2.6 COMMISSIONING
The first year of operation is crucial, because when the pipe is put into service, all debris is pushed
downstream, and contaminates the valves along it’s travels. With time, the pipe gets cleaner and initial
problems disappear. Strainers or filters should be installed upstream of all soft seated valves.
The same recommendations regarding grease injection for flushing (see 2.4) apply for commissioning. By
refilling the grease channels multiple times, the dirt is gradually pushed out of the seats. Provided that
the grease is properly chosen (see 2.4), it will not damage the valve, and to a certain extent will shield
the seats from contamination. Regular cycling is also important, for two reasons: to prevent the seats
from getting stuck, and to distribute fresh lubricant over the seating surfaces of the ball and seats. Once
the seat is greased, it is a good idea to pump fresh grease into the seat to expel any debris laden grease
(see 2.4.3) before cycling the valve to avoid damage to soft seat inserts. Many operators prefer not to
grease seats even during commissioning as the grease can attract debris which can damage the seats if
the valve is then turned. Also grease channels can become blocked if grease hardens. However, if the
service is dirty the seats will damage either way, hence many users find regular greasing delays the
damage. Should you need to apply grease to seats, ensure you then inject fresh grease to dispel any
grease which may have attracted contaminants and then partially stroke the valve multiple times to
remove as much grease as possible from the seats. After commissioning, once you believe the service is
clean you can inject a suitable grease line flushing agent and then partially stroke the valve again. You
should consult a valve maintenance specialist as different service, media, pressures, temperatures, etc.,
can require totally different practises. APV recommends the following programme for start up: -
1. For the first year, inject a small amount of grease into the seats before turning the valve, every time.
2. Cycle the valves periodically as follows:
• For the first month, every week.
Australian Pipeline Valve - Installation, Operation and Maintenance Manual
10
SIDE ENTRY 3P TRUNNION BALL VALVES API6D STANDARD - BVF100 SERIES
Note
Remember that ball valves in natural gas service are like the human body; they
need ‘exercise’. Keep moving them and lubricating them, and you will have fewer
problems. Do not let them have a sedentary life.
Natural gas is not usually clean. Natural gas may carry condensates and dirt that
gets trapped in the valves, and may damage the internal parts. Also, operation of
the valves becomes more difficult. It is true that plant sites do install filters in their
system, but experience has proven that no system is perfect. The internal parts of
the valve can be partially protected using judicious amounts of grease to fill the
cavities. However, other than when flushing (see 2.4.3) or if there is seat leakage,
or if valve cannot be opened, no grease should be applied via seat sealant injectors
to soft seats as it will attract debris and cause damage. A soft seated valve is
always at risk if service is not clean.