Bi-Directional Disc Pigs are the most commonly used pig designs for many pipeline pre-commissioning and commissioning operations, as well as operational cleaning. Their ability to run in either direction plus their multi-application capabilities makes them highly versatile tools.
Polyurethane discs are mounted to a steel ‘mandrel’ pig body and secured with high tensile fixings. Selection of metallic components and high strength polyurethane wear components is done on a job-by-job basis, to ensure that each pig is project-specific.
Bi-Di disc pigs can be fitted with the following optional extras: -
- Check Valve Passage Bumper Noses and Guide Ribs
- Articulated Joints for Dual-Module Design
- High Power Neodymium Magnets for Signalling and Ferrous Debris Collection
- Metallic or Nylon Brushing Elements (Circular or Sprung Mounted) to suit coated or uncoated pipelines
- High Friction Pipeline Isolation Discs for pressure holding and sealing applications
- Dewaxing / Descaling Pads
- Polyurethane Bumper Noses
- Tracking Device Housings
- Long Run / Low Wear Polyurethane Components
- Stainless Steel Metallic Parts
- Spring-Mounted Support Wheels
- Pluggable Bypass Ports and Jetting Heads
- Smart Gauging Tools
- Environmental Logging Tools
Typically each new pipeline project will use flooding, cleaning, gauging and dewatering pigs during the pre-commissioning phases of the pipeline construction. These pigs are usually back-loaded into subsea laydown heads and are launched remotely. This operation suits disc pigs, which have the ability to be loaded backwards into the launching head and then driven out and into the pipeline.
Similarly, the pigs can be received forwards into the receiving head and then reversed out once the head has been recovered to the surface.
Disc pigs also possess an ability to be configured for aggressive cleaning operations or high sealing dewatering operations, by simply increasing the number or thickness of discs. This can often be done without affecting the overall pig length.