Subsea 7 has filed a patent for a method of manufacturing a pipeline with electrical cables. The method involves monitoring the insulation resistance of the cables while they are being applied to the pipeline and raising an alert if a fault is detected. This allows for quick detection and rectification of faults before they become inaccessible. The process can continue unless a fault is detected. GlobalData’s report on Subsea 7 gives a 360-degree view of the company including its patenting strategy. Buy the report here.
According to GlobalData’s company profile on Subsea 7, ship loading/unloading cableways was a key innovation area identified from patents. Subsea 7's grant share as of September 2023 was 56%. Grant share is based on the ratio of number of grants to total number of patents.
Insulation resistance monitoring for manufacturing pipelines with cables
A recently filed patent (Publication Number: US20230302751A1) describes a method and arrangement for manufacturing a pipeline with cables applied to it. The method involves monitoring the insulation resistance of the cables while they are being applied to the pipeline and raising an alert if a fault is detected. The method also includes stopping the movement of the cables relative to the pipeline upon raising the alert.
The method further includes advancing the pipeline or a cable lay apparatus while applying the cables and performing insulation resistance monitoring. If a fault is detected, the advance of the pipeline or cable lay apparatus is stopped. Additionally, a process is performed to cover the pipeline and cables, but the advance of the pipeline is stopped before the fault in the cables is covered by the process.
The method includes advancing the pipeline through an inspection zone where the cables applied to the pipeline are accessible before they are covered by the process. If a fault is detected in the inspection zone, it can be rectified after stopping the advance of the pipeline.
The inspection zone has a specific length, and the alert is raised within a calculated time period based on the velocity of the pipeline. The method allows for continuous advancement of the pipeline unless a fault is detected in the cables.
Insulation resistance monitoring is repeated on the cables, and an alert is raised if a fault is detected in successive monitoring operations. The monitoring is performed by a monitoring unit connected to the leading end of the cables, which can be located within or ahead of the leading end of the pipeline.
The monitoring unit can transmit an alert signal to a remote alarm or control unit in an upstream direction. The alarm unit is positioned to convey the alert signal to a location where the cables are accessible, while the monitoring unit is located downstream at a location where the cables are substantially inaccessible.
The patent also describes a cable monitoring arrangement that includes an inspection zone, an insulation resistance monitoring unit connected to the cables, and an alarm unit positioned to convey the alert signal to the inspection zone. The monitoring unit can have a wired or wireless communications interface with the alarm unit and can be remotely configurable.
Overall, this patent presents a method and arrangement for manufacturing pipelines with cables applied to them, ensuring that any faults in the cables are detected and addressed before they are covered by a protective process. The monitoring system allows for continuous advancement of the pipeline while monitoring the insulation resistance of the cables.