Leister VACUUM BOX Manual Del Usuario página 15

Preparing and commissioning the VACUUM BOX with VACUUM PUMP
• Set the required negative pressure using the regulating relief valve (8):
– During the testing phase, the negative pressure (max. 0.5 bar) can be set using the adjusting nut (10) on
the regulating relief valve (8). To do this, the adjusting nut (10) must be screwed downward in a clockwise
direction. (Fig. F)
– When the required value is set, the adjusting nut (10) of the regulating relief valve (8) needs to be locked
using the lock nut (11) (A/F 10). When in operation, the adjusting nut (10) must always be secured by the
lock nut (11). (Fig. G)
Fig. F
Testing using a VACUUM BOX with VACUUM PUMP
• The welding area must be dry and free of contamination. Dirt particles may compromise the test.
• The welding area to be tested is to be lubricated or sprayed with a liquid which forms bubbles (such as soapsuds)
directly before the test. (This is to ensure that the liquid has no unacceptable effects on the seam and the welding
material).
• Position the VACUUM BOX (2) at the point to be tested.
• Place the VACUUM BOX (2) and then push down on it so that the seam to be tested lies at the approximate
center of the longitudinal axis of the VACUUM BOX (2) (Fig. H). For extended test sections, the VACUUM BOX
(2) needs to be repositioned accordingly. When moving the VACUUM BOX (2), make sure it overlaps the testing
areas by around 10 cm.
• To enable a negative pressure to be generated, the VACUUM BOX (2) must be pressed down onto the testing
area using both handles (4). (Fig. I)
The negative pressure is displayed on the manometer (6). The negative pressure should
never exceed 0.5 bar; disregarding this may cause an implosion.
• Check the weld seam for leaks.
• The seam is regarded as being tight when negative pressure builds up quickly, remains constant for the duration
of the test, and does not cause bubbles to form in the seam.
• Use the regulating relief valve (8) to relieve the negative pressure. (Fig. K)
• Mark and repair any areas that are not tight.
Fig. H
Fig. G
Fig. I Fig. K
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