Cleanliness Verification

The challenge

Tube cleanliness verification has become a key demand from clients. Mechanical decoking and descaling operations have typically relied on judgment and subjective interpretation of pressure/flow indications. For some time the industry has been obliged to accept this, but has been seeking a more reliable method of scientific evidence. 

Within the mechanical cleaning process various techniques and indications are used to judge the internal cleanliness of process tubing. These may include: 

  • Enhancement of volume flow rate 
  • Amount of fouling removed 
  • Return water colouration 
  • Use of ‘sizer’ pig 
  • Boroscopic examination 

Such measures can be rather qualitative, judgmental and subject to human error, as well as exaggerated claims. 

The solution

By deploying a Cokebusters’ intelligent pig it is now possible to ‘see’ inside the entire process and verify the degree of cleanliness. 

Our intelligent pig is deployed during and following mechanical cleaning operations using the same connection arrangements. In a time efficient operation the data gathered from the intelligent pig can be used to accurately locate and verify thickness of residual internal coke or scale.  Equipped with this knowledge, the mechanical cleaning operators are then able to perform a safer and more efficient service by concentrating their efforts only on the process tubing where fouling remains.

A critical advantage is the practice of combined service which Cokebusters patented in 2007. Our mechanical cleaning operators and inspection technicians are colleagues working together, communicating seamlessly. In newly constructed assets an inspection can be carried out to provide a baseline which can be very helpful as a record for future operations. In certain circumstances a pre-decoke/descale inspection can be carried out; more usually the piping inspection runs in harmony with the mechanical cleaning to bring the operation to a successful conclusion providing coke/scale removal verification. 


  • Eliminates the judgement based approach to cleaning 
  • Scientifically informs the end user 
  • Provides for precise location of fouling, both longitudinally and circumferentially 
  • Enables quantification of fouling thickness 
  • Identification and location of hotspots 
  • Maximises cleaning efficiency and speed 
  • A full comprehensive report illustrates the results in detail