FURNANCE EXPLOSIONS
Recent furnace explosions serve as a reminder that boilers must
be maintained and operated in strict compliance with the manufacturers'
recommendations. A furnace explosion is usually the result
of ignition and instantaneous combustion of highly flammable
gas, vapor, or dust that has accumulated in a boiler. The
effect of the force from the explosion is often much greater than
the boiler combustion chamber can withstand.
Minor
explosions, commonly know as deflagration, puffs, flarebacks,
or blowbacks, may suddenly blow flames from firing doors
and observation ports. Anyone in the path of a flame, which might
extend many feet, may be seriously burned. An increase
in the
intensity of the explosion would naturally increase the
probability of a serious accident.
Furnace
explosions may be avoided by taking reasonable precautions:
- Ensure
that fuel inlet valves on nonoperating burners and ignitors
are tightly closed and do not leak.
- Purge
the furnace in accordance with the manufacturer's
specifications each time before the first burner is ignited.
- Ensure
that the ignitors, fuel regulating controls, and flame
safeguards operate as required.
- Ensure
that the fuel/air ratio is in accordance with the
manufacturer's specifications.
- Remove
oil guns from idle burners after closing the oil and
air or steam supply valves when shutting down oil burners. Drain
and clean residual oil from the guns before storage.
- Never
use the boiler's soot blowers to blow soot in a cold
boiler.
- Ensure
that limit and operating controls are in good working condition
and are not "by-passed" or "jumpered-out."
Proper
operation, proper maintenance, and timely inspection are
key elements in ensuring safe boiler operation. For more information
contact the North Carolina Department of Labor, Boiler Safety
Bureau. |
