High pressure liquids and gases are potentially hazardous. Energy stored in these liquids and gases
can be released unexpectedly and with extreme force. High pressure systems should be assembled and
operated only by personnel who have been instructed in proper safety practices.
Information in this document is subject to change without notice. No part of this document may be reproduced or
transmitted in any form or by any means, electronic or mechanical, for any purpose, without the express written
permission of DH Instruments, a Fluke Company 4765 East Beautiful Lane Phoenix AZ 85044-5318 USA.
DH Instruments makes sincere efforts to ensure accuracy and quality of its’ published materials; however, no
warranty, expressed or implied, is provided. DH Instruments disclaims any responsibility or liability for any direct or
indirect damages resulting from the use of the information in this manual or products described in it. Mention of any
product or brand does not constitute an endorsement by DH Instruments of that product or brand. This manual was
originally composed in English and was subsequently translated into other languages. The fidelity of the translation
cannot be guaranteed. In case of conflict between the English version and other language versions, the English
version predominates.
DH Instruments, DH, DHI, OPG1, RPM3, PG7000 and CalTool are trademarks, registered and otherwise, of DH
Instruments, a Fluke Company.
Swagelok is a registered trademark of the Swagelok Company.
Teflon is a registered trademark of the 3M Corporation.
1.3.1 FRONT PANEL ..............................................................................................................................................2
1.3.3 SYSTEM SCHEMATIC ..................................................................................................................................4
2.3.1 PREPARING FOR OPERATION ...................................................................................................................7
2.3.1.1 SET UP THE OPG1 ...................................................................................................................................7
2.3.1.2 CONNECT PNEUMATIC POWER (DRIVE AIR)........................................................................................7
2.3.1.3 MAKE HYDRAULIC PRESSURE INTERCONNECTIONS ......................................................................11
2.4 POWER UP AND VERIFICATION .........................................................................................................13
2.4.1 APPLY PNEUMATIC POWER (DRIVE AIR) ...............................................................................................13
2.4.2 ADJUST HYDROPNEUMATIC PUMP DRIVE AIR PRESSURE................................................................. 13
2.4.3 CHECK PROPER OPERATION OF HYDROPNEUMATIC PUMP AND LEAK CHECK.............................13
2.4.3.1 STEP ONE: PURGING AIR FROM THE HYDRAULIC PUMP CIRCUIT ................................................13
2.4.3.2 STEP TWO: GENERATING A PRESSURE............................................................................................ 14
2.4.3.3 PRIMING THE HYDROPNEUMATIC PUMP BY SYRINGE INJECTION.................................................15
2.4.3.4 INTERNAL PURGE OF HYDROPNEUMATIC PUMP .............................................................................15
2.4.4 PRECAUTIONS TO TAKE BEFORE GENERATING PRESSURE/SAFETY
2.5 SHORT TERM SHUT-DOWN ................................................................................................................17
2.6 LONG TERM STORAGE AND SHIPPING.............................................................................................17
CONSIDE RATI ON S................................................................................................................................. 16
3. GENERAL OPERATION ..................................................... 19
Table 4. DHI Authorized Service Providers............................................................................................... 34
F
IIGGUURREES
F
Figure 1. Front Panel................................................................................................................................... 2
Figure 2. Front and Side Views with Dimensions ....................................................................................... 3
Figure 3. System Schematic ....................................................................................................................... 4
Figure 4. Configuring Pneumatic Power Connections .............................................................................. 11
Figure 5. Connecting OPG1 to PG7302 or RPM3 .................................................................................... 12
Figure 7. System Schematic .....................................................................................................................20
Figure 8. Front Panel................................................................................................................................. 21
Figure 9. PDVV Position Indicator............................................................................................................. 23
Figure 10. Fluid Head Level When Vented, INLET Valve Open .............................................................. 24
This manual provides the user with the information necessary to operate an OPG1 Hydraulic Pressure
Generator/Controller. It also includes a great deal of additional information provided to help you optimize
OPG1 use and take full advantage of its many features and functions.
FOR THOSE OF YOU WHO “DON’T READ MANUALS”, GO DIRECTLY TO SECTION 2.3 TO SET
UP YOUR OPG1. THEN GO TO SECTION 4.3. THIS WILL GET YOU RUNNING QUICKLY WITH MINIMAL
RISK OF CAUSING DAMAGE TO YOURSELF OR YOUR OPG1. THEN… WHEN YOU HAVE QUESTIONS
OR START TO WONDER ABOUT ALL THE GREAT FEATURES YOU MIGHT BE MISSING, GET INTO
THE MANUAL!
(CAUTION) is used throughout the manual to identify user warnings and cautions.
(NOTE) is used throughout the manual to identify operating and applications advice and
The OPG1 Hydraulic Pressure Generator/Controller is a stand alone, pressure generating and controlling
component intended to be used as the pressure source and means of pressure adjustment in hydraulic
calibration and test systems. It is capable of both generating and precisely adjusting pressure from
atmosphere to 200 MPa (30 000 psi).
OPG1 combines the versatility, speed and reliability of direct operator control with the convenience and
effort-free operation of automation. It is the standard pressure generating and control component in a
DHI PG7302 piston gauge system or combined with an RPM3 digital pressure monitor to configure a
transfer standard based calibration system.
OPG1 includes an on-board hydropneumatic pump to fill the system under test and generate pressures
up to 200 MPa (30 000 psi). Two highly progressive, half-turn needle valves control the inlet of pressure
from the pump to increase pressure and outlet back to the reservoir to decrease pressure. Very fine
pressure adjustment and generation of small pressure excursions is accomplished using a Pneumatically
Driven Variable Volume (PDVV) with push button control. Pneumatic power (drive air) of up to 850 kPa
(120 psi) is needed to drive the hydropneumatic pump and PDVV.
1.2SPECIFICATIONS
Electrical Power Requirements
Pneumatic Power Requirements
The exact OPG1 system installation is affected by the components other than the OPG1 that make up the
system. This generally includes a pressure measuring reference such as a transfer standard or piston
gauge.
When selecting and preparing a site to set up the OPG1 system, the following should be considered:
•Bench Stability: The OPG1 weighs about 27 kg (60 lb). Consider its weight and that of other
components, including possible items to be tested, when selecting a bench.
•Location of Other Components: Plan the space required and a convenient layout for the complete
system in which OPG1 is the pressure generation/control component. OPG1 has TEST ports on both
its right and left rear sides to allow it to be placed to the right or left in the setup. Select
interconnecting tubing and fittings rated to handle the maximum pressures that will be generated.
OPG1 hydraulic fittings are all DH500 (equivalent to AE F250C, HIP HF4, etc.). The female DH500
fittings are delivered with glands, nuts and plugs installed. Collars are included in the accessory kit.
If you do not plan to use OPG1’s top TEST port, consider where a device or system under test (DUT)
will be connected.
If the OPG1 is to be used with a DHI RPM3 or PG7302 reference device, OPG1 accessories include
the hardware necessary for setting up in a standard configuration (see Sections 2.1.2 and 2.3.1.3,
Connecting to a DHI RPM3 or PG7302 Using Standard OPG1 Interconnection Accessories).
•Pressure Supply: Plan the pneumatic power to OPG1. This requires an air or nitrogen source: See
Section 2.3.1.2. for detailed requirements. The connections are 1/4 in. NPT female.
•System Interconnections: Plan the interconnections between OPG1 and other components in the
system. Minimizing the volume and maximizing the mass of all interconnecting elements will reduce
pressure generation and stabilization time (see Section 2.3.1.3).
ALWAYS use external tubing and fittings rated for pressures equal to or greater than the
maximum pressure that OPG1 will be used to generate.
Before setting up the OPG1, see Section 2.2 for general information on site requirements.
To prepare an OPG1 for check out and operation:
• Set up the OPG1 (see Section 2.3.1.1).
• Connect pneumatic power (see Section 2.3.1.2).
• Make the system hydraulic pressure interconnections (see Section 2.3.1.3).
2.3.1.1 SET UP THE OPG1
To set up the OPG1 proceed as follows:
n Place the OPG1 platform on the site table in the proper orientation with the
front panel controls conveniently accessible.
o Fill tank with oil if necessary. Back off the tank cover until a gap for oil
passage can be seen between the DUT connection shaft and the cover.
Pour in oil to just under the overflow tube (see Section 4.2).
p Leave tank cover open to allow oil to drain from the DUT connection and air
to escape when venting oil back to tank.
q Install the mat delivered with accessories on top front of OPG1 around oil tank.
2.3.1.2 CONNECT PNEUMATIC POWER (DRIVE AIR)
OPG1 requires pneumatic power to drive two different components:
the hydropneumatic pump and the pneumatically driven variable volume (PDVV)
(see Section 3.1, Figure 7).
The drive air supply to these two components may be common on one
connection for both components or two independent connections may be
required depending on the maximum oil pressure to be generated and drive air
pressure supply available (see Section 3.1, Figure 7). The requirements for the
two different components are summarized in Table 2. To determine whether
your application and resources allow a single connection or require two
independent connections, see Table 2 to characterize your application and then
follow the recommendations in Section 2.3.1.2,
Connections?. Finally, follow the instructions in Section 2.3.1.2, Making Two
Independent Pneumatic Power Connections for two independent drive
air connections and
common drive air connection.
Making a Single Pneumatic Power Connection for a single,
One or Two Pneumatic Power
OPG1 is delivered configured for two independent drive air connections as
described in Section 2.3.1.2, Making Two Independent Pneumatic Power
Connections. This is the recommended configuration.
OPG1™ OPERATION AND MAINTENANCE MANUAL
Table 2. Pneumatic Power (Drive Air) Requirements
INTERNAL
COMPONENT
Hydropneumatic
Pump
PDVV 70 MPa (10 000 psi):
DRIVE AIR
PRESSURE NEEDED
(Hydraulic output
pressure/400)
+ 100 kPa (15 psi)
550 kPa (80 psi)
140 MPa (20 000 psi):
700 kPa (100 psi)
200 MPa (30 000 psi):
850 kPa (120 psi)
MINIMUM
FLOW
50 slm
(1.8 scfm)
*This is fairly
high flow.
200 sccm
(< 0.01 scfm)
*This is very
low flow.
LUBRICATION
REQUIRED
No No
No Yes
CLEANLINESS
CRITICAL
One or Two Pneumatic Power Connections?
Two pneumatic power connections are needed if:
•The high flow supply available for the hydropneumatic pump is not high enough
in pressure to drive the PDVV for the maximum oil pressure range needed.
• The high flow supply available for the hydropneumatic pump is low quality
shop or factory air that cannot be cleaned well enough to be used to supply
the PDVV and associated control valves.
• The drive air pressure needed for the PDVV, if accidentally supplied to the
hydropneumatic pump, could accidentally cause an overpressure situation
that would be hazardous to the system connected to the OPG1.
OPG1 is delivered set up for two independent pneumatic power connections.
This is the recommended configuration
Generally, when one drive air supply is used, it is “shop” or “plant” air with
relatively high volume flow that is adequate to supply both the
hydropneumatic pump and the PDVV.
When two supplies are used, non-lubricated “shop” or “plant” air with
relatively high volume flow supplies the hydropneumatic pump and a separate
supply of regulated, clean, dry compressed air or nitrogen from a bottle
supplies the PDVV.
Making Two Independent Pneumatic Power Connections
The OPG1, as delivered, is configured for two independent pneumatic
power connections. Make the connections following
PDVV DRIVE Pneumatic
Power Connection (Left Side) Requirements and DRIVE Pneumatic Power
Connection (Right Side) Requirements below. Both connections are
1/4 in. NPTF. Use Teflon™ tape or an other thread sealant to minimize leakage.
PDVV DRIVE Pneumatic Power Connection (Left Side) Requirements
When the PDVV DRIVE port is used to provide an independent pressure supply
to the PDVV, since the flow requirements are very low, the supply is usually
regulated Nitrogen or instrument grade air from a compressed air bottle.
• Pressure: 550 to 900 kPa (80 to 130 psi), regulated ± 20 kPa (3 psi)
• Must be regulated
• Flow: 200 sccm (< 0.01 scfm)
• NOT lubricated
• Instrument grade N
or air or high quality shop air with filter/dryer installed
2
upstream (0 °C dew point, 10 micron filter)
OPG1 must be supplied with NON-LUBRICATED drive air. The internal
components are permanently lubricated. The oil in lubricated air can
contaminate the small diameter tubing inside OPG1 and lead to erratic
behavior requiring difficult and costly cleaning.
DRIVE Pneumatic Power Connection (Right Side) Requirements
• Pressure: 550 to 830 kPa (80 to 120 psi), regulated ± 30 kPa (5 psi)
• Flow: 50 slm (1.8 scfm) minimum
• NOT lubricated
• Shop air with filter/dryer installed upstream (0 °C dew point, 10 micron filter)
The maximum output pressure of the hydropneumatic pump is the drive air
pressure x 400.
Making a Single Pneumatic Power Connection
This configuration is optional and requires reconfiguring the OPG1 internal
pneumatic connections (see
Connection). OPG1 is delivered set up for two independent pneumatic power
connections as descr ibed in Section 2.3.1.2,
Pneumatic Power Connections.
Once the OPG1 is properly configured for a single pneumatic power connection,
connect the pneumatic pressure source to the 1/4 in. NPT F connection labeled
DRIVE on the right side of the OPG1 housing. Use Teflon™ tape or another
thread sealant to minimize leakage.
When using the single DRIVE port to supply drive air to both the
hydropneumatic pump and the PDVV, there is no regulator for the PDVV drive
pressure in the OPG1. Therefore, the source connected to the DRIVE port
must be regulated appropriately to supply the PDVV (see Table 2).
OPG1™ OPERATION AND MAINTENANCE MANUAL
Single pneumatic power connection air requirements (see Table 2):
• Pressure: 550 to 900 kPa (80 to 130 psi) regulated ± 20 kPa (3 psi)
• Flow: 50 slm (1.8 scfm) minimum
• NOT lubricated
• Filter/dryer installed upstream
OPG1 must be supplied with NON-LUBRICATED drive air. The internal
components are permanently lubricated. The oil in lubricated air can
contaminate the small diameter tubing inside OPG1 and lead to erratic
behavior requiring difficult and costly cleaning.
Reconfiguring OPG1 for a Single Pneumatic Power Connection
Reconfigure OPG1 pneumatic connections using the following procedure:
Close the OPG1 tank cover fully and plug all hydraulic TEST ports.
Place the OPG1 back down on the bench, so that the front panel is straight
up and the open bottom is towards you. Make sure that there is enough oil
in the tank so that the pump draw port remains covered. Fill to just under oil
return tube (see Section 4.2).
Remove cap (5) from DRIVE port tee (7) and set aside.
Disconnect PFA PDVV supply tube (6) from the PDVV DRIVE port filter
connection (4) and reconnect it to the DRIVE port tee (7).
Install cap (5) onto the PDVV Drive port filter connection (4).
Connect recommended pressure to DRIVE port (11) (see Section 2.3.1.2,
Making Single Pneumatic Power Connection). Check all new connections
for leaks using a liquid leak detector. Correct leaks if present.
Connecting to a DHI RPM3 or PG7302 Using Standard OPG1
Interconnection Accessories
OPG1 is delivered with a fittings accessory kit (see Section 2.1.2, Table 1). This kit
includes the high pressure hardware necessary to connect OPG1 to a DHI RPM3
or PG7302 and operate at pressure up to 200 MPa (30 000 psi). See Figure 5
for the recommended layout and to identify the parts used from the
interconnection kit. These setups assume that the TEST port at the top of the
OPG1 oil tank or an open leg of the tee will be used to connect the DUT. To adapt
to the top test port connection, install one of the DH500 F x 1/8 in. NPT M or
DH500 F x 1/4 in. NPT F adaptors onto one of the 2.75 in. DH500 nipples and
install the nipple into the DH500 F of the top test port.
1. OPG1 5b. 5 in. (127 mm) DH500 1/8 in.
2a. 12 in. (305 mm) DH500 Nipple Tube Weld Nipple (slightly flexible)
2b. 6 in. (152 mm) DH500 Nipple 6a. PG7302
3. DH500 Tee 6b. RPM3
4. DH500 Plug 7. PG Terminal
5a. 2.75 in. (70 mm) DH 500 Nipple 8. TEST Port
Figure 5. Connecting OPG1 to PG7302 or RPM3
Other Hydraulic Pressure Interconnections
OPG1 is delivered with a fittings accessory kit (see Section 2.1.2, Table 1). This kit
is designed to provide a standard connection to a DHI OPG1 or PG7302. It is
configured of standard DH500 fittings and tubing and can be adapted for a
variety of connections to operate up to 200 MPa (30 000 psi).
The welded 1/8 in. tube can be very useful when a small amount of flexibility is
needed to make a connection. Take care not to kink the tube.
The DH500 x 1/4 in. NPT F and DH500 x 1/8 in. NPT M can be used to convert a
DH500 tube to standard NPT connections.
Always use external tubing and fittings rated for pressure equal to or
greater than the maximum pressure the OPG1 will be used to generate.
When planning system interconnections, consider that the time required to
generate and stabilize a pressure is a direct function of the test volume and
the mechanical stability of the test tubing and vessels. Always minimize volume
to the extent possible and use thick walled, high pressure tubing and vessels.
When planning a DUT or other fitting make and break point external to OPG1,
consider that if the point is lower than the OPG1 oil tank, oil will run out of
the tank through the open point when OPG1’s OUTLET valve is open.
The fluid head reference level of OPG1 when vented (OUTLET valve open), is
the top of the tank’s oil return overflow tube (see Section 3.2.6).
2. INSTALLATION
2.4 POWER UP AND VERIFICATION
2.4.1 APPLY PNEUMATIC POWER (DRIVE AIR)
Proceed as follows (numerical references refer to Section 3.2, Figure 8):
n Fully back off the DRIVE SET regulator (4).
o Close the TEST INLET valve (5).
p Open the TEST OUTLET valve (8).
q Connect the drive air pressure to the DRIVE Port (and PDVV DRIVE Port, if used)
(see Section 2.3.1.2). The connections are 1/4 in. NPT F.
r Adjust the external drive air regulator(s) to apply the appropriate level of pressure to the
DRIVE Port (and PDVV DRIVE Port, if used) (see Section 2.3.1.2, Table 2).
2.4.2 ADJUST HYDROPNEUMATIC PUMP DRIVE AIR
PRESSURE
This section assumes that the OPG1 system has already been set up, including pressure
interconnection (see Section 2.3).
OPG1 hydraulic output pressure is directly proportional to pump DRIVE pressure. When
the OPG1 INLET valve is opened, the full pump pressure may be applied to the test system
very rapidly. ALWAYS adjust the pump pneumatic drive pressure low enough so that the
maximum pump output does not exceed the maximum pressure rating of the devices to
which OPG1 is connected.
Turn the DRIVE SET Regulator CW and observe the PUMP DRIVE Gauge to set the drive
air pressure to the desired level (the BLUE indication on outside of gauge gives approximate
oil pressure that will be generated).
2.4.3 CHECK PROPER OPERATION OF HYDROPNEUMATIC
PUMP AND LEAK CHECK
Checking the proper operation of the hydropneumatic pump and leak checking has two steps.
The first step is purging air from the pump hydraulic circuit. The second step is generating
high pressures.
2.4.3.1 STEP ONE: PURGING AIR FROM THE HYDRAULIC
PUMP CIRCUIT
Proceed as follows (numerical references refer to Section 3.1, Figure 7):
n Verify that there is oil in the tank and verify that all test connections are
plugged or dead ended.
o Open the OUTLET valve (8) fully.
p Open the INLET valve (9) fully.
q If drive pressure has been properly connected and set, pump should begin cycling.
r Observe tank oil return overflow tube (5). Continue allowing pump to cycle
until bubble free oil flows regularly from the tube. If no oil appears, or
bubbles continue to appear, the internal purging procedure must be used
(see Section 2.4.3.3).
If hydropneumatic pump is filled with air (cavitated), closing inlet valve
will not stop pump from operating. To stop pump, turn AIR DRIVE
regulator (1) fully CCW to stop air flow.
s After a successful purge, close the INLET valve (8), then the OUTLET valve
(9) and proceed to STEP TWO (see Section 2.4.3.2) of hydropneumatic
pump operation checkout.
2.4.3.2 STEP TWO: GENERATING A PRESSURE
Before applying pressure to the OPG1 and/or the system connected to it, be
sure that all pressure vessels and connections are rated for the pressure
levels that will be applied and that all connections have been properly
tightened (see Section 2.4.4).
OPG1 hydraulic output pressure is directly proportional to pump DRIVE
pressure. When the OPG1 INLET valve is opened, the full pump pressure may
be applied to the test system very rapidly. ALWAYS adjust pump drive air
pressure low enough so that the maximum pump output does not exceed the
maximum pressure rating of the devices to which OPG1 is connected (see
Sections 2.4.2 and 3.2.1).
Proceed as follows (numerical references refer to Section 3.1, Figure 7):
n Verify that there is oil in the tank.
o Connect a high pressure indicating device to one of the OPG1 TEST ports (4, 6,
7). Plug all other TEST ports (4, 6, 7).
There are three TEST ports: One on each lower, rear side and one on the
top in the middle of the tank.
p Fully close the OUTLET valve (8).
q Slowly open INLET valve (9).
r The pump should begin to cycle and the pressure indicated on the high
pressure device should increase. If the pump does not cycle, the drive
pressure is set too low or the pump is not operating correctly. If the
pump cycles but the pressure does not increase:
• the pump is not properly primed (see Section 2.4.3.1);
• there is a leak in the system to which OPG1 is connected or in the
OPG1 itself;
2. INSTALLATION
• air flow to the pump is too low; or
• the pump is not operating properly.
s Keep INLET valve (9) open until desired oil pressure is set.
t Fully close INLET valve (9).
u Leak Check: The pressure indicated by the high pressure device connected
to the TEST port should stabilize and hold. If it does not, there is a leak
in the system to which OPG1 is connected or in OPG1 itself.
The time required for pressure to stabilize after the pressure has
been changed is directly proportional to the volume connected to
OPG1 and the mechanical stability of the volume's connections and
vessels. To reduce stabilization time, go beyond the pressure set
point and return.
v When leak checking is complete, slowly open the OUTLET valve (8) to
remove pressure and vent to atmosphere.
2.4.3.3 PRIMING THE HYDROPNEUMATIC PUMP BY SYRINGE
INJECTION
The hydropneumatic pump injection priming procedure is only required if the
regular purge procedure fails (see Section 2.4.3.1).
Numerical references in this section refer to Section 4.2, Figure 11.
To prime the pump with the syringe proceed as follows:
n Back off the OPG1 DRIVE SET regulator to zero by turning it fully CCW.
o Open INLET valve and OUTLET valve.
p Remove oil tank cover (2).
q Install 2-104 O-ring on tip of 10 cc syringe (both supplied in OPG1
accessory kit, see Section 2.1.2).
r Fill syringe with oil from the tank.
s Insert the tip of the syringe into the tank pump draw port (4) and press so
that the O-ring seals against bottom of tank.
t Increase pump drive air pressure by rotating DRIVE SET regulator CW until
the pump begins to cycle. When pump begins to cycle, press syringe
plunger, injecting oil into pump. Continue until oil returning through the tank
oil return overflow tube (3) is free of air bubbles. Note that in some cases, air
free oil will return before trapped gas is expelled from the pump.
2.4.3.4 INTERNAL PURGE OF HYDROPNEUMATIC PUMP
The hydropneumatic pump internal purge procedure is only required if the
regular purge procedure fails (see Section 2.4.3.1) and a syringe is not available
to perform the injection priming procedure.
To purge the hydropneumatic pump internally, proceed as follows (see Figure 6):
n Verify that there is oil in the tank.
o Back off DRIVE SET regulator to zero.
p Position the OPG1 so that you can access the hydraulic output pressure
connection (1) of the hydropneumatic pump while keeping the OPG1 in its
normal, horizontal operating position. This is accomplished by placing either
end on separate tables and accessing the pump from beneath OPG1 or by
slightly lifting the front of the OPG1.
q Open the INLET valve fully.
r Use a wrench to turn the hydraulic output pressure connection gland (1)
1/8 turn CCW. This cracks the connection so that output oil from the pump
can escape through the safety weep hole.
s Slightly adjust DRIVE SET regulator CW until the pump starts cycling.
Figure 6. Hydropneumatic Pump
t Allow the pump to cycle until clear, bubble free oil flows regularly from the
weep hole. If this does not occur, the pump may require service. Contact
your DHI Authorized Service Provider (see Section 6.2).
u Retighten the hydraulic output pressure connection (1) by turning the gland
nut approximately 1/8 turn CW.
v Go to Section 2.4.3.2 and proceed with the normal purge procedure.
2.4.4 PRECAUTIONS TO TAKE BEFORE GENERATING
PRESSURE/SAFETY CONSIDERATIONS
Before using the OPG1 to generate and adjust pressure, consider the following:
• Check that all connections, vessels and DUTs connected to OPG1 are rated for the
pressure to be generated and that all fittings are properly tightened.
• Opening the INLET valve opens to the output of the hydropneumatic pump. As long as the
INLET valve is open, the hydropneumatic pump will pump until it stalls. To avoid accidental overpressure of the items to which OPG1 is connected, always adjust the DRIVE SET
regulator so that the hydropneumatic pump output will be lower than the maximum desired pressure BEFORE opening the INLET valve (see Sections 2.4.2 and 4.2.1).
Always adjust the DRIVE SET regulator so that the hydropneumatic pump output is
not higher than the maximum desired pressure BEFORE opening the INLET valve.
Failure to adjust the DRIVE SET regulator increases the chances of accidental
overpressure of the system connected to OPG1.
• The
• Check oil tank level before operating and regularly during operation. Operating with an
and push button valves can increase pressure very quickly. Observe pressure
evolution carefully when operating these valves (see Section 3.2.3).
empty oil tank will cause the hydropneumatic pump to draw air and require priming it (see
Section 2.4.3).
2. INSTALLATION
• Put the PDVV in the START position when starting a calibration or test sequence
(see Section 3.2.3).
• Systems and DUTs connected to OPG1 should be purged of air before they are
pressurized (see Section 3.2.5).
•If there is an open point in the system to which OPG1 is connected that is lower than the
OPG1 tank, oil will run out of the OPG1 tank through this point when the OUTLET valve
is open. Close the OUTLET valve when a point lower than the tank is open.
•The fluid head reference level of OPG1 when the OUTLET valve is open is the top of the
tank return overflow tube. Consider the difference between this reference level and the
reference measuring device reference level to avoid zero gauge points that are
inconsistent with other pressure points (see Section 3.2.6).
2.5 SHORT TERM SHUT-DOWN
When leaving OPG1 at rest but still set up for operation:
n Fully close the INLET valve.
o Release hydraulic pressure by fully opening the OUTLET valve.
p Plug any open point in the hydraulic test system connected to OPG1 that is lower than the OPG1
tank or the oil will run out of the tank through the open point.
q Release pump drive pressure by fully backing off the DRIVE SETregulator.
2.6 LONG TERM STORAGE AND SHIPPING
To prepare OPG1 for long term storage or shipping:
n Release hydraulic pressure by fully opening the OUTLET valve.
o Release pump drive pressure by fully backing off DRIVE SETregulator.
p Release pneumatic drive pressure and disconnect the DRIVE and PDVV DRIVE pressure connection(s).
Cap both ports with plastic caps if available.
q Close the OUTLET valve and INLET valve.
r Disconnect all hydraulic pressure connections and plug the connections using DH500 plugs held by
gland nuts (DH500 plugs were delivered with OPG1). There are three hydraulic connections: one on
either side labeled TEST and one on top at the center of the tank cover.
s Screw the tank cover firmly shut. Oil may be left in the tank.
When shipping OPG1, use the original shipping materials, if possible. When using alternate materials
(If the original shipping materials are not available) take care to assure that: a) the front panel
controls and indicators are protected; b) the top mounted oil reservoir is not subjected to shock or
load; c) the tubing and components exposed through OPG1’s open bottom are protected. OPG1 must
ride on its four feet - NOT on the internal components.
Numerical references in this section refer to Section 3.1, Figure 7.
OPG1 is a self-contained system designed to generate and adjust pressure from atmosphere
(zero gauge) to 200 MPa (30 000 psi) into static pressure test and calibration systems. OPG1 combines
the capability to fill a system with oil and execute large pressure changes very rapidly with very fine
pressure adjustment around a point.
OPG1 uses two different techniques to generate and adjust pressure.
The first means of generating and adjusting pressure is the hydropneumatic pump (2) combined with
the oil tank (3), DRIVE SET regulator (1), INLET valve (9) and OUTLET valve (8). This combination is used for filling the system under test, large pressure changes and rough pressure control.
The valves are Belleville spring loaded, highly progressive, half-turn needle valves. The pump is a
pneumatically powered, gate valve controlled, piston pump similar to a double-acting pneumatic cylinder.
There is a ratio of 400:1 between the pneumatic piston and hydraulic plunger. The pump will operate
continuously until the pneumatic drive pressure on the pneumatic piston is in equilibrium with the oil
pressure on the oil plunger. For example, if the pneumatic drive pressure is 500 kPa (75 psi), the pump
will cycle until the oil pressure reaches 200 MPa (30 000 psi). The pump draws oil from the oil tank on
top of OPG1. The DRIVE SETregulator (1) is used to set the pneumatic drive pressure and thus the oil
output pressure. The pump oil output is connected to the INLET valve (9). Opening the INLET valve
connects the pump output to the test system causing the pump (2) to cycle, drawing oil from the tank as
needed and pressurizing the system. Opening the OUTLET valve (8) returns oil to the tank (3),
depressurizing the system.
The second means of generating and adjusting pressure is the Pneumatically Driven Variable
Volume (PDVV) (10) combined with the PDVV (+) valves (12) and PDVV (-) valves (11).
This combination is used for smaller pressure changes and fine pressure control. The PDVV is a
pneumatically actuated variable volume. A piston or plunger in a cylinder is exposed to the oil pressure.
The other end of the plunger is connected to a dome loaded pneumatic actuator. Changing the
pneumatic pressure on the dome loaded actuator causes the plunger to move, increasing or decreasing
oil pressure. A spring returns the plunger to its minimum stroke position when there is no pressure on it.
A mechanical system tracks movement of the plunger and an indicator (17) displays the plunger position
on the front panel. The PDVV (+) valves (12) and PDVV (-) valves (11) are momentary, poppet valves
that open when pressed. The (+) valves (12) admit drive air pressure to the PDVV actuator causing the
PDVV piston to move forward compressing the oil and increasing the pressure. The (-) valves (11) have
the opposite effect causing pressure to decrease.
All OPG1 operational functions are accessed from the instrument front panel. Sections 3.2.1 to 3.2.6
detail the various functions.
1. PDVV Drive Air/Test Oil Pressure Gauge
2. PDVV Piston Position Indicator
3. Pump Drive Air/Inlet Oil Pressure Gauge
4. Pump Drive Air Set Regulator
5. Test Inlet Valve Knob
6. PDVV Increase Fast and Slow Buttons
7. PDVV Decrease Fast and Slow Buttons
8. Test Outlet Valve Knob
Figure 8. Front Panel
3.2.1 SETTING INLET PRESSURE, DRIVE SET REGULATOR ADJUSTMENT
Numerical references in this section refer to Section 3.2, Figure 8.
The DRIVE SET regulator (4) is a self venting regulator that sets the pneumatic drive
pressure to the hydropneumatic pump. This determines the oil pressure that the pump will
generate before stalling and that is available on demand when the INLET valve (5)
is opened.
The PUMP DRIVE gauge (3) indicates the pump drive pressure on its inner dial and the
corresponding pump output oil pressure on its outer dial (BLUE numbers). Use the outer
BLUE indication to predict the maximum pressure that will be generated when the inlet valve
is opened.
With the INLET valve (5) closed, use the DRIVE SET regulator (4) and the PUMP DRIVE gauge (3) indication to set the desired maximum pump output pressure. This is generally
done at the beginning of a test or calibration based on the maximum pressure of
the calibration. It is good practice to set the pump output pressure below the maximum
pressure desired to avoid accidental overpressure. The PDVV can then be used for the final
pressure adjustment at the maximum pressure (see Section 3.2.3).
The DRIVE SET regulator sets the oil pressure output of the hydropneumatic pump.
When the INLET valve is opened, this pressure can be generated very rapidly in the
system connected to OPG1. Use caution in setting the pump drive pressure and always
check the setting and adjust if necessary before using the INLET valve (see Sections 2.4.2 and 3.2.1).
3.2.2 ROUGH PRESSURE GENERATION/CONTROL, INLET
AND OUTLET VALVE OPERATION
Numerical references in this section refer to Section 3.2, Figure 8.
The INLET valve (5) and OUTLET valve (8) are high pressure needle valves.
Their operation is highly progressive over a half-turn with mechanical stops at each end so
they cannot be overtightened. The valve is turned CW to close and CCW to open. A WHITE dot
on the handle body indicates its current open/close position.
The INLET valve (5) controls the flow of oil from the hydropneumatic pump into the
test system. When it is closed, the pump is shut off from the test system and dead ended.
When the INLET valve is open, the pump output is connected to the test system and can fill
and generate pressure into the system.
The OUTLET valve (8) controls the flow of oil from the test system back to the tank. When it
is closed, the test system is shut off from the tank. When the OUTLET valve is open, the
system returns oil to the tank and is opened to atmospheric pressure.
The INLET valve (5) and OUTLET valve (8) are used to execute large pressure changes in
the test system and for rough pressure control. The INLET valve is used to connect to the
pump to purge and prime the test system at the beginning of a test or calibration.
The OUTLET valve, when fully opened, is the means of opening the test to atmosphere and
setting zero pressure. The INLET valve and OUTLET valve are not generally used for
ON/OFF action but progressively to roughly set the desired pressure. Exercise caution when
operating the valves to not open them too quickly which could cause pressure in the system
to change much more rapidly than desired.
The INLET valve connects the output of the hydropneumatic pump to the test system.
When the INLET valve is opened, high pressure can be generated very rapidly in the system
connected to OPG1. Use caution in opening the INLET valve and always check the PUMP
DRIVE gauge before doing so (see Sections 2.4.1 and 3.2.1).
3.2.3 FINE PRESSURE ADJUSTMENT, PDVV (+) AND (-) VALVE
OPERATION
Numerical references in this section refer to Section 3.2, Figure 8 except where
specified otherwise.
The PDVV (+) valves (6) and PDVV (-) valves (7) are push button, poppet valves that control
the supply and exhaust of drive air pressure to the PDVV actuator (see Section 3.1).
When the push button is pressed, the valve opens. When the push button is released the
valve closes.
The valves labeled
to back off and pressure to decrease. The valves labeled
actuator causing the PDVV plunger to move forward and pressure to increase. The
valves are for high speed PDVV operation. The
operation.
The PDVV (+) valves (6) and PDVV (-) valves (7) are to make small pressure changes and
for fine pressure control. Brief momentary action on the
jog pressure in very small amounts around a pressure point.
and release gas from the PDVV actuator causing the PDVV plunger
are admit gas to the PDVV
and
and valves are for slow speed PDVV
and valves is used to bump or
The actual rate of pressure change caused by the PDVV (+) valves and PDVV (-) valves is
dependent on the test volume that is connected to OPG1. Increasing the test volume lowers
the rates and pressure step size. The maximum pressure that can be generated by the
PDVV (+) valves is dependent on the drive air supply (see Section 2.3.1.2, Table 2).
The position of the PDVV plunger is indicated
by the PDVV POSITION indicator (2).
The RED index (Figure 9, Ref 4) on the
START
indicator tracks the movement of the
PDVV plunger. Minimum and maximum end
of stroke positions (Figure 9, Refs 3 and 1) as
well as a recommended start position
(Figure 9, Ref 2) are indicated. The full stroke
displacement of the PDVV plunger from
maximum to minimum end of stroke is 1 cc
(0.06 in.
3
).
1.
PDVV Plunger Maximum End of Stroke
2.
PDVV Plunger Recommended Start Position
3.
PDVV Plunger Minimum End of Stroke
4.
PDVV Plunger Current Position (red/white line)
Figure 9. PDVV Position Indicator
PDVV
POSITION
The current air drive pressure on the PDVV actuator and approximate corresponding oil test
pressure are indicated by the PDVV DRIVE gauge (1). The oil test pressure indication is highly
approximate and only valid when the PDVV plunger is NOT at an end of stroke position.
For the PDVV (+) valves (6) and PDVV (-) valves (7) to have an effect, the PDVV plunger
must have stroke available. If the PDVV is at its end of stroke (Figure 9, 1. and 3.), the
plunger cannot move to change pressure. The recommended PDVV START position
(Figure 9, 2.) puts the plunger at the middle of its stroke so 50 % of PDVV displacement is
available in either direction. The PDVV plunger can be positioned without affecting oil
pressure using the
and valves when the OUTLET valve is open (oil pressure vented).
The plunger is returned to minimum end of stroke position by a spring. The PDVV plunger is
usually set to the desired position at the start of a calibration or test.
If the PDVV plunger reaches end of stroke during a calibration or test, used the INLET valve
and/or OUTLET valve to increase or decrease the pressure, as needed.
The PDVV (+) valves (6), generate pressure indefinitely when opened. Use caution
when using these valves not to generate more pressure than desired.
3.2.4 CONNECTING A DEVICE UNDER TEST (DUT)
The device to be tested or calibrated should be connected either to a TEST port configured
on the interconnections external to OPG1 or to the OPG1 TEST port on the top of the unit at
the center of the tank (see Section 3.1, Figure 7). The test connection is a DH500 F (DH500
is a gland and collar type fitting for 1/4 in. (6.35 mm) coned and left hand threaded tube.
DH500 is equivalent to AE F250C, HIP HF4, etc.).
The DH500 test connection can be converted to 1/8 in. NPT M or 1/4 in. NPT M using the
2.75 in. (7 mm) tube and DH500 F X 1/8 in. NPT M or DH500 F x 1/4 in. NPT M adaptor
supplied in the OPG1 accessories. Install the tube into the adaptor.
OPG1 covers a very wide range of pressures all the way up to 200 MPa (30 000 psi). It is
the user’s responsibility to assure that fittings and devices connected to OPG1 are rated
for the pressures at which they will be used.
If the DUT connection is lower than the OPG1 oil tank, when the OUTLET valve is open and
the DUT connection is open, oil will run out of the tank through the DUT connection.
Air is highly compressible. Oil is not. To the extent possible, air should be purged from the
system and devices that are connected to OPG1 prior to applying pressure to them.
Leaving air in the DUT reduces OPG1 efficiency, increases the time required to generate
pressures, increases the dangers associated with high pressure operation and makes it more
difficult to set a valid zero point.
The system and/or DUTs that are connected to OPG1 can be filled with oil prior to connecting
them or they can be purged using OPG1. To purge air using OPG1, open the system or DUT
at the highest point possible. Close the OPG1 OUTLET valve. Then carefully open the
INLET valve causing oil to be drawn from the tank and pumped into the system. Observe
the oil level at the purge point. Close the INLET valve when oil is present at the purge point.
While purging, watch the tank oil level carefully and keep filled.
3.2.6 MEASUREMENT REFERENCE LEVEL WHEN VENTED
Generally, the test or calibration system is opened to atmosphere (zero gauge pressure) by
opening the OPG1 OUTLET valve.
The fluid head reference level when the OUTLET valve is open is the top of the tank return
overflow tube. This point is 258 mm (10.15 in.) above the surface on which OPG1 is sitting
(see Figure 10).
Figure 10. Fluid Head Level When Vented, INLET Valve Open
When the OUTLET valve is closed, the fluid head reference level is at the device being used
as the measurement reference. Consider the possible difference in fluid head between the
two conditions or incorrect fluids head corrections will be applied and the zero point will be
inconsistent with other measurements.
OPG1 is designed so that the top of the oil tank return overflow tube aligns with the
measurement reference level of a PG7302 oil operated piston gauge. This assures that,
when using a PG7302 piston gauge, the nominal reference level is the same at zero with
the OPG1 vented and when pressures are defined by the piston gauge.
When the OPG1 OUTLET valve is open, the test system is connected to the OPG1 oil tank.
If there is an open point in the test system below the oil level in the oil tank, oil will run
from the tank and out of the open point in the test system.
3.3 TYPICAL OPERATING SEQUENCE FOR A COMPLETE
CALIBRATION OR TEST
OPG1 is most often used to generate and adjust pressures to a reference measuring device and a DUT
when performing a test or calibration. The reference measuring device may be a pressure monitor such
as a digital indicator or gauge or a piston gauge or deadweight tester. The typical operational sequence
is as follows (numerical references refer to Section 3.2, Figure 8):
n Connect the DUT to the OPG1 TEST port or to a test port on the external system to which OPG1 is
connected.
o Purge the DUT: If it is not already closed, close the OUTLET valve (8). Open the DUT at the
highest point possible. Carefully open the INLET valve (5) and observe the purge point in the test
system until oil is present there. Close the INLET valve.
p Position the PDVV plunger: Open the OUTLET valve (8). Use the PDVV (+) valves (6) and PDVV
(-) valves (7) and the PDVV POSITION indicator (2) to position the PDVV plunger at the START
position or at another desired position (for example near the minimum end of stroke if the PDVV is to
be used extensively for pressure generation).
q Set the pump drive pressure: Adjust the DRIVE SET regulator (4) and observe the pressure on
the PUMP DRIVE gauge (3). Set the pressure so that the pump oil pressure output will be just under
the maximum pressure to be reached in the test.
r Take the starting zero reading on the DUT: With the OUTLET valve (8) open, the pressure in the
test system is zero gauge and the fluid head reference level is the top of the oil tank return overflow tube.
s Set ascending test pressures: Carefully open the INLET valve (5) and control the oil input from the
pump to set the pressure in the test system just under the desired test point. Then use the PDVV (+) valves (6) and PDVV (-) valves (7) to adjust the pressure to the exact test pressure desired or, if the
reference is a piston gauge, to float the piston gauge piston. Repeat this process for all of the
ascending increments. If the increments are small enough for the PDVV displacement to generate
the pressure, only the PDVV (+) valves may be needed to generate the next pressure. If the PDVV
runs out of stroke, use the INLET valve to generate pressure.
t Set descending test pressures: Very carefully open the OUTLET valve (8) and control the oil
return to the tank to set the pressure in the test system just over the desired test point. Then use the
PDVV (+) valves (6) and PDVV (-) valves (7) to adjust the pressure to the exact test pressure
desired or, if the reference is a piston gauge, to float the piston gauge piston. Repeat this process for
all of the descending increments. If the increments are small enough for the PDVV displacement to
generate the pressure, only the PDVV (-) valves may be needed to generate the next pressure. If
the PDVV runs out of stroke, use the OUTLET valve to reduce pressure.
u Vent the system and disconnect the DUT: Open the OUTLET valve (8)fully. Disconnect
the DUT. If the test port is lower than the oil level in the oil tank, be sure to close the OUTLET valve
so that oil does not run out of the tank through the test port.
OPG1 was designed for maintenance free operation. The hydropneumatic pump and PDVV are
permanently lubricated. No maintenance is required other than:
•Maintain oil level in tank: Replace lost oil to never allow the tank to empty which would cause the
pump to run without oil (see Section 4.2).
•Replace oil and purge hydraulic system when oil becomes dirty: Over time, contamination from
the system to which OPG1 is connected may cause the oil to become contaminated. It should then
be replaced and the OPG1 hydraulic system may be purged (see Section 4.3).
•Clean/replace filter elements on PDVV and hydropneumatic pump drive air filters: The filters
may become contaminated and restrict the free flow of drive air pressure. They should then be
cleaned or replaced (see Section 4.4).
Maintenance and repair services for OPG1 are offered by authorized DHI Authorized Service Providers
(see Section 6.2, Table 4).
OPG1 is a sophisticated pressure generation and adjusting instrument with advanced features
and functions. Before assuming that unexpected behavior is caused by a system defect or breakdown,
use this manual and other training facilities to become thoroughly familiar with OPG1 operation.
For rapid troubleshooting assistance in specific situations, see Section 5.1.
OPG1 is covered by a limited one year warranty (see Section 6.2). Unauthorized service or repair
during the warranty period is undertaken at the owner's risk and may cause damage that is NOT
covered under product warranty and/or may void the product warranty.
4.2 FILLING THE TANK
The oil level in the OPG1 tank should be maintained at all times. Opening the INLET valve and operating the
hydropneumatic pump when the tank is empty will cause the pump to draw air and lose its prime.
To fill the oil tank, proceed as follows (numerical references refer to Figure 11):
n Unscrew the tank cover/oil fill funnel (2) until a gap for oil passage can be seen between the
TEST port shaft (1) and the cover.
o Using the tank cover as a funnel, pour oil into the tank to just under the top of the overflow
tube (3). DO NOT bring the oil level in the tank above the top of the overflow tube.
p Leave the tank cover open to allow oil to drain from the cover into the tank when swapping DUTs
and to allow air to escape from the tank when venting oil back into the tank.
If OPG1 is used to generate and adjust pressure into test systems and DUTs that are not clean, the oil
returned to OPG1 will be contaminated.
Observe the oil in the OPG1 tank. If its color is significantly different from the color of clean oil or if any
particulate contamination can be observed, replace the oil in the oil tank and purge the OPG1 oil system.
To replace the oil in the oil tank, proceed as follows:
n Fully remove the oil tank cover by unscrewing it (rotating CCW) and removing it completely.
o Remove the oil from the tank with a suction bulb or similar device.
p Clean out the tank with paper towels or rags. Remove all particulates that may be present.
q Refill the tank with fresh oil to just under the overflow tube.
To purge OPG1 of dirty oil, proceed as follows:
n Fill the oil tank with clean oil (see Section 4.2).
o Open one of the side TEST ports and put a cup under the port.
p Close the OUTLET valve. Open the INLET valve causing the pump to cycle and oil to be drawn
from the tank and expelled from the open TEST port. Observe the oil coming out of the test port until
it runs clean. TAKE CARE to not allow the oil level in the tank to run out or the pump will draw air
and lose its prime, requiring it to be reprimed (see Section 2.4.3). When the oil coming out the TEST
port is running clean, close the INLET valve.
q Repeat from Step n, if necessary, until the oil running out the TEST port runs clean and the oil in the
tank is clean.
4.4 CLEANING/REPLACING DRIVE AIR FILTER ELEMENTS
There are filters on the OPG1 drive air inlet ports, one on the PDVV DRIVE port and the other on the
DRIVE port. If the drive air supplied is excessively dirty, these filters may become contaminated and
restrict air flow to the PDVV and/or hydropneumatic pump (see Section 3.1, Figure 7).
The drive air filters are filter bodies with scintered elements. To clean or replace the drive air filters the
filter body must be removed from OPG1.
To remove and reinstall the drive air filters, proceed as follows:
n Close the OPG1 tank cover fully and plug all hydraulic ports. Ensure that tank is filled to just under oil
return tube.
o Place the OPG1 back down on the bench, so that the front panel is up with the open bottom towards
you.
p Disconnect the filter connection fittings (2, 4) for the PDVV DRIVE filter (3) and (8, 10) for DRIVE filter (9).
Remove the filter (3) and/or (9).
q To reinstall the filter, make the filter connections (2) and (4) or (8) and (10). Take care to ensure that
the filter is oriented in the correct direction (determined by the arrow on the filter body). The two
filters are identical.
r Connect recommended pressures (see Section 2.3.1.2, Table 2) to the PDVV DRIVE port and DRIVE
port. Check new connections for leaks using a liquid leak detector. Correct leaks, if present.
The filters may be replaced completely, cleaned by back flushing or disassembled and the filter element
cleaned or replaced.
To disassemble the filter body, open the body by unscrewing the filter body cap CCW. Once the filter
body cap is removed, the scintered filter element can be removed.
TWO INDEPENDENT PNEUMATIC POWER CONNECTIONS
(AS DELIVERED)
1. PDVV DRIVE Port (use optional) 5. Cap 9. DRIVE Filter
OPG1 is a sophisticated pressure generating and adjusting instrument with advanced features
and functions. Before assuming that unexpected behavior is caused by a system defect or breakdown,
the operator should use this manual and other training facilities to become thoroughly familiar with OPG1
operation. This troubleshooting guide is intended as an aid in identifying the cause of unexpected OPG1
behavior and determining whether the behavior is due to normal operation or an internal or external
problem.
Identify the symptom or unexpected behavior you are observing from the SYMPTOMS listed in Table 3.
A PROBABLE CAUSE is provided and a SOLUTION is proposed including references to manual
sections that provide information that may be of assistance.
Table 3. OPG1 Troubleshooting Checklist
SYMPTOM PROBABLE CAUSE SOLUTION
Test pressure continuously increases
even with all valves closed.
Test pressure continuously
decreases even with all valves
closed.
Test pressure takes too long to
stabilize or will never stabilize.
PDVV will not increase pressure. PDVV is at maximum end of stroke
PDVV will not decrease pressure. PDVV is at minimum end of stroke
Opening INLET valve does not
increase pressure.
Pump cycles continuously without
generating pressure.
Pump cycles continuously without
generating pressure.
Pump cycles continuously without
generating pressure.
Pump cycles excessively before
beginning to generate pressure.
Leak in INLET valve or leak in PDVV (+) valve(s).
Leak in OUTLET valve, leak in
PDVV (-) valve(s) or pneumatic
circuit, leak in OPG1 hydraulic circuit
or leak in test volume to which OPG1
is connected.
You are observing normal evolution
of pressure in an uncontrolled static
volume, excess gas in hydraulic
circuit.
position, PDVV supply pressure is
not high enough, or PDVV supply
plugged.
position.
Pump drive pressure too low. Adjust pump drive pressure, increase
The pump has lost its prime, oil tank
empty.
OUTLET valve is open. Close OUTLET valve (3.2.2).
There is a large leak in the test
system to which OPG1 is connected.
The test volume to which OPG1 is
connected has not been purged of air
and pump is filling test volume and
compressing air.
Isolate leak to INLET valve or PDVV (+) valve(s) by checking whether pressure
continues to increase when PDVV (-) valves
are opened or PDVV is at end of stoke.
Replace or repair valve(s) if qualified to do so.
Contact DHI Authorized Service Provider (7.2).
Identify and correct leak in test volume if
present. Isolate leak to OUTLET valve or PDVV (-) valve(s) by checking if pressure
continues to decrease when PDVV is in
minimum end of stroke position. Replace or
repair valve(s) if qualified to do so. Contact
DHI Authorized Service Provider (7.2).
Reduce test volume. Increase stability of test
tubing and vessels. Wait longer for stability.
Overshoot test point and return to reduce
stabilization time. Reduce reference reading
resolution to appropriate level.
Verify PDVV piston position and readjust if
necessary. Use INLET valve to increase
pressure. Increase pneumatic supply pressure.
Clean filter (3.2.3).
Verify PDVV piston position and readjust if
necessary. Use OUTLET valve to decrease
pressure (3.2.3).
pneumatic supply pressure if necessary (3.2.1,
2.3.1.2, Table 2).
Purge and prime pump (2.4.3).
Identify and correct leak in test system.
Purge air from test system before generating
pressure (3.2.5).
, Fast and slow , PDVV (+) valves. Used to increase pressure and for fine pressure
CW
CCW
Collar
DH500
DRIVE SET Regulator
DUT
Gland
Hydropneumatic Pump
INLET Valve
OUTLET Valve
PDVV (Pneumatically Driven
Variable Volume)
PDVV (+) Valves
PDVV (-) Valves
PDVV DRIVE Gauge
PUMP DRIVE Gauge
Test Pressure
Fast
and slow , PDVV (-) valves. Used to decrease pressure and for fine pressure
adjustment.
adjustment.
Clockwise
Counter-clockwise
The DH500 fitting element that is threaded onto the tube and provides a surface for the
gland to push against.
High pressure, gland and collar type fitting for 1/4 in. (6.35 mm) coned and left hand
threaded, stainless steel, tubes. DH500 is equivalent to AE F250C, HIP HF4, etc.
Self venting regulator used to regulate the drive air (pneumatic power) to the
hydropneumatic pump. Sets maximum inlet pressure.
Device or System Under Test. The device that is connected to OPG1 to be tested or
calibrated.
The “jam nut” in a DH500 fitting that pushes the collar on the tube into the seat.
Pneumatically operated, gate valve controlled, piston pump used to supply high pressure
oil to the INLET valve.
Progressive, half-turn, needle valve used to admit oil from the hydropneumatic pump into
the test system. Used to generate pressure and for rough pressure adjustment.
Progressive, half-turn, needle valve used to return oil from the test system to the oil tank.
Used to release pressure and for rough pressure adjustment.
A pneumatically actuated plunger in a cylinder used to increase and decrease the volume
of the oil test system and provide fine adjustment of the test pressure.
Momentary, push button actuated, poppet valves that admit air drive pressure to the PDVV
actuator causing the PDVV plunger to move forward, compressing oil and increasing the
test pressure. Used to increase pressure and for fine pressure adjustment.
Momentary, push button actuated, poppet valves that release air drive pressure from the
PDVV actuator causing the PDVV plunger to move back, decompressing oil and
decreasing the test pressure. Used to decrease pressure and for fine pressure
adjustment.
Analog gauge that indicates the PDVV actuator air pressure and the approximate
corresponding oil test pressure.
Analog gauge that indicates the pump drive air pressure and the approximate
corresponding pump oil output pressure.
The oil pressure in the OPG1 PDVV, at its TEST connections and in the system to which
the OPG1 is connected.
Except to the extent limited or otherwise provided herein, DH Instruments, a Fluke Company (DHI)
warrants for one year from purchase, each new product sold by it or one of its authorized distributors,
only against defects in workmanship and/or materials under normal service and use. Products which
have been changed or altered in any manner from their original design, or which are improperly or
defectively installed, serviced or used are not covered by this warranty.
DHI and any of its Authorized Service Providers’ obligations with respect to this warranty are limited to the
repair or replacement of defective products after their inspection and verification of such defects. All products to
be considered for repair or replacement are to be returned to DHI, or its Authorized Service Provider,
freight prepaid, after receiving authorization from DHI or its Authorized Service Provider. The buyer
assumes all liability vis-à-vis third parties in respect of its acts or omissions involving use of the products.
In no event shall DHI be liable to purchaser for any unforeseeable or indirect damage, it being expressly
stated that, for the purpose of this warranty, such indirect damage includes, but is not limited to, loss of
production, profits, revenue, or goodwill, even if DHI has been advised of the possibility thereof, and
regardless of whether such products are used individually or as components in other products.
Items returned to DHI under warranty claim but determined to not have a defect covered under warranty
or to not have a defect at all are subject to an evaluation and shipping charge as well as applicable repair
and/or calibration costs.
The provisions of this warranty and limitation may not be modified in any respect except in writing signed
by a duly authorized officer of DHI.
The above warranty and the obligations and liability of DHI and its authorized service providers exclude
any other warranties or liabilities of any kind.
Table 4. DHI Authorized Service Providers
DH INSTRUMENTS, A FLUKE COMPANY
WWW.DHINSTRUMENTS.COM
AUTHORIZED SERVICE PROVIDERS
COMPANY
DH Instruments, a Fluke
Company
Minerva Meettechniek B.V.
Nippon CalService, Inc.
DH Products Technical
Service Division
4765 East Beautiful Lane
Phoenix AZ 85044-5318
USA
Chrysantstraat 1
3812 WX Amersfoort
the NETHERLANDS
2-9-1 Sengen, Tsukuba-Shi
Ibaraki Prefecture 305
JAPAN
National Institute of Metrology
Heat Division
Pressure & Vacuum Lab
NO. 18, Bei San Huan Donglu
Beijing 100013
PR CHINA
ADDRESS
TELEPHONE,
FAX & EMAIL
Tel 602.431.9100
Fax 602.431.9559
cal.repair@dhinstruments.com
Tel (+31) 33.46.22.000
Fax (+31) 33.46.22.218
Tel 0298-55-8778
Fax 0298-55-8700
n-calservice@ohtegiken.co.jp
Tel 010-64291994 ext 5
Tel 010-64218637 ext 5
Fax 010-64218703
cxcen@mx.cei.gov.cn