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Why? A Question for All Inspectors

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http://www.nationalboard.org/Index.aspx?pageID=164&ID=201

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30/12/2016 21:15

Why? A Question for All Inspectors

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http://www.nationalboard.org/Index.aspx?pageID=164&ID=201

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30/12/2016 21:15

Why? A Question for All Inspectors

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http://www.nationalboard.org/Index.aspx?pageID=164&ID=201

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Why? A Question for All Inspectors Lee Doran National Board Consultant Fall 1993 Category: Operations Summary: The following article is a part of National Board Classic Series and it was published in the National Board BULLETIN. (3 printed pages) "Why?" is the question that is always on the mind of the curious boiler inspector. The inspector, whether from the jurisdiction, insurance company or the operator/maintainer, must always ask this question. The inspector's job is not finished when corrective action is recommended to correct an obvious problem discovered during an inspection; there is more. The inspector must ask, "Why did this happen?" Review the following hypothetical situation as an example. An inspector discovers cracks in the fireside of a mud-leg in a firebox-type steam boiler and recommends a repair by welding. In this case, if the question, "Why did the plate crack?" is not asked, only the symptom is corrected and the cause of the problem is not detected. If the question is asked, further investigation may reveal that the mud-legs are packed with scale, insulating the plate from boiler water. Of course it would be required that the boiler be cleaned of scale before the weld repairs are made. If a second question, "Why is there scale?" is not addressed, then another symptom would be corrected without affecting the root of the problem. When the cause of the scaling is investigated, it would most likely be discovered that the boiler is using excessive make-up water. Again, why? After pressing further, the investigation reveals that the condensate return pipe is leaking. It would be recommended that the leaking pipe be replaced. The investigation continues, only to uncover that the pipe leaked because of internal corrosion. It is now recommended that the services of a water treatment specialist be acquired. The specialist determines the boiler water requires treatment not only for preventing scale in the boiler, but also treatment of the condensate and pre-boilers systems to inhibit corrosion. The inspector recommends that the boiler water treatment program be closely monitored and adjusted as necessary. If the inspector had stopped asking, "Why?" at any point during the investigation, only the symptoms would have been corrected and the problems would be recurring. Inspections routinely evolve into investigations with symptoms of a problem providing the clues to the inspector. Only by asking, "Why?" at each step of the investigation will the inspector identify the root cause of the problem and be able to recommend the proper and complete corrective action. Editor's note: Some ASME Boiler and Pressure Vessel Code requirements may have changed because of advances in material technology and/or actual experience. The reader is cautioned to refer to the latest edition and addenda of the ASME Boiler and Pressure Vessel Code for current requirements.

30/12/2016 21:15

Why? A Question for All Inspectors

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http://www.nationalboard.org/Index.aspx?pageID=164&ID=201

A Boiler: The Explosive Potential of a Bomb Acoustic Emission Examination of Metal Pressure Vessels Anatomy of a Catastrophic Boiler Accident Austenitic Stainless Steel Auto-Refrigeration Basic Weld Inspection - Part 1 Basic Weld Inspection - Part 2 Black Liquor Recovery Boilers - An Introduction Boiler Efficiency and Steam Quality: The Challenge of Creating Quality Steam Using Existing Boiler Efficiencies Boiler Logs Can Reduce Accidents Boiler/Burner Combustion Air Supply Requirements and Maintenance Carbon Monoxide Poisoning Preventable With Complete Inspection Combustion Air Requirements:The Forgotten Element In Boiler Rooms Creep and Creep Failures Description of Construction and Inspection Procedure for Steam Locomotive and Fire Tube Boilers Ensuring Safe Operation Of Vessels With Quick-Opening Closures Environmental Heat Exchangers Factors Affecting Inservice Cracking of Weld Zone in Corrosive Service Failure Avoidance in Welded Fabrication Finite Element Analysis of Pressure Vessels Fuel Ash Corrosion Fuel Firing Apparatus - Natural Gas Grain Boundaries Heat Treatment - What Is It? How to Destroy a Boiler -- Part 1 How to Destroy a Boiler -- Part 2 How to Destroy a Boiler -- Part 3 Identifying Pressure Vessel Nozzle Problems Inspection, Repair, and Alteration of Yankee Dryers Inspection, What Better Place to Begin Laminations Led to Incident Lay-up of Heating Boilers Liquid Penetrant Examination Low Voltage Short Circuiting-GMAW Low Water Cut-Off Technology Low-Water Cutoff: A Maintenance Must Magnetic Particle Examination

30/12/2016 21:15

Why? A Question for All Inspectors

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http://www.nationalboard.org/Index.aspx?pageID=164&ID=201

Maintaining Proper Boiler Inspections Through Proper Relationships Microstructural Degradation Miracle Fluid? Organizing A Vessel, Tank, and Piping Inspection Program Paper Machine Failure Investigation: Inspection Requirements Should Be Changed For Dryer Can Pipe Support Performance as It Applies to Power Plant Safety and Reliability Polymer Use for Boilers and Pressure Vessels Pressure Vessel Fatigue Pressure Vessels: Analyzing Change Preventing Corrosion Under Insulation Preventing Steam/Condensate System Accidents Proper Boiler Care Makes Good Business Sense:Safety Precautions for Drycleaning Businesses Putting a Stop to Steam Kettle Failure Quick Actuating Closures Quick-Actuating Door Failures Real-Time Radioscopic Examination Recommendations For A Safe Boiler Room Recovering Boiler Systems After A Flood Rendering Plants Require Safety Repair or Alteration of Pressure Vessels Residential Water Heater Safety School Boiler Maintenance Programs: How Safe Are The Children? Secondary Low-Water Fuel Cutoff Probe: Is It as Safe as You Think? Short-Term High Temperature Failures Specification of Rupture Disk Burst Pressure Steam Traps Affect Boiler Plant Efficiency Steps to Safety: Guide for Restarting Boilers after Summer Lay-Up Stress Corrosion Cracking of Steel in Liquefied Ammonia Service - A Recapitulation Suggested Daily Boiler Log Program Suggested Maintenance Log Program System Design, Specifications, Operation, and Inspection of Deaerators Tack Welding Temperature And Pressure Relief Valves Often Overlooked Temperature Considerations for Pressure Relief Valve Application

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Why? A Question for All Inspectors

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http://www.nationalboard.org/Index.aspx?pageID=164&ID=201

The Authorized Inspector s Responsibility for Dimensional Inspection The Effects of Erosion-Corrosion on Power Plant Piping The Forgotten Boiler That Suddenly Isn't The Trend of Boiler/Pressure Vessel Incidents: On the Decline? The Use of Pressure Vessels for Human Occupancy in Clinical Hyberbaric Medicine Thermally Induced Stress Cycling (Thermal Shock) in Firetube Boilers Top Ten Boiler and Combustion Safety Issues to Avoid Typical Improper Repairs of Safety Valves Wasted Superheat Converted to Hot, Sanitary Water Water Maintenance Essential to Prevent Boiler Scaling Water Still Flashes to Steam at 212 Welding Consideration for Pressure Relief Valves Welding Symbols: A Useful System or Undecipherable Hieroglyphics? What Should You Do Before Starting Boilers After Summer Lay-Up? Why? A Question for All Inspectors

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30/12/2016 21:15