Quality of service and, therefore, level of cleanliness is the primary objective of Crest. The cleanliness of the system can be determined by a number of methods including radiography of selected tubes and video inspection. This is conducted independent of Crest and is used as verification of Crest results.

 

Crest measures cleanliness by consideration of three factors:

 

 

Comparing the final flow test results with the initial flow test results shows areas of contamination and the cleaning effect over time as shown below:

 

 

Figure 1.1 example of initial pigg run (122mm pigg from inlet to through 40off 141.3 x 5.8mm MW (ID = 129.7mm) to 6” OD tubes)

 

 

 

Figure 1.2 example of final pigg runs (135mm pigg from inlet to through 40off 141.3 x 5.8mm MW (ID = 129.7mm) to 6” OD tubes) The above instrumentation readout is monitored throughout the job and the level of cleanliness continuously evaluated.