In-line Inspection

In-line inspection

To keep pipelines operating efficiently, thorough and reliable in-line inspection is essential. Our in-line inspection department is a key part of PMC, where our highly experienced team works with specialist partners to provide a complete pipeline-inspection service. 

We offer a full range of pigging services to manage in-line inspection programmes. Most importantly, these include planning and co-ordinating all inspection activities and logistics, minimising the commercial and operational impact on network operations, maintenance and construction. 

Our partners help us provide services based on specialist techniques – such as MFL (magnetic flux leakage), intelligent geometry pigging, XYZ service, and EMAT (electromagnetic acoustic transducer) inspections. They can also develop customised solutions for inspecting challenging or unpiggable pipelines. 


Preparing for inspection 

Before any specialist inspections, we use a range of preparatory pigs to check the bore, geometry and cleanliness of the pipeline. Where needed, we can provide launch and receive trolleys to help load and unload the pigs into and from the pig trap. We can also supply transmitter and receiver units to ensure a pig’s static location in the pipeline. Our pig-tracking service monitors the pig’s progress down the pipeline, monitoring its speed to keep it within its operating parameters. 

MFL inspections 

Magnetic flux leakage is a widely used, non-destructive testing (NDT) method for detecting corrosion and pitting in pipelines. It involves magnetising a ferrous metal object to saturation level, using a powerful magnetic field. Where the object has no flaws, the magnetic flux remains undisturbed. Where there is internal or external metal loss, the flux leaks from the object. 

High-resolution geometry inspections 

Using high-precision geometry mapping and dent sizing, we gather data that forms the basis of an accurate stress analysis. We can combine this high-resolution inspection with MFL inspections. 

Our in-line inspection services at a glance 

  • Planning pigging programmes from start to completion. 
  • Reviewing initial pipeline questionnaires, and providing guidance on selecting and sequencing preparatory pigs. 
  • Installing and removing portable pig traps. 
  • Interpreting the causes of any damage to pigs, and advising on how to proceed. 
  • Providing all preparatory pigging equipment needed for each specific situation, including launch and receive trolleys. 
  • Live pig tracking to monitor a pig’s progress along the pipeline route. 
  • Interpreting inspection reports, and offering specialist consultancy, including software training. 


Pig launch and receive trolley hire

PMC provide launch and receive trolleys to load and unload preparatory pigs from pig traps ranging from 12" to 48".

Pig tracking and monitoring

We offer pig tracking services: our technicians can confirm pig velocities and can pin-point the location of a pig travelling through a pipeline.