Thread: Pressure?

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    Default Pressure?

    hey all, i am currently taking hydraulics class, and am curious to how much gpm/psi is coming through the nozzle when it is set to flush?
    thanks

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    Quote Originally Posted by alpha4 View Post
    hey all, i am currently taking hydraulics class, and am curious to how much gpm/psi is coming through the nozzle when it is set to flush?
    thanks
    there are 3 gpm at 10 psi

    Seriously, you need to give a little more info. Hose size, length of hose, pressure at the pump would be pretty helpful

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    What size hose, what brand of nozzle?
    IAFF

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    Sorry about that,
    Let's say a 1 3/4 inch hose, 150 feet,
    With a manual adjust fog nozzle,
    Not sure of

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    I've got a better idea. Why don't you take the class first.

    The GPM and PSI will be highly dependent on the GPM and PSI at the pump.

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    Default Mid Range Akron Turbojet

    Making the following assumptions: (I know - makes an *** out of you and me)
    150' of 1 3/4" with original nozzle setting at 200 gpm needs 166 psi of engine pressure. Then holding the EP at that value and allowing for the opening of the nozzle baffle to approximate 1 1/2" opening. The nozzle pressure of 20 psi equates to 300 (301) gpm, and 300 gpm through 150' of 1 3/4" hose has an Fl of 148 psi or still holding 166 psi of EP. So my guess is about 300 gpm on flush with a reach of about 35 feet. Run your problem on an engine with a flow meter and tell me how close I am to the actual.
    Kuh Shise

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    Quote Originally Posted by ScareCrow57 View Post
    I've got a better idea. Why don't you take the class first.

    The GPM and PSI will be highly dependent on the GPM and PSI at the pump.
    did you learn that from the Sears & Roebuck self study guide there Wizard?

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    Quote Originally Posted by LT2387 View Post
    did you learn that from the Sears & Roebuck self study guide there Wizard?
    Don't be silly - Its covered in Thermodynamics

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    Another example of a topic where ScareCrow had absolutely nothing of value to add but he still couldn't help himself and he had to post anywys.

    When you have nothing to add WHY do you feel the need to post?
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    Quote Originally Posted by alpha4 View Post
    Sorry about that,
    Let's say a 1 3/4 inch hose, 150 feet,
    With a manual adjust fog nozzle,
    Not sure of
    Is the nozzle an adjustable nozzle? What brand?

    To answer your question, we need to know what kind of nozzle and if it is an adjustable gallonage nozzle. This will make all the difference.
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    Who really cares how much water comes out of the nozzle when you have it on FLUSH!

    I hope enough to clean out the nozzle if you need to flush it.
    Stay Safe and Well Out There....

    Always remembering 9-11-2001 and 343+ Brothers

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    Quote Originally Posted by ScareCrow57 View Post
    I've got a better idea. Why don't you take the class first.

    The GPM and PSI will be highly dependent on the GPM and PSI at the pump.
    Epic fail.
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    Quote Originally Posted by CaptOldTimer View Post
    Who really cares how much water comes out of the nozzle when you have it on FLUSH!

    I hope enough to clean out the nozzle if you need to flush it.
    Because if you maintain the correct nozzle pressure it can actually give you MORE WATER than the normal gpm flow of that nozzle. The pattern is more broken, but is more than adequate for interior room fire scenarios. I always looked at it as extra emergency water if needed. Kind of like that twisty thing on the end of the TFT Dual Farce nozzle.
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    Quote Originally Posted by ScareCrow57 View Post
    I've got a better idea. Why don't you take the class first.

    The GPM and PSI will be highly dependent on the GPM and PSI at the pump.
    "Just when I think you have said the stupidest thing ever you just keep posting."

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    Quote Originally Posted by FyredUp View Post
    Another example of a topic where ScareCrow had absolutely nothing of value to add but he still couldn't help himself and he had to post anywys.

    When you have nothing to add WHY do you feel the need to post?
    There is nothing of value to add becuase the question is poorly worded and doesn't even come close to giving enough information. However Mr. know-it-all makes 100 assumptions then gives a meaningless answer.

    But hey, here is another one for you. How fast is a fire truck????

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    Quote Originally Posted by ScareCrow57 View Post
    I've got a better idea. Why don't you take the class first.

    The GPM and PSI will be highly dependent on the GPM and PSI at the pump.
    "Highly dependent," you say? Holy crap, you're smart!

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    Stupid is as stupid does. T,C,

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    Quote Originally Posted by FyredUp View Post
    Because if you maintain the correct nozzle pressure it can actually give you MORE WATER than the normal gpm flow of that nozzle. The pattern is more broken, but is more than adequate for interior room fire scenarios. I always looked at it as extra emergency water if needed. Kind of like that twisty thing on the end of the TFT Dual Farce nozzle.
    The Elkharts that my department uses, has a flush on the nob, but it isn't going to give you an adquate flow to do much. As the lady said anything is better than nothing!

    BTW we tried TFT's and got rid of them as no one liked them and stayed with Elkhart.
    Stay Safe and Well Out There....

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    Quote Originally Posted by CaptOldTimer View Post
    The Elkharts that my department uses, has a flush on the nob, but it isn't going to give you an adquate flow to do much. As the lady said anything is better than nothing!

    BTW we tried TFT's and got rid of them as no one liked them and stayed with Elkhart.
    By the very nature of the flush setting at equal nozzle pressures it HAS to give you more water. All the flush does is move the baffle out farther.

    Of course, since you are enlarging the opening on the nozzle you have to increase the engine pressure to maintain 100 psi at the tip.
    Last edited by FyredUp; 11-27-2009 at 03:17 PM.
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    Quote Originally Posted by ScareCrow57 View Post
    There is nothing of value to add becuase the question is poorly worded and doesn't even come close to giving enough information. However Mr. know-it-all makes 100 assumptions then gives a meaningless answer.

    But hey, here is another one for you. How fast is a fire truck????
    Look Super Genius, I have run tests doing this exact thing, and with the nozzle I listed in the other similar topic I got the results listed. n Have you run these tests? have you ever even thought of it? Maybe wikipedia can be your friend again.

    See realworld experience can be your reference. The only stickler is you have to have some real world experience to draw from. That surely is your biggest downfall.

    It should be as fast as the speed limit and driving conditions allow. Have you ever been in a REAL firetruck?
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    Quote Originally Posted by FyredUp View Post
    Look Super Genius, I have run tests doing this exact thing, and with the nozzle I listed in the other similar topic I got the results listed. n Have you run these tests? have you ever even thought of it? Maybe wikipedia can be your friend again.

    See realworld experience can be your reference. The only stickler is you have to have some real world experience to draw from. That surely is your biggest downfall.

    It should be as fast as the speed limit and driving conditions allow. Have you ever been in a REAL firetruck?

    That is great. I am glad you have. However, your test are only meaningful if they operate within the constraints of your experiment. Since the original poster did not give the constraints your answer is only some what meaningful. Basically, it is impossible to answer his question with the information given. You did however, provide the answer in terms of your question. Which BTW, could be two different questions but similar.

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    Damn! I thought all this time that real nozzles only had two positions - OPEN and CLOSED! What's all this straight, fog, and flush nonsense about anyway? Are you talking about one of those nozzles with more o-rings, springs, gaskets, and pistons than the spaceshuttle?
    "If everyone is thinking alike, then somebody isn't thinking."

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    Quote Originally Posted by ScareCrow57 View Post
    That is great. I am glad you have. However, your test are only meaningful if they operate within the constraints of your experiment. Since the original poster did not give the constraints your answer is only some what meaningful. Basically, it is impossible to answer his question with the information given. You did however, provide the answer in terms of your question. Which BTW, could be two different questions but similar.
    Look you pompous, arrogant ***, I offered data based on experiments using flow meters and inline pressure gauges to the original poster.

    What did you offer? This totally worthless piece of crap: "The GPM and PSI will be highly dependent on the GPM and PSI at the pump." This says absolutely nothing to the original poster's question.

    The simple facts of the flush feature are these:

    1) When you set a nozzle to flsh it opens the space between the baffle and the nozzle increases. The idea being so debris can more easily flow through.

    2) At the rated pressure of the nozzle, whether 100, 75, or 50 psi, opening the flush feature will flow more water because the opening is larger.

    3) If the pressure is not increased the flow may increase slightly, but the stream will be more broken and reach will be affected.

    Maybe it's time for you to do another wikipedia search you diddling half wit.
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    Quote Originally Posted by FyredUp View Post
    Look you pompous, arrogant ***, I offered data based on experiments using flow meters and inline pressure gauges to the original poster.

    What did you offer? This totally worthless piece of crap: "The GPM and PSI will be highly dependent on the GPM and PSI at the pump." This says absolutely nothing to the original poster's question.

    The simple facts of the flush feature are these:

    1) When you set a nozzle to flsh it opens the space between the baffle and the nozzle increases. The idea being so debris can more easily flow through.

    2) At the rated pressure of the nozzle, whether 100, 75, or 50 psi, opening the flush feature will flow more water because the opening is larger.

    3) If the pressure is not increased the flow may increase slightly, but the stream will be more broken and reach will be affected.

    Maybe it's time for you to do another wikipedia search you diddling half wit.
    Don...that wasn't nice... we all know that Scarecrow uses his full wit when he diddles...
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    Half wit? That's giving that asylum escapee 50% more credit than he deserves.If brains were powder there wouldn't be enough to blow his nose. T.C.

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