J Tube Pigs and Pull Through Pigs for Offshore Risers
J Tube Pigs and Pull-Thru Pigs for Offshore
Pipeline Riser Cleaning
J Tube pigs or Pull-Through pigs are often used to clean and gauge a pipe section prior to the pipeline riser being pulled in. The J-Tube is usually open ended and as there is no flow, requires a pig to be pulled through the pipeline. This is achieved by passing a wire through the J-Tube and then connecting it to the front end of the J Tube pig, which is fitted with a certified pulling point. The J-Tube pig can then be winched through the pipeline. This type of pig can also be used for onshore applications where a Pull-Thru pig is required to clean a section of open ended pipe. Pigtek J-Tube cleaning pigs can be designed with certified pulling points or shackles to suit winching requirements.
During offshore installation, a J-Tube may be susceptible to fouling from marine growth and especially if a J-Tube seal or J-Tube plug is not used. Fouling may also occur from millscale or heavier rust and this type of pipeline debris should be removed by a J-Tube cleaning pig. Depending on pipeline cleaning requirements, the J Tube pigs can be fitted with a combination of polyurethane discs, steel brushes and steel scraper pins to remove pipeline scale or other hard deposits from the pipeline. Magnetic packages can also be fitted to remove any loose ferrous debris.
J Tube Pigs and Pull Through Pigs for Offshore
Pipeline Riser Gauging
During J-Tube pigging, and whilst pulling a pig through a pipeline section, it is often beneficial to gauge the internal diameter. Pipeline gauging can be achieved by fitting a J-Tube cleaning pig with aluminium gauging plates, which will deform if they come into contact with a restriction, such as a dent or a build up of hard debris within a pipeline. Pipeline gauging should be performed especially prior to any J-Tube internal inspection.