I am intrested in hearing what people think about 2" hose especially the users and the ones who are against it. Give me some pros and cons. I personally like it for high rise and big hit handlines. The stuff is alot easier to deploy than 2-1/2" and can flow 400gpm with no problem.
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Thread: two inch hose
03-07-2000, 08:45 PM #1BIG PAULIEFirehouse.com Guest
two inch hose
03-07-2000, 09:51 PM #2Batt #2Firehouse.com Guest
Big Paul I got you book laying the big lines at FDIC. It is the best book on LDH I have ever read. 3/4 of the book I have read and like every thing you wrote. good job
03-07-2000, 11:24 PM #3resqcaptFirehouse.com Guest
What kind of engine pressure would be needed to get 400 g.p.m. from a 2" hoseline? We're currently exploring going back to 2 1/2" for attack lines and standpipe ops. from our current 3" The 3" would still be kept for skid load, portable deck guns, etc.
We have been toying with also evaluating 2". One major thing we have to keep in mind is available pressures in our standpipes so we are trying to get as much flow with available pressure.
"RESCUE"-The firefighters that firefighters call!
03-08-2000, 10:02 AM #4BIG PAULIEFirehouse.com Guest
Steve, Here is the way I got 400 gpm. Using 200' of 2" 400 service presure hose with a 1-3/8" tip @ 52 psi nozzle pressure at 244 engine pressure. With a 1-1/4" tip or a master stream automatic at 80 psi nozzle pressure with an engine pressure of 272 psi. This is a big hit line not an advancing line while flowing water.
03-08-2000, 01:43 PM #5FIRE549Firehouse.com Guest
Hey Big Paulie, what is your opinion on using 3" hose as a tactical handline?
03-08-2000, 01:59 PM #6chiefjay4Firehouse.com Guest
we run 1-2" line, with a 1" tip....pulled it last week on a commercial fire but didn't flow it. In drill it flows nice though. Anyway it's coming off next fire first line....i'll let you know
03-08-2000, 02:17 PM #7S. CookFirehouse.com Guest
We like 2" attack line with an SM30. I'll generally call for the 2" when we pull up with heavy fire showing on ~1500 sq. ft. or so structure gives a pretty big hit. If we need something larger, we go with a Big Paulie from a 2.5" or 3" line.
With just smoke, light fire, or smaller frame structures we go with the 1.75" lines with SM30s
[This message has been edited by S. Cook (edited March 08, 2000).]
03-08-2000, 07:28 PM #8BIG PAULIEFirehouse.com Guest
To fire 549, In my opinion a 3" handline makes an exelent big hit Blitz line. It can move the water safely (up to 600 gpm) and can be easily deployed by two firefighters. 3" actually has a better nozzle reaction absorbing capability than a 2-1/2" because of the increase in hose surface on the ground. Can a 3" be advanced easily? Hell no. It's just for the initial big hit on a large fire. I would rather use a 2-1/2" for the same purpose but if 3" is what you have than by all means use it.
03-08-2000, 07:39 PM #9FIRE549Firehouse.com Guest
Thanks for your input. A couple of our apparatus have 3" hose in the bed and we may consider using it as a "Blitz attack line".
By the way can you advise on the limitations on the length of a 5" supply line laid from a 1500gpm hydrant into a pumper? How long of a supply line is viable in this situation when 1,500gpm is needed on the fireground?
[This message has been edited by FIRE549 (edited March 08, 2000).]
03-09-2000, 11:04 AM #10FyredUpFirehouse.com Guest
We use 2 inch attack lines. The nozzle choice is a 200 gpm at 75 psi low pressure break-a-part nozzle backed with a 1 1/4" smooth bore.
Our FF's like this setup and there has been no complaint about weight or any other problems.
03-09-2000, 11:30 AM #11resqcaptFirehouse.com Guest
Thanks for the info. I'll have to try that when we start evaluating hose.
Next question. I've read and seen people using a flow meter on the intake side of the pumper to guage flow. Is this the best method for determining flow from a handline? It seems that it would work great. Let me know what you think.
"RESCUE"-The firefighters that firefighters call!
03-09-2000, 08:50 PM #12Lieutenant GonzoFirehouse.com Guest
Our Engines carry a 200' preconnect of 2" attack line with an SM30F combination nozzle. for structure fires, this is the line that I prefer, for its gpm and knockdown power.
Take care and stay safe...Lt. Gonzo
03-10-2000, 12:51 PM #13STATION2Firehouse.com Guest
We have preconnects of the following size and length:
2-200'of 2.0" (1 With a Vindicator VBA)
1-100'of 3.0" w/200'of 2.0"
1-200'of 2.5" (With a Vindicator VBA)
If on arrival there is alot of fire showing, we will pull a 2" line first. Usually a 2" w/a Vindicator nozzle is the one pulled. This allows us a great knockdown capability with superior GPM to knock it. Our 200'of 2.0" w/a Vindicator VBA will flow 320 GPM. We pump 190 PSI at the panel and that gives us 45 PSI nozzle pressure. The same line w/a 1" Smooth bore tip only flows 210 GPM. A 1-1/8" tip on the same line will only flow 235 GPM. This above setup works great for us. Be safe.
03-10-2000, 01:09 PM #14STBURNEFirehouse.com Guest
I was taught to not exceed 250 psi on an attack line. The reason for this was because the velocity of a burst line above this pressure was enough to kill or seriously injure a firefighter. Sure the hose we use has burst pressures of 400-600 psi, but these numbers come from manufacturers who test their brand new, unused hose in a controlled environment. Was this hose dragged across glass, nails, jagged metal, exposed to severe heat conditions, hazmat, and all the other fireground conditions in the real world we work in?
Also, what about the rule of thumb to not exceed tip diameter on the nozzle by more than half the hose size? Any problems with a 1 1/4" tip on a 2" line?
2" is good, but it isn't a duece and a half.
03-10-2000, 05:13 PM #15KEAFirehouse.com Guest
>Also, what about the rule of thumb to not exceed tip diameter on the nozzle by more than half the hose size?>
Great Question. Ask this one next time someone tells you that: Says Who?
The best information that I have been able to gather on this subject are peoples opinions with no testing to back it up. No problem!
Our testing has shown that you can in fact use a larger tip size such as a 1 1/4" tip on a 2" line like you mentioned. The key is the design of the Smooth bore and wether you "Think" the stream looks good.
The primary reason this rule of thumb has been around is because the FL in the hose gets to a point with the higher flows that it can not be stabalized within the larger smooth bore to give a stream that "looked" as good as a smaller smooth bore. It still flowed the water but looked different.
The solution was to use longer smooth bores(Playpipes). If you take a stuby smooth bore found on some break apart fogs and compare the stream to a normal 5-7 inch long smooth bore of the same size you will find that the longer smooth bore provides a better "Looking" stream.
In the case of the Big Paulie nozzle, this challenge of stream quality versus tip size is overcome by a stream shaper prior to the nozzle. It's simple and it works!
If your going to opt for a 2 1/2 line, ask yourself: What is my target flow for that line? In most cases that answer can usually be supplied by a 2" line properly outfitted and pumped.
First Strike Technologies, Inc.
Note: This post is not intended to promote or degrade any particular product, brand or style of firefighting. It is only intended for those who have minds like parachutes........They work best when there open
03-10-2000, 06:02 PM #16LHS'Firehouse.com Guest
-what about the rule of thumb to not exceed tip diameter on the nozzle by more than half the hose size-
I hope FDNY doesn't read that. They'd have to get rid of all their 15/16" SB's.
a 1" tip would be the limit on a 2" line.
If we convert tip to flow then 135 gpm would be the 1 3/4" hose limit and 210 the 2" limit.
It is kinda like the rule of leave 20 psi on the suction gauge just in case. 20 psi with a 2 1/2" line could be 200 gpm and 1750 gpm with a 5" line. That's a pretty nice spread. Old ideas, new world.
Another long term adage is heat travels thorugh water. That puttig water between the exposure won't work, it has to be put on the exposure. I agree it should be on the exposure, I can't prove the heat passes through a water stream. If it did why don't we get burn on a LP prop?
Just one persons opinion, based upon seeing and doing for 25 years, do't get riled up, all fires go out everywhere even if the FD doesn't show up, if you don't agree with the answer just pretend you didn't read it, apply whatever you think works.
03-10-2000, 08:46 PM #17STBURNEFirehouse.com Guest
The reason we do not get burned on the LP prop is because the fog nozzle is blasting a cone of air towards the burning propane and PUSHING the fire away from us. A good example of why fog streams should not be used inside structures. Fog nozzles should be renamed HAZMAT nozzles.
03-10-2000, 09:58 PM #18BIG PAULIEFirehouse.com Guest
I think the suction side placement of the flow meter will be OK but to be honest with you I am not too familiar with that type of operation. Hey KEA I know you can help here . What do you think. Also maybe contact one of the flow meter MFG
03-10-2000, 10:08 PM #19BIG PAULIEFirehouse.com Guest
I have read about the tip size VS hose size formula in the IFSTA fire streams book. They do not tell you why this formula needs to be followed just like they do not give reasons for alot of there rules. I can personally tell you that I have been able to accomplish alot of what they say can't be done. Follow thwe golden rule. Experiment before you implement and follow the manufacturers rules for there products. Oh yea. PLEASE keep an open mind.There is more than one way to deliver water on the fireground and be sucessful even if it isn't the way some big city departments say it has to be done.
03-10-2000, 10:29 PM #20S. CookFirehouse.com Guest
Regarding the stream shaper on the Big Paulie - it also helps give you some leverage to move the tip around when you need to.
We played with the stack tips from our BP right off the shutoff and with a 5" stream shaper just to see what happens. Both streams were decent, but you didn't have any leverage to move the tip very well if at all (also - we couldn't put the BP handle on either of these setups).
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