James Fisher Subsea Excavation delivers pipeline trenching
Completing a pipeline project in the Bahamas, JFSE delivered a trenching project for Cal Dive International Inc.
James Fisher Subsea Excavation's T8000 mass flow excavation spread was mobilized on board the Cal Dive Pipelay Barge Lonestar. The workscope was to trench in 10 pipelines offshore the Bahamas.
10 pipelines had been laid in close proximity to each other and the minimum requirement was trenching them level with the seabed. The pipeline details were as follows:
- 4 x 30" (35" OD)
- 4 x 24" (28" OD) - one of these had a 4" piggy back line
- 2 x 14" (16 1/2" OD)
A total length of approximately 2300' of each pipeline was to be trenched.
All 10 pipelines were trenched to specification in 36 1/2 hours, an overall progress rate of 3.2m/min. Due to the soft nature of the soils and the pipelines being laid close to each other, it was possible to trench more than one pipeline in at a time. The non-contact method of excavation produced by JFSE's tools was ideal in this situation, where a sled or plough could not be used.