting |
|
|
|
|
|
0 |
Pressur e |
|
P101 166E |
|
|
Simple closed center circuit
P101 965
Once the closed center valve is opened, the PC control senses the immediate drop in system pressure and increases pump flow by increasing the swashplate angle.
The pump continues to increase flow until system pressure reaches the PC setting.
If system pressure exceeds the PC setting, the PC control reduces the swashplate angle to maintain system pressure by reducing flow. The PC control continues to monitor system pressure and changes swashplate angle to match the output flow with the work function pressure requirements.
If the demand for flow exceeds the capacity of the pump, the PC control directs the pump to maximum displacement. In this condition, actual system pressure depends on the actuator load.
For additional system protection, install a relief valve in the pump outlet line.
•Constant pressure and variable flow
•High pressure standby mode when flow is not needed
•System flow adjusts to meet system requirements
•Single pump can provide flow to multiple work functions
•Quick response to system flow and pressure requirements
8 | © Danfoss | August 2018 |
L1104530 | AX00000133en-US0107 |
Service Manual
PVG 16 and 32 Service Assembly/Disassembly Guide
General information
•Constant force cylinders (bailers, compactors, refuse trucks)
•On/off fan drives
•Drill rigs
•Sweepers
•Trenchers
© Danfoss | August 2018 |
L1104530 | AX00000133en-US0107 | 9 |