EMAS Chiyoda Subsea (ECS) has conducted a metrology campaign in offshore Western Australia with survey software provided by subsea technology company Sonardyne International Ltd.
The project took 26 hours to complete.
Apache Energy awarded the contract to global offshore construction company ECS to install infrastructure at the Jullimar natural gasfield.
The contract includes installation of two manifolds, connected by five 30m vertical spools and five 80m horizontal spools.
Underwater metrology measurements must be accurate on the basis of successful fabrication and installation of spools and jumpers are conducted.
Surveyors estimated that to gather the ten metrologies at Julimar could take around 60 and 80 hours. However, using Sonardyne’s Connect software streamlined and completed it in 26 hours.
Sonardyne International developed Connect software in partnership with survey engineering company 4D Nav.
It accelerates metrology campaigns by introducing expert settings, automated data collection and fast processing of acoustic measurements from planning to report delivery.
This software not only saves time and money, but also decreases the risk of spool pieces getting fabricated incorrectly.
The campaign was conducted from ECS’s heavy-lift, deepwater, multi-lay vessel Lewek Constellation that operated with Sonardyne’s sixth generation acoustic positioning transponder hardware.
The equipment was positioned on the seabed and placed in survey receptacles attached to the various structures.
ROV-friendly transponders enabled it to move around the site and align itself to each structures’ north.
The survey team collected depth and profile data using an ROV held digiquartz depth sensor with heading and inclination data at each survey receptacle. Collected information was analysed as one data set.
The shallow water depth at the site necessitated Connect’s ability to edit the sound velocity for baseline observations and reprocess multiple metrologies to evaluate the effect.
After quality check, each spool metrology was processed and a final report was generated.
The final report included summary of the results, slant range, depth differences, attitudes and details of calculations.