An interview with Erik Dietrichson, Manager - Eastern Region Well Intervention Service, FMC Technologies
Perspectives and development of the RLWI business
Riserless Light Well Intervention or RLWI – is the term used to describe the method
for performing inspection and maintenance of subsea wells from a monohull vessel by
sluicing a toolstring suspended in a wireline into the subsea well under full pressure,
but without using a high pressure riser. RLWI is a cost efficient method as it can be
performed from monohull vessels rather than costly drilling rigs. Wireline operations
are used to perform production logging by measuring the locations of liquid in-flow and
water content, to install a plug to isolate intervals with high inflow of reservoir water
and to re-perforate the well casing by use of explosives to establish a new production
interval at a higher level. It is also possible to increase the production rate from a well by
removing scale growth that will reduce the well’s flow area. Another routine operation
is to install a so-called insert-down-hole-safety-valve, to replace the function of the
initially installed safety valve.