WEBTEC HT Series Bedienungsanleitung Seite 3

HT Series Portable Hydraulic Testers have been designed for easy connection to a hydraulic
circuit so that flow, pressure and temperature can be readily checked. Testers can take full back
pressure up to 210/420/480 bar (depending on model) and the built-in loading valve enables
many of the operating conditions to be simulated. The tester can be connected anywhere in the
hydraulic system to test pumps motors, valves and cylinders in both flow directions.
Bi-Directional Flow Testing
The loading valve gives smooth control of pressure in both flow directions and is protected in
both flow directions by two replaceable safety discs which are designed to rupture at
approximately 7 bar (100 psi) over the maximum working pressure. When these discs rupture,
the oil by-passes the loading valve at low pressure and continues to flow freely through the
hydraulic system. A range of pressure safety discs are available to protect both the tester and
other components in the hydraulic system.
Although the bi-directional tester can be used in both flow directions, the preferred direction is
indicated by the larger arrow on the panel. When the tester is used for reverse flow tests, slightly
lower accuracies may be obtained depending on the oil viscosity, density and compressibility.
The tester should be connected to the hydraulic circuit by means of flexible hoses 1 - 2 metres
long. The use of quick-disconnect couplings can save time. Make sure the hoses are long
enough so that the tester can be used conveniently on the machine. The hoses and fittings at
the inlet to the tester must be of adequate size for the flow being tested. Elbows, rotary
couplings etc., at the inlet and outlet ports of the tester should be avoided to ensure accurate
readings.
The use of the flexible hoses will help to isolate the test unit from vibration which often exists.
After installing the Tester it is important to ensure that all connections are tightened and the oil
can flow freely throughout the hydraulic system BEFORE running the machine at full speed.
Check that the circuit is correctly connected and any shut-off valves are opened. Also quick
disconnect couplers MUST be open. IMPORTANT: Start the pump momentarily to ensure there
is no obstruction which could cause pressure build up.
Testers have an automatic electronic system which shuts the power off after approximately 20
minutes should you forget. To reactivate the tester, turn the selector switch to the "OFF /
RESET" position, then return the switch to the required test position.
The standard Webtec Hydraulic Testers are designed for use with mineral oil having
reasonable lubrication properties. They are not suitable for use with water or fluids with a high
water content. If a tester is used with water it should be flushed immediately after use with
white or methylated spirit or similar and then flushed with mineral oil to minimise any internal
corrosion. This may avoid an expensive repair. Damage to a tester from the use of a non-
approved fluid invalidates our normal warranty.
Introduction
Do not use with water
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