Page 70: of Offshore Engineer Magazine (Oct/Nov 2014)

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Pipelines

Multiphase corrosion risk analysis

Paul Ellerton business unit manager at Apollo discusses how to

Fig. 2: Water hold-up against temperature graph at a speci? c location to highlight the time spent in the corrosion risk region.

identify corrosion risk using multiphase ? ow assurance tools.

Fig. 4: CFD images showing how hold-up (water in blue, oil in brown) altered at a

CFD on a tubing hanger.

speci? c location over time.

ging assets have a greater need 90 for more routine maintenance

Weekly average 80

A inspections. Offshore inspec-

Daily average tions, particular those involving subsea 70 pipelines, can be time, resource, and cash 60 consuming. 50

Transporting unprocessed multiphase ? uids from wells or satellite platforms 40 via steel pipelines to the processing plat- 30 form is common on many developments, but can lead to ? ow assurance issues.

20

Water hold-up (%)

In a recent maintenance inspection 10 in the North Sea, there was suspicion 0 of corrosion and wax build-up in an oil export pipeline. The 20km-long, 14in.

Fig. 1: Pipeline hold-up predictions using di