Main Replacement

If a pipe main cannot be repaired, replacing it without interruption to service is the next best option. From pre-isolation to commissioning, TDW employs a full suite of solutions for pipe main replacement operations.

In the Gas Distribution market, TDW services enable pipeline operators to:

  • Analyze direct and indirect measurements of the pipeline.
  • Achieve safe isolation of the pipe joint.
  • Perform replacement safely while the line remains in service.
  • Review and compare all pipeline data at the dig site.
  • Ensure a clean and efficient pipeline for service.



Pigging serves various functions throughout the Gas Distribution line replacement process, such as cleaning prior to line isolation to ensure a good seal. And after construction, pigging prepares a new pipe segment for service by removing any materials left behind during construction, including tools, contaminants, and foreign objects from the pipe wall. 

  • VANTAGE® V cleaning pig Designed to remove both hard, crust-like and soft, gummy deposits, as well as ferrous materials.
  • PitBoss™ cleaning pig – Removes soft to medium-hard deposits from internal pits, which is essential to improving the effectiveness of corrosion inhibitors.
  • WCK cleaning pig – Removes contaminants and deposits that increase resistance to flow.
  • REDSKIN™ foam pig – Used for light cleaning; one version incorporates a urethane cleaning wrap with bypass groove that effectively removes paraffin and other soft deposits that could lead to corrosion.
  • V-Jet® corrosion inhibitor pig Sprays corrosion inhibitor onto the hard-to-reach inside top portion of multi-phase gas gathering and transmission lines.
  • OptionAll™ batching pig – Designed for light cleaning, line filling and dewatering, batch separation, and liquid removal.
  • VANTAGE® V batching pig – Used for batching, displacing, and light cleaning,
  • UNISPHERE™ pig – Provides heavy-duty removal of liquid hydrocarbons and water from pipelines and piping systems.


Hot tapping and plugging (HT&P) technology allows Gas Distribution market pipeline owners and operators to complete pipeline replacements and modifications – from making lines piggable to line lowering to relocations – all while their line is in service. TDW equipment and services are engineered for safety and efficiency, allowing operators to better protect their employees and the surrounding community.

The HT&P process incorporates a low pressure pipeline fitting, valve, tapping machine, and isolation equipment, all working together to provide a safe and proven isolation solution. Once the area of pipeline that needs work has been safely isolated and evacuated, the line modification can be performed.

The full suite of isolation solutions offered by TDW plays a critical role in this process. The TDW STOPPLE® Train isolation system, for example, uses double block and bleed technology to help increase efficiency and safety during pipeline modification. The system only requires a single pipeline tap – reducing costs associated with fittings, valves, welding, and inspection services. The bleed port affixed on the line ensures that any product that bypasses the first seal is captured and evacuated through the bleed port, which creates a safe zone in high-consequence areas.

Whether operators are purchasing equipment to perform their own HT&P jobs or turning to TDW to execute the service for them, they can rely on the broad line of equipment and consumables by TDW. The company engineers and manufactures nearly every component needed for an HT&P project, and TDW tapping and isolation equipment is considered the industry standard.

TDW can also partner with operators before the work begins, providing consulting services to help them make optimum use of TDW products and services. TDW application engineers are recognized industry experts, ready to assist operators through each project phase – from start to finish.