Subsea 7 has been granted a patent for a method of creating a weld between a liner and an electrofusion fitting in a section of lined pipe. The method involves using an electrofusion fitting with at least one heating element that is electrically isolated from the inner surface of the fitting. An induction coil is placed within the fitting near the heating element, and electrical power is supplied to the coil to energize the heating element through electromagnetic induction. The temperature of the fitting is monitored, and the heating element is positioned at a location that maximizes the depth of penetration of the magnetic field induced by the current in the induction coil. GlobalData’s report on Subsea 7 gives a 360-degree view of the company including its patenting strategy. Buy the report here.
Smarter leaders trust GlobalData
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.
Method of creating a weld between a liner and an electrofusion fitting
A recently granted patent (Publication Number: US11739876B2) describes a method for creating a weld between a liner within a metal host pipe and an electrofusion fitting. The method involves selecting an electrofusion fitting with at least one heating element that is electrically isolated from the inner surface of the fitting. The end of the electrofusion fitting is located within the end of the section of lined pipe, and an induction coil is placed within the bore of the fitting near the heating element. Electrical power is supplied to the induction coil to energize the heating element through electromagnetic induction. The temperature of the electrofusion fitting is monitored during the process.
The method can also include locating the opposite end of the electrofusion fitting within the end of a subsequent section of lined pipe and using another induction coil to heat a further heating element. Electrical power is supplied to the induction coil to cause heating of the further heating element through electromagnetic induction. The method can involve simultaneous heating of both the heating element and the further heating element.
To weld the fitting to the subsequent pipe lining, the method involves heating at least a portion of the electrofusion fitting associated with the heating element to a first temperature lower than the melting point of the fitting's material. Subsequently, electrical power is supplied to the induction coil to heat the same portion of the fitting to a second temperature higher than the melting point, thereby welding the fitting to the pipe lining. The method can also involve expanding the fitting to improve contact with the pipe lining and compensate for misalignment between successive pipe linings and/or host pipes.
The induction coil is long enough to locate near both the heating element and the further heating element. The method may also include providing a separate induction coil for the further heating element. Electrical power is supplied to the induction coil by passing alternating current through it, with a frequency in the range of 5 to 400 kHz. The frequency of the alternating current is controlled to heat the heating element without causing heating of the pipe.
Overall, this patented method provides a technique for creating strong and reliable welds between liners and electrofusion fittings in a pipeline, ensuring secure connections between sections of lined pipe.
To know more about GlobalData’s detailed insights on Subsea 7, buy the report here.
Premium Insights
From
The gold standard of business intelligence.
Blending expert knowledge with cutting-edge technology, GlobalData’s unrivalled proprietary data will enable you to decode what’s happening in your market. You can make better informed decisions and gain a future-proof advantage over your competitors.
GlobalData, the leading provider of industry intelligence, provided the underlying data, research, and analysis used to produce this article.
GlobalData’s Patent Analytics tracks patent filings and grants from official offices around the world. Textual analysis and official patent classifications are used to group patents into key thematic areas and link them to specific companies across the world’s largest industries.
