Brooks Instrument 1255A, Installation & Operation Manual

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Section 6 Maintenance
Reassembly Procedure
1. Use the reverse of Steps 1 through 5 of the disassembly procedure to
reassemble the meter.
2. Prior to installing the needle control valve assembly make certain that
the valve stem is turned completely counterclockwise (full open position) to
prevent damage to the valve seat. Packing seats should be examined for
damage or deterioration and replaced if necessary.
3. Make sure that the tube seats firmly on the packing seats and does not
overlap onto the end block.
4. The jack screw and plug serve to axially compress the tube seat gasket
and exert a uniform pressure on the metering tube to prevent any
possibility of leakage. Do not overtighten the jack screw.
5. After the flowmeter has been reassembled, it is important that it be leak
tested with air at a minimum pressure of 15 psig at room temperature.
6. To detect leaks, brush soapy water around all possible leak points (tube
packing, connections, and seal spindle) and check if bubbles are being
formed. Should a leak be detected, tighten that particular joint to see if the
leak can be stopped. If the leak persists, disassemble the area involved
and check for dirt or damaged elastomer. Clean and replace elastomer.
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