Cost Comparisons

Cost Comparisons

Case Study on Rope Access Techniques for CUI Inspection – National Petroleum & Refining Association Document # MC-02-87

THE USE OF ROPE ACCESS TECHNIQUES TO INSPECT FOR CORROSION UNDER INSULATION ON TOWERS IN AN OPERATING PROCESS PLANT

Site # 1 Work Scopes

CUI visual and ultrasonic inspection of tower (8′ diameter x 175′ height) and its 18’ overhead line.

  • Remove insulation around all insulation penetrations not accessible by platforms (approximately 60 nozzles and support clips).
  • Remove insulation 2 feet above and 1 foot below all stiffening rings (11 support rings).
  • Remove insulation at 9 locations on the 18-inch overhead line.>/li>
  • Visually inspect and take Ultrasonic Thickness readings, clean and prepare surface using hand tool methods, coat with primer and top coat, and re-insulate all uncovered areas.

No safety incidents occurred

Site_1_Cost_Comparison

Site #1 – 65% cost savings using Rope Access methods as compared to conventional scaffolding based on fixed price quotes.

Site_1_Schedule_Comparison

Site #1 – 32 days for completion verses an estimated 75 days for scaffolding.

Site # 2 Work Scopes

CUI visual inspection of tower (10′ diameter X 100′ height) and overhead line (12’ diameter x 115′ length).

  • Remove insulation around all insulation penetrations not accessible by platforms (approximately 15 nozzles and support clips).
  • Remove 100% of insulation from the 12-inch overhead line.
  • Visually inspect and take Ultrasonic Thickness readings, clean and prepare surface using hand tool methods, coat with primer and top coat, and re-insulate all uncovered areas except for the overhead line.

No safety incidents occurred

Site_2_Cost_Comparison

Site #2 – 45% cost savings using Rope Access methods as compared to conventional scaffolding based on fixed price quotes.


Site #2 – 7 days for completion verses an estimated 21 days for scaffolding.

Conclusion

  • Rope Access is a safe and effective method for executing work at elevated locations.
  • The overall safety exposure is reduced due to the elimination of scaffolding erection and dismantlement.
  • Work can begin quicker because the scaffold erection time is eliminated.
  • The quality of workmanship is equivalent to the quality of work performed from scaffolding.
  • The total cost of the job is significantly reduced due to the elimination of scaffolding costs.
  • Overall reduced number of man-hours to complete the job.