Flex-Fire Sprinkler Heads

[NJ1]

I am not an expert when it comes to design so I would like some opinions and advise when it comes to these types of sprinkler heads.

I am currently bidding in a federal job that states on the fire sprinkler specs the use of flex heads. I question the contractor why such requirement since this could impact the hydraulics and the integrity of the installation.
Questions:
1) How much flex heads can affect the existing hydraulics of the systems by converting from ridgid pipe to flex.
2) In the case where a fire pump is employ why used flex heads. Could this affect the installation and performance of the system?
3) Has anyone seen a flex head come loose from drop ceilings?
4) would you recommend not to use this type of head in applications such as Hospitals, Educational Institutions, Medical Labs, ect.

 

[TravisMack]

1) How much flex heads can affect the existing hydraulics of the systems by converting from ridgid pipe to flex.

These can have a major impact on the system, depending on the lengths used. Some of the off brand flex sprinkler head connections have 50+ equivalent feet to be considered. That could blow a system way over the curve

2) In the case where a fire pump is employ why used flex heads. Could this affect the installation and performance of the system?

We have designed flex heads for use on systems with fire pumps for many years. I have yet to hear of anything affecting the installation and/or performance. At a local Intel plant, flex heads are used all over the place - office ceilings / clean room areas / duct sprinklers / etc...

3) Has anyone seen a flex head come loose from drop ceilings?

I have yet to hear of this happening

4) would you recommend not to use this type of head in applications such as Hospitals, Educational Institutions, Medical Labs, ect.

Again, we have used these in hospitals, schools, office buildings, malls, etc.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

 

[pipesnpumps]

I reviewed a set of plans late this afternoon for a large medical clinic that used aquaflex heads.. This was shop drawings. The AE missed lots of things including a lab with flammable liquids designed as ordinary hazard ( we require OH2) and some other density oopsies. The sprinkler sub missed things like no relief valve (2010 reqt), no forward flow test for bfp I had to check all this against the AE design, check hydraulic calcs etc. Pull out civil dwgs to see if FDC was within 150 ft of a hydrant. Then I had to google search aquaflex to get the page that has their loss calcs, and it was 44 ft of 1".. This NICET is one of the better ones I see sometimes and i wasnt surprised she accounted for this in calcs.. I had 2 hours to review the plans and write up the code basis and required resolution. It saves time with contractor arguing. Got 2 hours and spent 3. Gave 1 hour free. Just wanted to illustrate my earlier point in an example.. Checking the equivalent length required extra effort and is so easy to miss this detail. Especially if I had put pencils down after 2 hours of reviewing and commenting. But it was about a FIVE PSIG difference.. Luckily have a strong water supply.


NJ1 Don't worry about using flexheads. They are accepted everywhere and meet 13.

Real world knowledge doesn't fall out of the sky on a parachute, but rather is gained in small increments during moments of panic or curiosity.

 

[pipesnpumps]

BTW Travis Mack, it is a small world. I've done some design work for that plant. 22 and 32.

Real world knowledge doesn't fall out of the sky on a parachute, but rather is gained in small increments during moments of panic or curiosity.