Phuel 145-4427-HV0, Руководство пользователя

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User Manual
Grease Head
OPS-4427 Rev A 7
3.2.4 Tension Pack off
The pack off assembly allows a rubber seal to be made against static wire in
order to prevent the escape of well fluids if the grease seal is lost. In some
Grease Heads the packing can become energised by the flow of the grease
and can cause it to grip down on the wire and prevent or restrict the running of
the wire. The Phuel pack off element is located at both ends and is held in
tension to prevent this kind of problem from occurring.
3.2.5 Lower Pack Off
There is also a lower pack off assembly which is attached below the lower
flow tube to provide a lower pack off assembly. This is used to quickly re-
establish the grease seal during operations rather than circulating the grease
all the way to the BOP.
The lower pack off would be closed with the upper one and grease circulated
through only the greasehead length without any losses in to well below. This
will provide a smaller volume for circulation and may eliminate the need to
close the BOP on the wire
– thus saving valuable operational time.