Performing
Junkan Wang,
Ali Mirzaee-Sisan,
Jens Petter Tronskar,
Dag Øyvind Askheim and
William A. Bruce, DNV GL,
provide an overview of pipeline
repair state-of-practice, including
welding considerations,
technologies and techniques.
R
epair of oil and gas pipelines is a
major operating expense (OPEX). Loss
of production time due to repair
operations can equate to millions
of dollars per day in lost revenue. As a result,
pipeline ‘live repair’ – i.e. repair operations
without any downtime – is often preferred.
The extent of possible damage can vary
from insignificant, minor dents to a fully buckled
or ruptured pipeline. The type and extent of
damage governs the repair solution and repair
preparedness strategy. For extensive damage
of large sections of the pipeline, repair options
are usually limited to cut and replacement
using hot tap and bypass with substantial OPEX
implications due to lost production time.
For most local damages, such as external or
internal corrosion and mechanical damage on a
local scale (i.e. dents, wrinkles, buckles or girth
LIVE
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