Solutions Engine

Line Relocation

Most pipeline infrastructure was initially established in rural regions far from population centers. With time, however, expanding development has begun to encroach on what were considered low density areas. As a result, pipeline owners may be required to reroute pipeline sections due to class location changes.

Relocations may also be necessary to accommodate environmental and historic preservation requirements and to allow for public works projects, including road and highway construction. Pipeline owners and operators may also perform line relocations to expand their system or link multiple pipelines together.

For Gas Transmission operators facing any of those scenarios, TDW can help prepare lines for relocation through a variety of pigging services, then perform hot tapping and plugging (HT&P) operations so work can be completed with minimal flow interruption.



Pigging technology is used to displace products prior to pipeline relocation. Most displacement pigs from TDW are equipped with RealSeal® urethane cups – one of the industry’s most effective seals – for optimal performance and two to three times longer life than regular cups.

Displacement pigs include:

  • UNISPHERE™ pig – Heavy-duty inflatable sphere that removes liquid hydrocarbons and water from pipelines and piping systems.
  • REDSKIN™ foam pig Tough and abrasion-resistant, used for dewatering, air removal prior to hydrostatic testing, and drying after hydrostatic testing.
  • 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.
  • ULTRA™ pig – All-urethane pig that is batching- and displacement-capable.                
  • X-Pig® multi-purpose utility tool Flexible and versatile all-urethane pig that can negotiate tight pipeline turns; appropriate for cleaning, batching, and displacement operations.               
  • VANTAGE® + pig Can be used for batching and displacement; flexible in tight bend pipelines; can traverse a 20 percent reduction in interior pipe diameter.

Technical assistance is available from TDW subject matter experts for special circumstances or if the path to a solution requires consultation.


In the Gas Transmission market, where pipeline shutdown may not be an option, hot tapping and plugging (HT&P) technology allows operators to complete pipeline replacements and modifications – from making lines piggable to line lowering and relocations – with minimal flow interruption. TDW HT&P solutions protect customers’ revenue stream while minimizing risk – and are available for a wide spectrum of pipelines, environments, and products. 

The HT&P process incorporates a high pressure fitting, valve, tapping machine, and isolation technology – 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 – which only requires a single pipeline tap – reduces 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 contained 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 TDW equipment and consumables. 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.