Time Electronics 7195 Hydraulic Pressure Calibration Pump User Manual
- June 3, 2024
- Time Electronics
Table of Contents
Time Electronics 7195 Hydraulic Pressure Calibration Pump
Introduction
The 7195 benchtop pressure pump is a dual pressure source for hydraulic pressure applications. It is simple operation and achieves high pressure smoothly and easily. For media it uses oil or deionised water, and provides 85% vacuum and positive pressure 700bar (10,000psi). A high-quality screw press is designed for fine pressure adjustment, with adjusting resolution up to 0.001bar. For calibration applications the double output manifold provides finger-tight connections for a reference gauge and device under test. Further user features include the ergonomic handwheel for coarse pressure adjustment, fine adjust handles, release valve and isolating valve. The 7195 is comfortable and simple operation, with features that make it ideal for calibrating pressure transducers, gauges, and other pressure instruments. It is also ideal for use as a benchtop gauge comparator.
Specifications
- Media: Oil or deionised water
- Generated Pressure Range: 0.85bar vacuum to 700bar pressure (-12.5psi to 10,000psi pressure) Over Pressure: Up to 1000bar (15,000psi)
- Pressure Setting Resolution: 0.001bar (0.015psi)
- Material: Ram/adapters: 316 SS. Body: Steel/aluminum. Seals: Buna-N
- Pressure Connections: 2 x 1/4” BSP (1/4” NPT, M20 or other if specified)
- Height: 140mm
- Base: 290mm x 198mm
- Weight: 3.2kg (7.1 lbs)
- Optional Extras: Digital pressure gauges
Controls
- 1/4” BSP (1/4” NPT, M20 x 1.5 or other if specified)
- Release Valve
- Top cover of reservoir chamber
- Fine Adjust Handles (turn clockwise to increase pressure)
- Liquid reservoir
- Coarse adjustment handle
- Screw for fitting cover
- Isolating Valve (isolate the DUT from pressurizing system)
Pressure Routine
Operation
Preparation & Maintenance
Basic Operation
Operating Notes, Precautions & Troubleshooting
Operating Notes/Considerations
To produce stable and high pressure measurements using a hydraulic pump, the
gas within the calibration system needs to be removed. Hydraulic test pumps
use various types of fluids to generate high pressures. Because gas is much
more compressible than liquid, purging most if not all the gas out of the
system will allow for maximum pressures to be generated.
The following steps describe the procedure to purge the gas from a 7195 test
pump:
- Ensure the pump, reference standard, and device under test (DUT) are securely connected to the calibration pump.
- Close the vent valve and screw out the main screw press. You should see a vacuum being pulled on your reference and DUT (assuming the reference and the DUT are able to be used for vacuum measurement).
- Open the vent valve, wait for the pressure to settle to zero, and screw in the main screw press. As you do this, you may see bubbles emerge in the medium reservoir which is a good indication that gas is being pushed out of the system.
- Close the vent valve and repeat steps 2 and 3 one or two more times.
- Close the vent valve and unscrew the main screw press half way out. Then open the vent valve to zero the measurement.
- Now, you are ready to close the vent valve and generate pressure.
Notes on Stable Measurements
As pressures are generated to the desired test point it is common to initially
observe a fairly rapid decrease in pressure. Initially, you may conclude that
this is a pressure leak but what you are likely observing is called the
adiabatic effect. This effect is defined as a gain or loss of heat within a
system and its environment. When a gas is compressed under adiabatic
conditions, its pressure increases and its temperature rises without the gain
or loss of any heat. This happens when the screw press of a pump compresses
the fluid volume, thus resulting in an increase in pressure but also an
increase in the temperature. As the increase in pressure stops the temperature
generated from the screw press dissipates. If the volume is held constant and
the temperature decreases so also will the pressure decrease. So this initial
decrease of pressure is in fact a result of the temperature settling from the
adiabatic heating effect generated from the screw press of the pump.
Other sources of instability that also impact the pressure measurement are
instabilities in room temperature and changes in volume. Because temperature
is a factor of pressure as the entire pressure system changes temperature due
to the room temperature changing the true pressure value will also change. The
same can also be said of the pressure volume. With an increase or decrease of
pressure volume the true pressure value will see a correlated change. Volume
changes with pressure systems are usually not very noticeable except at high
pressures. At high pressures, the materials where the pressurized volume is
contained will slightly expand causing the volume to expand and the pressure
will decrease. This is particularly evident when using flexible hoses at high
pressures. Using metal tubing as opposed to flexible hoses will yield higher
stability as metal is less likely to allow for the volume to expand when under
high pressure.
Operating Precautions
- Do not exceed the safety pressure limit
- Close the valves and tighten plugs when 7195 is being transported
- Always open the release valve during operation
- Change contaminated media immediately
- Do not allow the media level to drop below the mid line of the reservoir when the 7195 is placed horizontally
- Do not shift the selector to vacuum mode whilst under pressure
- Do not over tighten connectors
- Keep outer threads clean
- Store the pump in a dry and clean environment
Troubleshooting
Warranty and Servicing
Warranty
Time Electronics products carry a one-year manufacturer’s warranty as
standard.
Time Electronics products are designed and manufactured to the highest
standards and specifications to assure the quality and performance required by
all sectors of industry. Time Electronics products are fully guaranteed
against faulty materials and workmanship.
Should this product be found to be defective, please contact us using the
below details. Inform us of the product type, serial number, and details of
any fault and/or the service required. Please retain the supplier invoice as
proof of purchase.
This warranty does not apply to defects resulting from action of the user such
as misuse, operation outside of specification, improper maintenance or repair,
or unauthorized modification. Time Electronics’ total liability is limited to
repair or replacement of the product. Note that if Time Electronics determine
that the fault on a returned product has been caused by the user, we will
contact the customer before proceeding with any repair.
Calibration and Repair Services
Time Electronics offers repair and calibration services for all the products
we make and sell. Routine maintenance by the manufacturer ensures optimal
performance and condition of the product. Periodic traceable or accredited
calibration is available.
Contacting Time Electronics
Online:
Please visit www.timeelectronics.com and
select Technical Support from the Contact links. From this page you will be
able to send information to the Time Electronics service team who will help
and support you.
By phone:
+44 (0) 1732 355993
By email:
[email protected]
Returning Instruments
Prior to returning your product please contact Time Electronics. We will issue
a return merchandise authorization (RMA) number that is to accompany the goods
returning. Further instructions will also be issued prior to shipment. When
returning instruments, please ensure that they have been adequately packed,
preferably in the original packing supplied. Time Electronics Ltd will not
accept responsibility for units returned damaged. Please ensure that all units
have details of the service required and all relevant paperwork.
Send the instrument, shipping charges paid to:
Time Electronics Ltd
Unit 5, TON Business Park, 2-8 Morley Road,
Tonbridge, Kent, TN9 1RA.
United Kingdom.
Tel: +44(0)1732 355993 Fax: +44(0)1732 350198
Email: [email protected]
Web Site: www.timeelectronics.com