Solutions Engine

Weld Defects

Pipelines often contain weld defects from construction, such as missed weld passes or lack of fusion, that can lead to problems like cracks and crack-like defects. Under conditions of high pressure or shifting landscape, these weld defects can cause cracking or other integrity issues that may eventually lead to pipeline failure. 

TDW offers a suite of solutions to help pipeline owners and operators detect weld defects such as misalignment, crack-like features, missed weld passes, lack of fusion, and corrosion. These services enable the Offshore Pipeline market to:

  • Detect weld defects before they lead to failure.
  • Perform a comprehensive assessment with no damage to the pipeline.
  • Monitor defects and prioritize repairs.
  • Repair defects without pipeline shutdown.
  • Keep lines running safely and efficiently, in compliance with company, industry, and regulatory standards.



Pigging assists Offshore Pipeline operators in assessing weld defects by cleaning the pipeline prior to evaluation with inline inspection tools, helping to improve data capture and providing the most accurate information about necessary repairs. In addition, as isolation operations are often necessary to facilitate the repair of pipeline defects, pigging prior to the isolation is essential to success. By removing built-up liquids, contaminants, and deposits on the pipe wall, operators can help ensure a flawless isolation. This translates into a quicker turnaround and less downtime.

  • VANTAGE® V cleaning pig  – Multi-use pig designed to remove both hard, crust-like, and soft, gummy deposits, as well as ferrous materials.
  • 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 a bypass groove that effectively removes paraffin and other soft deposits that could lead to corrosion.
  • UNISPHERE™ pig – Provides heavy-duty removal of liquid hydrocarbons and water from pipelines and piping systems.


In the Offshore Pipeline market, risk reduction is of utmost importance. TDW offers safe, proven hot tapping and plugging (HT&P) solutions for a wide array of pipeline defects and maintenance challenges from dents to corrosion to valve failure.

TDW technicians, who have a long track record of successful offshore projects around the globe, ensure that the work entrusted to the company is done efficiently with minimal interruption to product flow.

Whether operators need an emergency pipeline intervention or topside maintenance during a planned shutdown, HT&P offers safe and proven solutions for getting the project completed. The process incorporates a high 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.

TDW isolation technology plays a critical role in this process and, when combined with a temporary bypass, allows repairs to be performed without the need to stop product flow. The STOPPLE® Train Plugging System, for example, uses double block and bleed technology to help increase efficiency and safety during pipeline maintenance and repair. The system is able to create a double block and bleed seal through a single fitting – 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 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, they can rely on the TDW line of equipment and consumables. The Subsea 1200RC tapping machine, for example, is a topside-driven hot tap machine that can be safely operated down to a depth of 3,000 meters (9842.5 feet). The machine has proven to be a highly reliable shallow and deep-water solution.


TDW provides Offshore Pipeline operators non-destructive in-ditch assessment to verify inline inspection (ILI) results, and to detect and size girth weld and long seam anomalies.

  • Phased array – An advanced ultrasonic inspection used to detect and size planar anomalies, such as long seam cracks. This evaluation allows for permanent documentation of acquired data for anomaly growth monitoring.
  • Conventional shear wave ultrasound  – This technology detects and sizes planar anomalies that are perpendicular to the pipe wall.
  • Magnetic particle inspection (MPI) – A combination of magnetic flux leakage (MFL) testing and visual inspection, this evaluation checks exposed pipe for surface anomalies, such as long seam cracks.