Snap-tite Hose received notice of a catastrophic failure of a 5 way manifold in New Jersey thru their dealer. Following are some points of note from the email accounts they received. (See entire report info below)
1. A loud noise 'like a freight train' was heard before the failure occurred.
2. The gauge on the manifold did not register an increase in pressure (this was mentioned several times).
3. The local water company notified fire department personnel that they had 'high pressure on the hydrant' requiring manual control of the pressure at the pump station.
4. The relief valve on the manifold did not relieve.
The fire department also submitted several photos of the failed appliance which are posted.
Snap-tite's history with these units is very good. They are rarely returned for warranty repairs and there have been no warranty catastrophic failures.
CONCLUSION:
It is apparent from the evidence provided that the cause of this failure was a severe over-pressure condition, such as water hammer. Fire Department personnel state that they were careful not to create any conditions that might result in water hammer. The actions of the water authority should be closely examined as they did admit that they had caused an overpressure in the system. Improper operation of a valve in their system could have set up a water hammer condition which traveled through the hydrant and to the manifold.
RECOMMENDATIONS:
1. Water hammer is an extremely destructive force and must be prevented at all costs.
2. Due to the significant damage caused to this appliance, Snap-tite Hose highly recommends a thorough inspection of other components which may have been subjected to this pressure
Attempting to compress the relief cartridge in a vise to loosen the corrosion.
spike. This would include other appliances, hoses, connectors, adapters, and perhaps truck piping and pumps.
3. Relief valve maintenance is critical to the safety of personnel and equipment. The guidelines for appliance maintenance and testing as established in NFPA 1962 are highly recommended. We recommend that all relief valves be immediately tested for proper operation, and that a schedule be created and maintained.
4. All appliances should be service tested annually as recommended by NFPA 1962.
NOTE: The ENTIRE REPORT from Snap-Tite is on our home page, under NEWS/UPDATES.
Please check it all out for the entire document. Thanks for their sharing of this information.
And lastly, thanks for your kindness on behalf of Gordon and I regarding the earlier TSL.
Take Care-BE CAREFUL.
FROM FDIC....
BillyG
The Secret List 4-20-09 / 2230 hours
www.FireFighterCloseCalls.com
