AIS Forensic Engineering AIS Forensic Engineering    Forensic Engineering - Forensic Testing Laboratory

Here are some cases on: Chimney Fire, Flash Fire, Water Hammer, How To Repair Cast Iron, Tank Explodes, Boiler Low Water, Chemical Plant Fire.


The below forensic investigations are from a few of the closed case files. Client names are protected as well as the individuals involved to protect their rights to privacy as well as in those unfortunate accidents where life long disabilities persist for the injured or worse where fatalities were involved.

Steam Condensate Water Hammer in Pipes

The +2-mile steam tunnel steam piping supports had been slowly wasted away and one of the branch steam pipes to a building mechanical room allowed the steam pipe to become partially self-supporting causes water hammer in steam pipes: consequentially, the steam pipe line sagged ½-pipe diameter in a long pipe run or branch in a crawl space. At the lowest steam piping section the steam pipe line collected steam condensate in the steam pipe. When the mechanic brought the building heat on-line the condensate laying in the steam pipe was entrained with the steam going into the building where the operator was. A large heavy cast fitting that redirected the steam 90-degrees ruptured from the steam condensate water hammer. The steam boiler operator was several feet away when the steam explosion occurred and could not exit the mechanical room fast enough. The steam boiler operator was fatally injured. To prevent water hammer in steam pipes and water hammering in pipes maintenance and repairs were needed. Water hammering in pipes had been experienced for sometime. ( water hammer pipe )

Metallurgy of Brittle Steadite: Steam Condensate Water Hammer Explosion Accident Pipe and Flange: Steam Condensate Water Hammer Explosion Accident Damage investigated by forensic engineer and expert in steam condensate explosions

Boiler Steam Explosion: Boiler Low Water and Low Water Cut Off

A firetube scotch marine boiler (FTSM) at 200-psi was destroyed by a steam explosion (rapid phase transition explosion) which occurred as a result of a boiler low water condition when the low water cut off controls ( low water cut out ) and safety devices failed. 

  • The steam explosion (rapid phase transition explosion) resulted from instant flash of boiler feed water on the white-hot furnace corrugated tube
  • A steam explosion provided the necessary force that propelled the 30-ton boiler body forward suddenly such that the piping connected to the boiler sheared including the safety valves and the boiler propelled by steam thrusting the boiler forward 77 feet through concert wall, and moving several 2-ton bolted down machines. The six-ton rear door was thrown over 300 feet in the opposite direction
  • The boiler low water condition had three low water cut off also known as low water cut out.
FTSM Boiler steam explosion at corrugated furnace tearing weld Boiler steam explosion showing rear tube sheet that ruptured and severily overheated

Chemical Plant Explosion - Pressure Vessel Tank: Tank Explodes

Chemical plant explosion was caused by the thinning of a pressure vessel tank internal -compartment- head that collapsed & buckled. Tank explodes because the integrity of the welds diminished and thinning of the head were overloaded casuing the chemical plant explosion.

Forensic engineer and pressure vessel expert investigated internal explosion of storage pressure vessel micrograph of toe of weld that intiated explosion - accident investigated by forensic engineer

Chemical Plant Fire from hot oil auto-ignition of LDPE Plastic to Flash Fire

Large chemical plant fire from scaffolding being moved damaging a pipe. The damage was large enough to spray hot oil on a piece of LDPE plastic sheeting and auto-igniting creating a flash fire in the heart of the chemical plant. The workers had to use at approximately 25-lbf to push the wheeled scaffolding that casued the chemcial plant fire.

Fire ball damage pipe rack during asbestos abatement investigated by forensic engineer FEA of piping done by forensic engineer on hot oil transfer line that cause oil to spray and auto ignite causing fire ball in chemical plant

Hot Water Heating Boiler - Cast Iron Boiler Expansion Tank Fails and How to Repair Cast Iron

A newly installed hot water heating boiler had cracked the installer showed owner how to repair cast iron, but instead caused scalding or burn related injury to owner when the hot water boiler was brought up to operating temperature where the relief valve lifted and directed scalding hot water on the home owner causing permanent injury. The injury resulted because the discharge pipe was not piped to a safe point and the safety valve lifted because the expansion tank had a leak causing the air cushion to be lost and vented away. How to fix cast iron boilers is not to repair cast iron.

hot water boiler relief valve opens and scalds owner during initial start-up Boiler expert finds expansion tank was tested and found to have lost charge causing the RV to open spraying scalding hot water on owner

HTHW (Hot Water) Piping Explosion - Water Hammer Flash to Steam Condensate

HTHW highigh pressure piping exploded from a hydraluic water hammer with resulting steam and condensate exploding outward and failure analysis was done by expert in steam condensate water hammer explosionsHTHW (high temperature hot water) high-pressure piping system installed in the1960's ruptures from anoperational hydraluic 'bump' from the campus physical plant.

The campus heavy duty piping was found to have many localized corroded manhole and pipe. High water table and poor drainage from rain and snow melt caused corrosion. The corrosion protection system installed in the 1960s was depleted after many decades and their location was not documented.

Thining of the piping was reached danagerous levels and failures occured.

What is a hot water boiler: HTHW is a High-Temp Hot Water Boiler - Generator, MTHW Boiler (Generator) is a Medium Temperature Boiler or Generator and a hot water boiler is considered a LTHW Boiler or Generator.

Roof Fire with Chimney Flue: Boiler Oil Burner

Boiler chimney flue was installed in building a decade and a half before the chimney flue thimble eventually caused the roof fire. Testing, examination and reconstruction proved the chimney flue construction method used was poor, for the factory built chimney flue was assembled incorrectly and chimney flue leaked hot chimney flue gases on roof combustibles. Under a specific atmospheric and building draft conditions the roof auto ignited setting the large building roof on fire. ( Chimney fire )

Boiler and furnace expert testing in laboratory the flow and pressure characteristics of chimney flue piping Boiler expert logging manometer readings from flow and pressure tests on a college boiler flue piping to damaged campus main building roof College chimney wooden roof showing fire damage

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