A new liquefied natural gas (LNG) project in Western Australia required pre-commissioning pigs to be pre-loaded inside a subsea launcher. A critical requirement of the client was that the pig tracking system must retain its battery life over a long period. Moreover, it has to be environmentally friendly and with a proven track record.
To ensure that pig tracking transponders would be reliable and that the eventual pig tracking process would be effective, the firm turned to pipeline solutions provider T.D. Williamson (TDW) and its SmartTrackTM pig tracking system.
The SmartTrack system is a two-way communication system that is designed for tracking inline tools and pigs as they travel inside onshore, topside or subsea pipelines. Using extremely low frequency (ELF) signals, the system is an alternative to the traditional isotopes that tend to be used for inline pig tracking operations.
The system has been used extensively to track pigs during dewatering, cleaning and gauging operations in pipelines during pre-commissioning works. For subsea operations, the system’s transceivers can operate in depths of up to 2500 m (8200 ft).
Of key importance in this instance, SmartTrack transponders have a long battery life and have a demonstrated their effectiveness with a history of reliably reactivating after lengthy idle periods.
According to Thomas Hans Barlaug Bergsland, TDW Engineering Manager, the company has calculated that SmartTrack’s transponders can remain in dormant mode for up to 767 days. Ongoing testing conducted by TDW indicates a 100% success rate in reactivating the transponder from the dormant state. In addition, the transponders can be easily mounted onto pigs without affecting their design or functionality.
Use on the LNG project
The LNG plant in question gathers and partially process gas from various offshore fields in the West Carnarvon Basin, before delivering it to an onshore facility.
In 2014 – well before the pipe connecting the on and offshore infrastructure was scheduled to be laid – the operator fitted the SmartTrack equipment into the bodies of eight bi-directional pigs, intended for use in dewatering, drying and purging two 24 in. production lines and two 14 in. utility lines.
After the lines were laid and the transponders successfully reactivated, pigging operations commenced. The pigs were retrieved from the lines in 2016, 21 months from the 2014 start date.
To track the pigs that were fitted with the SmartTrack transponders, TDW also supplied a subsea remote transceiver for confirmation of pig launching and a topside transceiver for tracking pigs from the platform side.
TDW trained the field firm’s personnel on how to handle its SmartTrack equipment.
Read the article online at: https://www.worldpipelines.com/equipment-and-safety/08122016/tdw-pig-tracking-system-used-for-lng-project/