To View the Tables Click Here – How to Destroy a Boiler 190509 David Linsell
David Linsell – MSc CEng FIMarEST FIMechE MIPowerE CDipAF – Linsell Engineering
We all know, or should know, the importance of good boiler plant operation and maintenance. Generally, if we do the rights things then all will be well. Most boiler house teams, most of the time will be doing their best to look after their plant, hoping that what they do is good enough. But how can they know?
I often find that turning problems or questions on their head can be a pathway to greater understanding. So instead of focusing on what we should do to look after our boilers, I want to ask the opposite question. What happens when we deliberately imagine how we can destroy our boilers? What would failure look like? What would the pathway to failure look like?
If we can understand how and why failures occur, then we should all be better able to prevent those failures.
Poor management, operation or maintenance of boiler plant and auxiliaries can result in catastrophic failure of boiler plant. Catastrophic failure is characterised by any, or all, of the following:
- Damage to plant and property
- Explosion causing catastrophic damage to plant, and buildings
- Injury or death to operators
- Injury or death to non-operators and/or members of the public
In the case of a boiler explosion, fortunately a rare event, it is usual for the burner to detach and travel away approximately on the axis of the boiler in one direction while the boiler shell travels approximately on the boiler axis in the other direction. The boiler shell may travel many metres, the burner could travel farther; other shrapnel may travel even farther. This prime event may cause other damage, e.g. fracture of fuel lines, further ignition of fuel, damage to building and other plant.
Avoidance of catastrophic failure should be achieved by proper and close attention to correct operating and maintenance practices.
In Table 1 I have imagined and identified 12 scenarios that have the potential to cause catastrophic failure. And I allow for an unlucky and as yet unidentified 13th scenario.
Where events in the Table below do not immediately lead to a catastrophic event, they may still result in:
- Additional maintenance costs and outage time for :
- acid cleaning
- weld repairs
- Reduction in boiler rating capability; the Competent Person reducing the maximum allowable pressure or safe operating limits of the boiler
- Early removal from service following withdrawal of authorisation to operate by the Competent Person.
Boiler Managers and Operators are recommended to study the Table to reinforce the importance of correct operation and the possible consequences of incorrect operation.
