What is your Target Flow?

Replies to This Discussion

Permalink Reply by Greg Wyant on April 8, 2008 at 11:57am

Bob
What type of flow meter did you use??

Permalink Reply by Bob Shovald on April 8, 2008 at 1:32pm

We use the Akron flow meter kit #9301. But you could also use a pitot gauge.
For 180 gpm from a 7/8" tip you need 64psi at your pitot.
Bob

Permalink Reply by William Anderson on May 16, 2008 at 8:24pm

We currently use the Elkhart Chief fixed gallonage nozzles for our 1 3/4" crosslays and skid load. These nozzles are 200 GPM and we (my shift) pump them as 200 GPM nozzles. These are also low pressure fog nozzles that flow the 200 GPM at 50 psi. Depending on the particular hydraulic calculations you were taught, friction loss per 100 feet of 1 3/4" hose could be anywhere from 50-62 lbs. per 100 feet. Hope this helps, its a very hot topic in my department too, I'm just trying to spread the good word of using your equipment the way its supposed to be used and not cheating ourselves out of water.

Permalink Reply by Matt Peksa on May 17, 2008 at 8:12pm

The real question is has anyone out there done any tests with that nozzle using a flow meter. That way you would be able to tell how many GPM's you are flowing at a certain pressure. Like you said there are numerous calculations. Also do not forget how many bends are in the hose will also increase the friction loss. It will always be a hot topic, to bad we all could not have built in flow meters.

Permalink Reply by Ron Burkhardt Jr on June 13, 2008 at 2:26pm

In my company we utilize 2 different nozzle tips on two different size lines. Our primary attack line is 200' of preconnected 1 3/4 with a 15/16 strait tip. Our big line is 200' of 2.5 with an 1 1/8 strait tip. On the 15/16 we achieve 184gpm at 130psi pump pressure. Now the 2.5 we achieve 266gpm at 50 psi pump pressure. These are our target flows and work extremely well for us. They were all pitot gauged before we place them in service. Also we are currently the only co in my town utilizing strait tip nozzles. The 2.5 concept as well as the smooth bore is starting to come into play with some of the other companys. One way we are selling this concept is at multi unit drills in my dept. We stretch two lines one with a strait tip and one with an auto and show people the difference in the streams,amount of nozzle reaction, and school them on the difference in gpm vs psi on both. Also we are about to start training members on using a 2.5 as a primary attack line. Another way I opened some peoples eyes is by going on TFT's website and downloading their flow charts. They show you pump pressure and gpm it really is intersting to see what you think you are flowing and to know what you really are. Three other co;s in my dept use TFT nozzles all the way around from 2.5 down to 1" and we found our Dept Sog on pump pressures to be way off. While they were p****** in the wind we were flowing some serious gpm's. You have an uphill battle ahead of you sound like your higher up's are stuck in the 1980's. Good luck be Safe. Ronnie

Permalink Reply by Shane Furuta on June 13, 2008 at 10:23pm

Thanks Ronnie... You pretty much hit the nail on the head. I have quite a battle ahead of me. I've been starting by teaching the guys around me. Eventually, they'll get promoted and have their own company. Before you know it, everybody is a believer! I know, it's wishful thinking, but I gotta start somewhere. Wish me luck!

Aloha- Shane

Permalink Reply by Anthony Avillo on June 14, 2008 at 7:01am

i'm with ray mcormack
keep it simple
in north hudson, we use 150 for 1-3/4" andf 250 for 2-1/2"

Permalink Reply by Shane Furuta on June 14, 2008 at 2:05pm

Thanks Chief... I try to keep it simple with my crew too (180 gpm for our 1-3/4" hoseline). Problem here is our guys are keeping it really simple by flowing 100 gpm all the time. The real problem is that no one (management and a lot of our company officers) really bother to keep up with what's going on tactically. They feel anything beyond 100 gpm will be "too much to handle". It is very difficult to change our "culture". The Chiefs set the standard, the officers teach and influence the firefighters, bottom line, everyone believes that it is acceptable to fight a structure fire with a hoseline flowing 100 gpm. It's an uphill battle, but I don't plan on throwing in the towel.

Aloha -Shane

Permalink Reply by Adam Kaelin on July 26, 2008 at 10:25am

If potential water damage is a reason given for the low flow, you can use this. (Taken from "Critical Flow Rate by C Bruce Edwards, Fire Engineering Sept 1992 and tests by the Joint Fire Research Organisation in England)

1 gal water absorbs 8,000btus/min
Consider a fully involved 8' high x 20' wide x 25' long office or living room (500 sq ft). The rate of flow to equal the heat output is 160gpm.
Flowing 167gpm the fire will darken down in approx 30seconds, using approx 80 gallons of water
Flowing 250gpm, the fire will darken down in approx 4 seconds, using approx 17 gallons of water

I know the numbers are different but the idea is the same, using the knockout blow in the beginning uses less water overall then using a lower flow for longer.

If I can scan the copy of the article I have I will send it to you.

Permalink Reply by Tim Sitz on July 31, 2008 at 9:27am

Oh brother, does that sound familer, we went throught the same problem 3 yrs ago. We were using TFT automatic nozzles that were bought between 88-94, little to no maintance was ever done to them. Our flows for an 1 3/4" was suppose to be 125 gpm, no one really remembers where the number came from but all handline were suppose to be pumped at 150 psi. with the thought that if we needed more water we could just have the FEO up the pressure (my opion that is a whole other problem). Alot of the springs in the nozzles, since little to no maintance, were stuck flowing 65-95 gpm. Even our 2 1/2" had a TFT on it with a preset pressure of 150 psi.

Luckly I am a huge fan of Andy Fredricks and his opion about attack lines (if you have never read any of his articles I highly recommand that you do they are outstanding and are great ammo when trying to change mentality). I was able to get a class at 05 FDIC Engine Co. Ops/Handline Flows/Nozzles and brought what I had learned there back to my Dept. Set up the same system as at FDIC to prove that we were not flowing the 125 gpm with the TFT and what the nozzle reaction force is at the proper pressure, We used our TFT's an Elkhart 50/150, and a 7/8" smooth bore. After going through the test with all 3 shifts everyone agreed that we needed new nozzles and to up date our mentality on flows.

We went with the Elkhart Chief 50 psi for 150 gpm combo. Some of us tried pushing for the smooth bores but since smooth bores come from "NEW YORK CITY AND THIS AINT NEW YORK CITY" (yea just like in the salsa commercial lol) we lost that fight for the 1 3/4". Thankfully we were able to get a smooth bore on the 2 1/2", we use what Elkhart calls the St.Louis Stack 1 1/8" and a 1 1/4" stack tip, we can now start our flow with it at 250 gpm.

So in closing our flows for 1 3/4" is 150 gpm and our flows for the 2 1/2" is 250 gpm. I hope this little ramble helps.

Permalink Reply by Eric Hankins on August 17, 2008 at 8:27pm

Brother,

As you have read, there is a ton of positive info regarding higher flows. So to keep it simple and add fuel to you fire My department runs

200' 1 3/4" with Akron fog nozzles flowing 170-190gpm
our 2 1/2" runs between 250 and 300gpm depending on nozzle selection

Permalink Reply by Bob Franklin on August 24, 2008 at 10:36pm

I agree with alot of the information presented. My department did a two year study on hose and nozzles. First we researched the FE archives on the original purpose that 1-3/4 was developed as well as the nozzles flows that were produced. We then using flow meters and in-line gauges conducted our own test. We were currently using Elkhart SM 20 automatic nozzles on all our apparatus. Boy were we suprised by the number we got on flows. We used a PDP of 120 through 200 feet of 1-3/4. We found our streams were from 68 gpm to 136, yet the streams all looked alike.

We tested Akron, TFT and Elkhart nozzles. Our nozzle of choice was the Elkhart Chief 4000-14 with a 15/16 built in smoothbore and a 150 at 50 stem in the fog tip. Our target flow is 150 to 165 with the fog. Remove the fog tip and the achieved flow was 180 to 200 depending on pump discharge pressure. The 150 gpm at 50 nozzles pressure has little nozzle reaction and is excellant for interior attack. If the fog stops up with debris. Shut off the beal, remove the fog tip and now you have a 15/16 smoothbore. Two nozzles in one!

Hope this helps, take care be safe,

Bob Franklin

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