Boiler Safety Valves: Practical Guidelines for Maintenance Planning Jim Domitrovich Territory Manager Consolidated ® Pressure Relief Valves August, 2008 Harrisburg, PA

1 Evolution of Boiler Technology On-going boiler enhancements have enabled safe and efficient use of boilers in power generation Development of the safety valve promoted boiler evolution Valve advancements increased control to reduce risk Most important safety device on a boiler or pressure vessel Last line of defense in overpressure situations Protects employees, equipment and environment

2 The Role of Dresser Consolidated 130+ year history with pressure relief solutions for the power generation industry Expertise and application knowledge Commitment to safe, efficient boiler operation Address unique challenges from any application Support from initial design phase through long-term maintenance programs utilizing our GTC Network Elevating valve performance by elevating the level of customer care

3 Safety Valve Maintenance Critical to safe and efficient boiler operation Decreases cost of ownership Development of a safety valve maintenance program can be a challenge Varied operating conditions Physical location of valve within plant/boiler Determination of operating gap Materials used for stack piping, drip pans, condensate drains, etc.

4 Safety Valve Maintenance How often should I inspect or repair my safety valves? Repair intervals for boiler safety valves should be... “determined by operating experience.” The National Board Inspection Code Section RB-8410 At the user level, this statement can be hard to define without knowledge of numerous operating factors.

5 An innovative solution from an industry expert  Safety valve maintenance tool  Interactive CD  Created for boiler applications  Template for developing in-house maintenance programs  Evidence-based approach  Defines “factors” that must be considered  Based on real-life condition  Predicts an estimated repair / maintenance interval

6 Estimated Repair Interval Contributing factors for safety valve condition identified Each factor assigned a weight Based on operational knowledge and actual repair experience Select factor from drop down list Example: Operating Gap Continue to populate factors

7 Competitive Comparisons Total combined factor weight populates automatically For this application, factor weight is 48 Click on “Estimate Repair Interval”

8 Estimated Repair Interval For this valve, the estimated repair interval is approx. 14 months Reasonable estimate for repair intervals of boiler safety valves Based on real life factors that define the National Board ’ s reference to “ determined by operating experience ”

9 Safety Valve Failure A number of factors can contribute to safety valve failure Not opening at set point Not achieving full lift Not closing after reaching blow-down value (Hang-Up) Valve leakage Not opening at all (Worst scenario) Planning a maintenance program using the CD tool can help avoid these failure factors

10 Conclusion Benefits of planning for inspection, maintenance and repair Identification of operational trends Improves access to critical valve data (Valvkeep) Assists in trouble-shooting Manages repair process workflow Provides details for compliance reports Helps prevent costly valve failures

11 Conclusion Any questions?