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8 • COMMISSIONING WITH A PRESSURE OF 200% FULL LOAD, AS PER EN 81-2 AND EN 81-20.
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Pressure test as per EN 81-20, 6.3.10, and EN 81-2, Annex D, D.2, t)
A pressure of 200 % full load pressure is applied to the hydraulic system between the non-return valve and the jack included. The system is then observed for
evidence of pressure drop and leakage during a period of 5 min (taking into account the possible effects of temperature change in the hydraulic fluid).
After this test, it shall be visually ascertained that the integrity of the hydraulic system is maintained.
This test should be carried out after the test of the devices against free fall (5.6) and include any hydraulic elements included in the uncontrolled movement
protection means.
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Car with 100 % of the rated load.
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Take the lift to the top landing and write down the pressure (100%).
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Take the jack up to the end of its travel
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Operate the hand pump up to a pressure of 200%
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Let the installation rest for 10 minutes
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After these 10 minutes, note the pressure value (p1) at this time and keep the installation under pressure for a further 5 minutes and note the pressure
value (p2) in the final 5-minute period.
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For such a test to be considered successful there should be no loss of pressure greater than 10% during the final 5-minute period
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Check that there was no leakeage, nor pressure drops (taking int account the possible effects of temperature change in the hydraulic fluid).
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For such a test to be considered successful there should be no loss of pressure greater than 10% during the final 5-minute period.
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Through a visual inspection, ensure that the hydraulic system integrity is maintained.
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In exceptional circumstances, the pressure loss may be greater than 10% (due to temperature effects). After the evaluation of the correct integrity of the
hydraulic circuit, the valid test can be considered.
IMPORTANT:
As indicated in the standard EN 81-20, 6.3.10, and EN 81-2, Annex D, D.2, t), we must take into account the effects of temperature in the hydraulic fluid.
Because of its thermal expansion factor, a decrease in temperature during the test, will cause a reduction in volume of the oil inside the cylinder and
consequently a pressure drop occurs. It is advisable to perform the test with oil at a temperature as close as possible to the environment temperature, so this
effect is minimized.
There are other factors involved in a possible pressure drop during the test without entailing there are default in the circuit integrity:
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In this regard, the proper purge of the jack air is very important.
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Oil total volume of the installation.
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Temperature gradient. The greater the difference with the ambient, the greater will be the level of affectation.
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Jack locking when it is fully deployed.
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Proper assembly of frame and guide rails (unwanted frictions)
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Expansion coefficient of flexible lines.
V700 - 11/2017
MP sava3 Hidraulic Power Unit 1 ¼" 1 ½"
24/40
MTMECMPsava3_700_EN
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