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Post by 2Truck on Oct 8, 2003 22:00:40 GMT -5
What type of nozzles does each company use? Smooth bore? Automatic? Selectable gallonage? Automatics are great fireman proof nozzles since they are relativley easy to use (open the bail and adjust the stream). While the selectable nozzles require a little bit of thought by the nozzleman as to how much flow is going to be needed. As for smooth bores, they provide a LOT of water with a lot less reaction force. Another advantage of smooth bores is that they operate at any pressure, unlike the fog tips, which makes them good for high rise packs and long line streches.
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Post by 911wacker on Oct 10, 2003 7:47:02 GMT -5
Automatics are great IF they are pumped to the proper pressure to achieve the flow rate that is required. I think that this is tough for some departments given the fact to be affective on most any 1 3/4" handline to achieve 125 gpm you need to be pumping at or above 150 psi. I am willing to bet that some of the departments are only pumping these lines at around 100 psi, which would produce a nice stream with an automatic but lack the gpm's to do an effective job giving you a false sense of security.
My own personal opinion is that fixed gallon simplest form and probobly the best form of nozzle for the Volunteer Fire Service, you know that you are flowing x gpm and if the stream is poor - boost the psi.
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Flynn
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Often imitated; Never Duplicated
Posts: 45
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Post by Flynn on Oct 10, 2003 11:05:19 GMT -5
Good call there Wacker! The Automatic nozzle is only as good as the MPO (motor pump operator for your FDNY fans) and the size attack line it is attached to. This type of nozzle requires the MPO to truly figure out all the hydraulics of pump operations. It is much more than the standard "give it a little more throttle". Does coupling an Automatic nozzle to 1-1/2" hose make sense? As previously stated by Wacker, depending on circumstances, 150 psi on an 1-3/4 " hose may produce flows of 125 gpm. Unless you are using a low pressure automatic, you need 100 psi just to open them up (function). This is 100 psi nozzle pressure, what do you think your GPM is? The stream will appear effective, but do you have the desired or required flow?
Conversely, adjustable gallonage, requires a knowledge of the attack team to set the nozzle to the appropriate setting during use. This basically turfs the requirements back tothe attack team instead of the MPO. These nozzles work great, again, communications between the MPO and the Attack team are vital.
Monroeton runs all single gallonage nozzles. I would like to say its for the reasons that Wacker has stated, however and truthfully, it has been cost related. We have talked about changing to automatics, however we would then have to change all our attack lines to match the capabilities, train quite regularly on there use and work with the MPO's more often. I would venture to say that the single gallonage is the most cost effective, user friendly nozzle still available.
Smooth bore nozzles are where its at. Penetration to the seat is the key! Do they offer protection, NO! Do they cool the ceiling in a quick sweep, NO. Will they deliver a hard-hitting, full applicable gallonage to the beast, YES. Should they be on every attack line, NO. Should they be attached to one preconnect on every engine, YES, along with a preconnect large caliber line such as a duece & 1/2 or 3".
Now you all know why I specialize in Truck Op's and being a Truckie. You Hoseheads have way to much stuff to think about.
See ya vertical!
Tim
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Post by 911wacker on Oct 10, 2003 11:56:47 GMT -5
Just to give some of you a idea of friction loss- 200' 1 3/4" line flowing 125 gpm will lose about 48 psi - that means only 102 psi at the nozzle if your pump pressure is 150 psi. Those of you who use auto's can see that it becomes tuff to achieve desired flows at low pressures as you can see further below. 150 gpm will require 170 psi at pump 175 gpm will require 195 psi at the pump Thats alot of pressure!!! ;D 2" 200' line flowing 175 gpm with same nozzle only needs 150 psi at the pump!! Something to think about?!?!? "ENGINE 2 TO COMMAND - CANCEL THE TRUCK - FIRE OUT"
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Flynn
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Often imitated; Never Duplicated
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Post by Flynn on Oct 10, 2003 12:56:16 GMT -5
Wacker, you Mathematician you! Just to add an additional to Wackers theory on pump evolution...... Pull past the bldg. and do your calculations. Give the TRUCK side one and at least a corner! You can pull more hose , but you can't pull more ladder! ;D ;D ;D Damned Hoseheads! "Headquarters, Tower knocked it with the cans, place Engine 2 available, Kaye," ;D ;D ;D ;D Tim
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Post by Matt Russell on Oct 10, 2003 20:48:12 GMT -5
So that's what dispatchers do at work..........sit there and read books about friction loss and play with the calculator on the 'puter to get the right answer.
I would agree automatic is the way to go where we are. Not sure what the rest of you do but, we sat down and did the friction loss thingy 1 time and then labeled the guages as to the psi needed at the pump to get 110lbs at the tip. Is this necesarrily the proper way to do it NO! but then agin for the most part our highest structure is 2 story hence not gonna loose too much from the gound to the second floor AND it prevents the stand in pump operator from racking his brain as to the correct pressure and it prevents the wasted airtime getting the proper set everytime.
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Post by 2Truck on Oct 10, 2003 21:56:00 GMT -5
Hey Tim just think we don't have to do any nozzle calculations with a can! ;D Just have to know how to use it. Besides you engine boys don't need a lot of pressure to do overhaul after the trucks done. ;D ;D Command from the Truck, mark control go ahead and let the engine mop it up.
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Flynn
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Often imitated; Never Duplicated
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Post by Flynn on Oct 11, 2003 7:30:29 GMT -5
Matt;
How you'all test and layout your pump panel for the use of automatic nozzles is exactly how it should be done. Consistant training and evaluation of these type nozzles will make for a better use of the product. To simply go out and buy these, without a thought process as to need/worth is ridiculous. Hell, I have guys in my own company who want to purchase automatics and when I ask why, I get the "deer in the headlights" look.
Please don't get me wrong, the use of the automatic nozzle, when coupled to the proper dia. hose is the way to go. However, as with all appliances, training and adaptability to your operations is the key to there success.
On a side note, and off-topic - If I had your tanker with a prepiped deck gun coming first in, I wouldn't hesitate doing a true blitz attack. This has nothing to do with water conservation, but with the gallonage available, you could do one monster of a job!
Also, to set the record straight, Kim asked for a tanker from my company. I heard no request for water to be included. I think we provided what was asked for! ;D ;D
Tim
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Post by Robert Repasky on Oct 14, 2003 17:11:35 GMT -5
Finally, someone made sense and suggested a 2" attack line with an automatic nozzle. More GPM, easier to handle than a standard knob on an inch and a half..... One question to Tim: If you're such a "Truckie" what the hell are you doing in Monroeton, PA?
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Flynn
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Often imitated; Never Duplicated
Posts: 45
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Post by Flynn on Oct 14, 2003 18:37:09 GMT -5
Robbie; Ya' got me there brother! My chances of doing truck work in Monreoton are Nil & Void ;D Now when I am in Towanda, I am Bill Sheets's biggest pain in the butt! You know "Can I go in coach, please!" Heck look at you, I am one of your Chauffeurs, and even then I can't catch a JOB, wasssup with that? I used to think it was becasue the Sayre FD had an excellent Fire Prevention Program, now I am beginning to think its PERSONAL! Anytime, Anywhere baby! Give me a can, a hook and a saw! See ya vertical! Tim
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