J-Lay & Pipeline Towers

Overview

Radoil has designed and built Gimbaling J-Lay Towers that allow offshore pipelines to be laid safely in deepwater. Our J-Lay Tower for OSI/Petrobras had a 58 ft. travel and another for Stolt had an 85 ft. travel (double). The J-Lay Towers land on the pipe-lay vessel and provide a platform enabling the pipeline workers to weld, test and coat the pipeline in the vertical tower. The pipeline is then fed vertically down through the moon pool to rest on the ocean floor in a J-Lay fashion. Normal S-Lay or horizontal pipe lay methods exert very high stresses on the pipeline during deepwater lays (primarily due to the pipelines own weight) when the pipeline is fed off the pipe-lay stinger in a near horizontal position. The Gimbaling J-Lay feature allows the pipeline to be constructed in the vertical position and laid along the desired path while the pipe lay vessel positions itself favorably into the wind, currents and waves. The Gimbaling also allows the pipe-lay vessel to rotate 180° to facilitate easy handoff of the SCR.

Our Steel Catenary Riser (SCR) Mast was designed to assist in the receiving and placement of the SCR from the pipe-lay vessel. The 400,000 lb. capacity SCR Mast lands on the flow-line porch of the production platform and uses a large chain to receive the SCR from the pipe-lay vessel. It then pulls the SCR up into the center well bay and positions it in the proper receptacle on the flow-line porch.

Pipeline Towers

J-Lay
Towers

Steel Catenary Riser (SCR) Mast