Hydraulic Firesgreenspun.com : LUSENET : Elevator Problem Discussion : One Thread
Are oil based hydraulic systems a fire hazard. Has anyone had experience of Fires starting in Lift Hydraulic systems. We are doing risk assesments and we are looking at replacing hydraulic oil with a fire resistant fluid. Does anyone have any experience
-- Susan Bray (email@example.com), July 26, 2004
Hydraulic oil, is fire resistance and you do not have to replace it with any thing.
-- (firstname.lastname@example.org), July 26, 2004.
Hi There, I think the flash rate of hydro oil is quite high, the real hazzard is rags and floor sweep left on job. They are like a wick in a candle and should be removed from any pits and hoistways cleaned of any fuss from bldg,linen,dust,that can be flamable. I have seen fires in pits climb right up rails in hoistways. Water hydros are 99.% water and will not be a problem but you cant substitute, you need older special pump and valve. You should have fire detection equip in the pit and you should be ok. Give your union elevator company a few bucks for hoistway cleaning.
-- Jim (email@example.com), July 26, 2004.
Susan, The flash point of most hydrauilic oil is +/- 400 degrees F. Normal hydraulic elevator operating temp. is between 90 and 125 degrees F.
As you can see this is well below the flash point. The flash point being the point at witch the oil will ignite if exposed to a flame/ignition source.
I think your concerns might br better served from a sepage point of view. Is your system protected from leaking oil into the ground? If not you might consider a synthetic vegtable oil. Otherwise I would not be overly concerned. Check the MSDA reports of the oil you are using verses the oil you are considering. Sounds like money that need not be spent.
-- Elevator fella (Fire@hotmail.com), July 28, 2004.
Hydraulic fluid alone is not a fire hazard, however as stated above, oily rags etc are. In other words the real fire hazard is poor housekeeping.
-- Mike (firstname.lastname@example.org), July 31, 2004.
Has anyone experienced a situation with the submersible hydraulic pump and motor failing to shut off causing the oil in the tank to reach the point that it begins to smoke. Recently had this happen in a nursing home and was wondering how close to ignition we might have been.
-- John Chevalier (email@example.com), August 29, 2004.
Just tonight we had a submersible hydraulic motor stick ON and heated up the oil in the resevour which set off the smoke detector above it, which called the Fire Dept. The smoke gradually subsided and was quickly exhausted by the dedicated exhaust fan. With infrared thermometer, the oil temp was 250deg and dropping about a degree per minute. If that rate of decline was consistent, the oil was approx 350degF when we manually shut off the elevator pump. How close to catch fire were we? I'm amazed there wasn't some safety device on the elevator for shutting down an overtemp situation. Thank goodness for the smoke detector and panel and dialer.
-- Steve Roberts (firstname.lastname@example.org), October 25, 2004.
I am surprised that there is not a themistor or thermocouple shutoff on your oil tank.
All of our jobs are so fitted.
-- Richard (email@example.com), November 03, 2004.
If the motor starter uses a conventional contactor, the contact can become welded in the on position. When that happens, temperature sensors can't do anything to shut the motor off. Since the pump is simply bypassing oil throughte control valve, the motor current is not high enough to trip the motor circuit breaker. How should these conditions be handled? Currently, there is no protection against this, unless it's using a soft starter with built- in redundancy.
-- drew (firstname.lastname@example.org), March 03, 2005.