Up Time Magazine - December 2008/January 2009 - (Page 24) infrared upload Windows Open the Door to Savings A Study of a Positive, and Growing, Return on Investment by Martin Robinson A paper mill in South Carolina had a very successful infrared inspection program that management wanted to expand. However, the requirements of NFPA 70E were causing them to re-think their strategy since inspections of energized equipment was becoming more restrictive, more time consuming and more costly. Furthermore, 8% of the mill’s applications had never been surveyed due to either switched interlocks (which automatically deenergize the equipment upon opening, thereby preventing access to energized components), or to incident energy calculations in excess of 100 cal/cm2 on certain equipment (which exceeds personal protective equipment [PPE]] ratings, and would place personnel in extreme danger and open the company to OSHA fines). of the primary switchgear in their electrical distribution system which feeds one paper machine and several smaller operations within the plant. An impending ten-day shutdown increased the sense of urgency since all windows could be fitted for one machine during that period. IRISS, inc. was commissioned by the paper mill to conduct a pre-site inspection to ascertain the optimal position and quantity of windows which would give thermographers thorough visibility of desired targets. The conclusions from the initial inspection are noted in Table 1. Application 13.8 kV Primary Switchgear Secondary Switchgear Transformers (13.8 kV) MCC’s Miscellaneous Switchgear Generators Total Assemblies Inspection Compartments IR Windows In search of alternative methods of conducting safer, standards-compliant inspections, the corporate Reliability Engineer investigated how infrared inspection windows (commonly referred to as IR windows, viewports or sightglasses) might be utilized. It was determined that: • Use of Infrared Windows for routine inspections of healthy equipment did not require the elevated levels of PPE required in 70E, since as stated in 70E 100: “Under normal operating conditions, enclosed energized equipment that has been properly installed and maintained is not likely to pose an arc flash hazard.” In NFPA terms, an IR window maintains an “enclosed” state for the switchgear, MCC, Transformer, etc., and maintains energized components and circuit parts in a “guarded” condition. Therefore, the hazard/risk category would be equal to that of reading a panel meter, using a visual inspection pane for lockout/tagout confirmations, or walking past enclosed, energized equipment. • Use of IR windows or “sightglasses” would eliminate the need for a supporting cast of electricians to remove and reinstall panel covers. Those critical personnel would then be available to perform other tasks which were often being outsourced. • Use of infrared windows would provide an efficient method to perform inspections. This would make more frequent inspections feasible for critical or suspect applications to ensure plant uptime. • Use of IR windows would provide non-intrusive access to electrical applications; therefore, surveys could be conducted without elevating risk to plant assets and processes, meaning that inspections could be conducted during peak hours for the best diagnostic data. • Use of IR windows and closed panel inspection would eliminate high-risk tasks during inspections and thereby increase safety for thermographers. The focus of the mill’s initiative was to facilitate inspection Quantity 15 22 27 2 2 2 70 147 197 Table 1 - Equipment List The customer ordered 200 units of assorted 3-inch diameter and 4-inch diameter Infrared Inspection Windows to complete the installation. 197 windows were later installed. Investment 197 infrared inspection windows totaled $42,050.00. IRISS was also retained to supply an installation team to perform the installation of the IR windows. Installation costs sited in Table 2 were calculated using the following assumptions: • Two-man installation team at $625.00 each per day (total cost $1,300 per day) x 10 Days = $13,000.00 • $30.00 per window installation charge x 197 Windows = $5,910.00 december/january 2009 24
For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.