IM-P184-09
CMGT Issue 4
10
start of text under grey section header box
start of text continuing from previous page
TRANSLATION RUN OVER
Note: Before actioning any maintenance programme observe the ‘Safety information’ in Section 1.
Warning
The body/bonnet gaskets (11a and 11b) contain a thin stainless steel support ring which may cause
physical injury if not handled and disposed of carefully.
6.1 General information
Before undertaking any maintenance on the valve, ensure any pressure is isolated and safely vented to
atmospheric pressure. The valve should then be allowed to cool. When reassembling, ensure that all joint
faces are clean.
Ensure that the correct tools and necessary protective equipment are used at all times. When maintenance
is complete open isolation valves slowly and check for leaks.
Note:
The bonnet bush and threads of the stem are packed with a high quality grease on assembly. It is
recommended to re-grease these items whenever maintenance is undertaken on the valve.
6.2 Sequence of operation for safe maintenance of plant
Please note:
that all the drawings in Steps 1 to 5 are illustrated with the flow direction from left to right.
Key
= Valve open
= Valve closed
Step 1
=
Normal operation
position
Step 2
=
Full isolation position
6. Maintenance
