Thread: 3 INCH vs 5 INCH Hose for supply
10-22-1999, 07:07 AM #1BURNSEMSFirehouse.com Guest
3 INCH vs 5 INCH Hose for supply
After Looking at the answers to my Post on FOWARD vs REVERSE Lay I see agreat deal of differance, Our Dept is Upgradeing our Supply Hose, we only have approx 22 Hydrants in the City and Flow Rates vary from place to place but generaly are at or above 450gpm, I know compared to some thats weak but would 5 Inch still work better than 3 Inch under a Worst Flow Scenario.
Here today for a Safer Tomorrow
10-22-1999, 09:36 AM #2JimDWFDFirehouse.com Guest
Go with the 5" hose. If you want all the water the hydrant will give the LDH will get it to the pump. Friction loss in the 5" is 6psi/100ft(text book) at 1000gpm. The 3" you will need dual lines with 22psi/100ft. It only makes sense to use LDH. Plus it's less hose to have to pick up when your done.
10-22-1999, 09:46 AM #3S. CookFirehouse.com Guest
JimDWFD is right. The 5" will give you more water with less hose down.
According to the manufacturer:
5" Angus hi-vol friction loss at 450gpm is 0.70# per 100', at 1000gpm it's 3.37# per 100'.
Compared to the 3" with 2-1/2" couplings at 450gpm with 10.5# per 100' and 47# at 950gpm.
10-22-1999, 11:49 AM #4Jim M.Firehouse.com Guest
We converted to 4 inch 12 years ago and thought we'd died and gone to heaven. The friction loss (compared to 2 1/2 inch) was negligible, the maintenance was non existant and the volume of water you could flow was amazing. We now are converting to 5 inch for the same reason. Check the books on flow and friction loss. The formulas I learned in high school (about 100 years ago) for the diameter of a circle never had much of an impact until I started looking at the hose size comparisions. Roughly speaking (fireground hydraulics), you can push twice as much water through a 4 inch compared to a 3 inch. Roughly speaking again, you can push twice as much through a 5 inch compared to a 4 inch. Will it help you when theres no water nearby? No, but it's a tremendous help when you DO have the water to move it from one point to another.
10-22-1999, 02:32 PM #5FyredUpFirehouse.com Guest
5 inch hose shines in two situations:
1) When you have all the water in the world and you want to move it to where you are. Low friction loss for large flows in comparison to 2 1/2, 3, or 4 inch hose.
2) When the water supply is limited and you want to get every drop of it to where you are. With a 450 GPM hydrant you want all that water to your engine, at 1000 plus feet 5 inch can do that easily.
Go with the 5 inch you will not be disappointed. We have had it for about 5 years and we have no problems or complaints.
As a side light, we have different colors of 5 inch for our 2 engines equipped with 5 inch. That way there is no question as to where it goes after the fire is out.
10-22-1999, 03:34 PM #6S. CookFirehouse.com Guest
Good points on the colors Fyred Up.
Our engines have 1200 feet of 5" split loaded. 600' of it is yellow, 600' orange. That way you can tell when to change sides of the hose bed when loading, know when half the bed is down on the long lays off one rig and # of feet down on multiple rig lays without counting all the sections (just count the color changes).
To ID which hose goes where, we had Kochek anodize all of our couplings and adapters different colors, one color for each rig.
10-22-1999, 03:41 PM #7Todd TrimbleFirehouse.com Guest
Keep in mind, there's no free lunch. (Note: I'm not condemning LDH, I think it's the nuts in most situations. I'm just playing the voice of balance.)
LDH takes more water to fill up. In the previous example, that 450 gpm hydrant is going to spend roughly 2.2 minutes just filling 1000' of 5" hose. The same 450 gpm would fill 1000' of 4" hose in 1.4 minutes or 1000' of 3" in 49 seconds. (1000' of twin-laid 3" in 1.6 minutes.)
Maybe a hydrant isn't the best example, lets look at rural operations:
The engine drops one end of a 5" line and forward lays up a 1200' lane to the burning barn and sets up to start fighting fire. The first 1800 gal tanker/tender that shows up to pump water to the engine spends 2/3 of its water filling the supply line before it's actually contributing anything to the engine's pump. The same scenario with 4" line only uses about 780 gal to fill the 1200' of hose and leaves a little over 1000 gallons for the engine to use.
Like I said, I'm not saying these things outweigh the amount of water 5" hose can move after it's filled up and the water supply is in steady state. It's just something to think about...
Fairland Volunteer Fire Department
[This message has been edited by Todd Trimble (edited October 22, 1999).]
10-22-1999, 04:56 PM #8FyredUpFirehouse.com Guest
While the time thing may be true, what about the time it takes to back a tanker up a 1000 foot driveway? That can't be done in 2.2 minutes. At least not safely. I would still rather lay the 5 inch up the driveway and count on my shuttle to bring me the water I need to fill it. No matter how you slice it the 5 inch wins on efficiency of water flow.
10-22-1999, 11:31 PM #9TRUCK 110Firehouse.com Guest
Fyredup..I concur with you all the way..As far as water filling the line..well it takes 3/4 gal /ft to fill 4"..and 1 gal /ft to fill 5"..
Now I have a scenario for Todd Trumble..you are on a narrow Road, and drop a Single 5" Line, now this line maybe the only Line down for that 1200',but if you have that good Tanker System in place..the 5" at the 150 psi (as the Book says) will flow @ 1400 gpms vs. 830 gpms for 4" from Drop Tank to Attack Pumper..Well that is a substantial gain.. Almost the Entire Flow of a Single Inlet Supply line..as the Manufacturers state for Maximum Water on Single 6" Inlets on Modern day Pumpers (1500 gpm).LDH is LDH..regardless of the Water Flow, and no one as Far as I know says that Supply hose has to be full to work. Also for those not in the know, 5" will flow virtually at 1 psi, and may not collapse like 4" does at this point, due to its Volume size. I'm no Virtuoso on LDH, but I had to take a 3 day course on it For my Degree. The Biggest drawbacks to 5" is that it takes @ 40% more Hosebed space, and weighs about 50% more than 4", but we will overcome that..
Thanks for the Post..Be SAFE
[This message has been edited by TRUCK 110 (edited October 22, 1999).]
10-22-1999, 11:51 PM #10SOMLFirehouse.com Guest
5" with sexless couplings is the best by far!
when you need h2o you need h2o.
storz couplings with a few adapters and you can overcome anthing.
We use the 5" for hydrants and for tanker/pool operations yes, it takes a little more h2o to fill it but it is worth it.
10-29-1999, 11:20 AM #11edfcFirehouse.com Guest
The five inch is the way to go.
11-09-1999, 12:12 PM #12ChapCaptFirehouse.com Guest
We went to 5" about 4 years ago and love it. We have a lot of long lays where it has been great.
One thing noboby mentioned about 5" is placement. If not layed properly you block access for other arriving apparatus, traffic and so forth. Our pre plans take this into consideration, especially when we expect to call in apparatus from neighboring depts. We have specified which way they are to come in. We all know in the heat of the moment it does not always go according to plan, but something to to think about. 3" and possibly 4" you may still drive over if necessary. Hose ramps for 5" in are huge, we don't use them. Hopefully we lay the hose right and close roads if we have to.
11-09-1999, 03:54 PM #13DED1645Firehouse.com Guest
5" is definately the way to go. You don't have the friction loss as running dual 3". And if you run street hydrant w/ your 5" you can boost poor hydrant pressure w/ an extra engine. The only thing I don't like about it is we have 4500' of it. And we have dropped the entire bed of hose.
Presently Lindenwold,NJ(I'm not a member of any of this District's dept's.)
11-11-1999, 08:15 PM #14SBrooksFirehouse.com Guest
I have a few questions for users of 5"
#1 do you drop it for every report of smoke or better call?
#2 when to you charge it?
...as soon as the pump operator is ready?
...as soon as another engine arrives at the hydrant?
...as soon as the ladder truck is in position?
#3 Im not an engine man but a truckie...nine times out of ten I have to drive over and straddle the three inch that has been laid in by the first engine. As often as not, it hasn't been charged yet, no biggie, but if it has, still no biggie. If it was 5"....? What do you do to avoid this problem?
#4 do you also carry 3"? If so when do you use it. In my area a pumper could drop all 1200' of its supply and still flow 250+gpm off of hydrant pressure...more than enough for one companies first line in...We almost never use hydrant pressure, but rather go wagon&pumper, giving us 425 gallons at 1200' or 1200 gpm at 600' through dual lines. In my area I can think of no properties that have fewer than 3 or 4 good hydrants within 600'. Most pumpers have two beds of 600 - 1000' of 3" hose each (I would personally replace one of them with 5" if it were up to me) which brings me back to my question of whether any of you drop 3" for the first arriveing and 5" for others or what.
11-11-1999, 11:22 PM #15FyredUpFirehouse.com Guest
1) Yes, if not by the first in, by the second in engine. Whether to lay or not for smoke showing is up to the first in officer. Report of flames or flames showing gets a straight lay in by the first engine.
2) When the MPO calls for it to be charged.
3) Lay in at 10 or less MPH and try to keep as close to the side of the road as possible. We have no truck so we still need room for other engines and squd companies.
4) We carry 400 feet of 3 inch for standpipes and deluge operations. It is not used for supply. We can flow 1000 Gpm at 1000 feet from a hydrant. With no other pumper boosting the water.
11-12-1999, 10:33 AM #16ChapCaptFirehouse.com Guest
We have 3 engines, 2 with 5". One of those engines is the supply engine. Most of the time the first due goes straight to the scene and does not lay at all, we wait for the supply engine. The supply engine stages at the nearest hydrant until given further orders by the first in officer or chief.
We alternate first due duty between the other 2 engines, so sometimes it is the one with 5" inch sometimes not.
Our main reason for going to 5" was the long lays we have in a few parts of town. Some of those lays exceed 3,000 feet. We need two engines to make the lay and one to pump from the hydrant so we have preplanned where each one has to start dropping hose. The first due stages at the closest point to the alarm as possible, hoping the chief gets there first and determines if a lay is needed or not. If the engine gets there first, they must lay, its not worth going to the scene and finding you have to go back and lay in.
The supply engine lays from the hydrant to where the first engine started. The third engine stops at the hydrant, creates the loop into the Blakes valve and starts pumping.
[This message has been edited by ChapCapt (edited November 12, 1999).]
11-12-1999, 11:03 AM #17LT 1E4Firehouse.com Guest
We went to five inch hose about six years ago and I find no problem with it as far as supplying a lot of water. As mentioned in a previous post, the placement of the five inch in the street is important. Once it's charged, there is no driving over it and it's nearly impossible to move because of the weight of the water. We also use it to pump to an arial ladder. It helped save a lot of time by eliminating the "lay two in and one back" to an arial when we only had
2 1/2 and supplies much more water to the arial than the three 21/2's. Go with the five, you won't be sorry.
11-12-1999, 03:42 PM #18INDY FIREFirehouse.com Guest
In most cases in the city with hydrants,BIGGER is BETTER...
[This message has been edited by INDY FIRE (edited November 12, 1999).]
11-16-1999, 09:14 AM #19WaynoFirehouse.com Guest
This was a good Post. Thanks to the orriginator. We run dula 3" and have been for many years (Longer than I am old). 2 monthas ago we purchased 1500 feet of 5" along with all the appliances. We still plan on carring 500 of 3" for those instances where we may use it for stand pipes etc. Thanks again a for a ton of use full information.
No Dragon To Big To Tame!!
12-06-1999, 12:09 AM #20shoopyFirehouse.com Guest
As a user of 5" hose we love it and unless you haven't used it then don't knock it.
You can look at all the spec information you want but the reality is when you need water why would you want to risk your interior crews by have such a small line like a 3 or 4 inch supply line and a 2 1/2 that to me is a kick *** hand line not a supply line. What you should do is get a nearby dept. that has 5" and hook up equal lengths with your dept. using 3" and record the pressure and gpm's. When you look at it that way then the reality sets in that you have major water flow. Yes, it is a pain to pick up but it would be worse picking up all the 3" laid that one 5" can do.
I won't knock those who use 3" cause sometimes it can be useful but we primarily use it for a nurse line.
12-16-1999, 11:54 PM #21Tom65Firehouse.com Guest
I work in a small Federal Government departmant in Eastern Oregon.
I was talking to one of our new Capt.about changing from 3inch to 5 inch hose. He told me that the chief would not change to 5 inch because it is to heavy and our hydrents have to low pressure.
what can I do to change there minds?
12-17-1999, 12:53 PM #22SBrooksFirehouse.com Guest
Around here, wagons that don't lay in aren't likely to get water...a line is dropped for every report of fire or smoke in a building, even if it is only a 3" line. The only exceptions are when: A) there's a hydrant for the pumper to hit right in front of the fire building (usually where the truck needs to be!) B) When a truck, squad, or a chief arrives first and reports for units to stand by. Typically when we go for auto alarm, etc. One engine will standby for the reverse lay while we investigate. I've never seen a buiding burn down for lack of water (in a hydranted area), and all we have for the most part is 3".
12-17-1999, 11:26 PM #23LynFD49Firehouse.com Guest
5 Inch, 5 Inch, 5 Inch, 5 Inch, 5 Inch!!!!
Can I be any more forceful?!
1200' in 100' sections should suffice in most situations. If you have the ability, cary more on the 2nd due piece.
Dont forget to make 1 25' and 1 50' "curb jumpers" for when the hydrant is located infront of the structure, or if an engine is needed to fill tankers from a distant hydrant.
Stay Safe and Stay Low
05-04-2007, 04:07 PM #24
- Join Date
- Apr 2007
Five Inch LDH / 3 Inch Intake
Just would like to get some input on the following.
When using 5 Inch LDH, do you connect to your pumper's steamer or do you reduce it and go into a smaller intake. If you have operated both ways in the past, what were your results? what kind of flow rates did you oberserve?
05-07-2007, 02:01 PM #25
- Join Date
- Jun 2003
- Irwin, PA
Back from the dead after almost 8 years
Nice to see someone who can use the search function!
We use piston valves on our steamer connections with a pressure relief valve. The relief valve is important to get the air out of the line when you charge it, you would be surprised how much air it holds. Not something you want going through your pump. The relief valve also is a good indication when you have some lever puller on the pumper sitting on the plug that is being over zealous with the throttle on your supply line. I believe most LDH is rated at 200 psi so you don't want to go crazy with the pressure on them.
The piston valves are a bit of a hassle to take off when you draft, however. There may be valves available that do both, allow hook up to a supply line or to hard suction for drafting.Thomas Anthony, PE
Structures Specialist PA-TF1 & PA-ST1
Paramedic / Rescue Tech North Huntington Twp EMS
The artist formerly known as Captain 10-2
No, I am not a water rescue technician, but I stayed in a Holiday Inn Express last night.
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