How to select Corrosion Monitoring Locations (CMLs) from 6000 ISOs


IRISNDT’s Canadian Mechanical Integrity group was tasked with selecting CMLs for a SAGD facility which had equipment covered in 6000 ISO’s. How could we complete this task within one month? With the support from the Maxi-Trak™ Field Services (MTFS) Walkdown feature. The process used is described below.


To begin, projects such as this entail performing criticality assessments (CAs) of the equipment.  Otherwise, how can the areas prone to corrosion be identified?  During these CAs, we identify the equipment (tanks, vessels, and piping) which pose a greater risk to the site were they to fail.  This selection is based on our review of the different processes in SAGD facilities (knowledge of the process fluids, temperature, damage mechanisms, corrosion rates, and others).

After the CAs are completed, our Systems group downloads the ISOs into the Maxi- Trak™ Field Services software. They sync the data to multiple Toughbook tablets loaded with Maxi-Trak Mobile (MTM).  MTM loaded tablets in hand, we walk the lines with printed P&IDs to select CML locations.  

Walking with numerous printed ISOs to mark the CMLs would be an impossible task to accomplish within the finite time frames in which these projects must be completed.

During the walkdowns, IRISNDT personnel:

  • Use the P&IDs to identify a starting location.
  • Follow the piping/equipment until we identify areas where CMLs are needed.
  • Look on the P&ID and finds the line number.
  • Use MTFS Walkdown loaded tablets to look up the line number (all ISOs are stored by line number).
  • Make sure the line we see looks just like what the ISO indicates.
  • Place arrows indicating the inspection point and a CML number within MTM loaded tablets.
  • Take geo-referenced photos of the identified inspection point.
  • Mark the same CML number on both printed P&ID pages (for future reference) and the tablet ISOs.
  • Track modifications from the original construction ISOs with the MTFS Walkdown app.

With the MTFS Walkdown app and the MTM loaded tablets, IRISNDT personnel photograph the chosen locations, and tie the photo identification to that of the ISOs.

IRISNDT’s MTFS and MTM software is imperative for this work with numerous ISOs.  Our Mechanical Integrity Group is here to support your projects involving Mechanical Integrity Programs (MIP), Corrosion Control Documents (CCD), Criticality or Risk Assessments, and CML Selection and Optimization programs, etc.