User manual

1
Instructions for Use
To Establish a New Stop Position
16/36 Variable Leak Valve User Manual / 87-400-085-01 (D)
The valve is received in a closed, leak-tight position. The adjusting
knurled knobs are tightened against the handle.
During normal operation, the knobs are locked together with respect
to the fine-drive screw. To open a leak, turn both knobs together a
minimum of two full turns counterclockwise. To close a leak, turn the
knobs together until the collar botts against the handle (the stop
position has been reached).
To Establish a New Stop Position
Each time a seal is made, the valve's captured metal gasket is
compressed. High temperature bakeout accelerates the compression
of the gasket. If no change is made to the position of the knobs on the
fine-drive screw, the point of closure will gradually come closer to
the point at which the knobs and collar butt against the handle.
Eventually the stop will be engaged before a leak-tight closure is
made. When this happens, a new stop position must be established.
1. The valve must be attached to a leak detector or the system must
be equipped with gauging adequate to determine when no leak
exists.
2. With the knobs tightened against the handle, unlock the knobs
from each other by holding the inner knob and turning the outer
knob counterclockwise about four turns.
3. Turn the inner knob counterclockwise until it is locked tight
against the outer knob.
4. Turn the two locked knobs clockwise until the valve closes as
indicated on the leak detector or system gauging.
5. Turn the knobs clockwise two additional turns past the point of
closure.
6. Loosen the knobs from each other without allowing the screw to
turn. Turn the inner knob clockwise until the collar is against the
handle, then turn the outer knob clockwise until it locks against
the inner knob. The knobs are now in position to return to and
stop at a point two turns past closure.
7. After the stop has been adjusted several times, the handle must
be reset as described in para. "Maintenance".