Thread: pumper plumbing
04-11-2001, 11:26 AM #1ONTFFFirehouse.com Guest
was just wondering if anybody is trying to eliminate behind the panel valves and controls and using more valves and thieves etc at the discharges themselves to eliminate costly repairs, does this actually save anything? does it improve ops
04-11-2001, 11:32 AM #2LHS*Firehouse.com Guest
04-12-2001, 11:58 AM #3CAPTAIN WHOFirehouse.com Guest
You can always reduce the number of Discharges and use external gates, wyes etc.
However in Canada a ULC rated pumper (in Canada NFPA is a guidline only) you must have a 2.5"/65mm discharge for every 1000 lpm of flow.
Now a LDH discharge 4" with 3" pipe will count as 2 2.5" discharges. So a 6000 lpm /1250 Igpm / 1500 USgpm pump will require the equivilant of 6 2.5" discharges. Crosslays and Monitors/Deck guns are in addition to this and can not be counted.
Each unit must also have 2 steamer port suctions and 2 pony suctions. (more valves).
The internal controls are for warmth. Most Units in Canada have fully enclosed pump houses with any where from 24,000 to 48,000 btu's worth of heaters to pervent freeze ups. Anything mounted out side the "panel area" is subject to freezing.
Of course in Canada we don't have ISO but we do have IAO, Insurance Advisory Organization, Who will not recognize a Non ULC rated Pumper for water flow capacity.
NFPA also states the same that there must be a min of 2 2.5" discharges on any pump over 750 US gpm. But sufficent Discharges to meet flow capacity of the pump. Eg 750 pump would need 3 2.5" disharges. a 1000 gpm pump would need 4 2.5" or 2 2.5" and 1 3.5".
With the units above the Attached aerial water ways are usable and credited with 1000 gpm flow. So you can get by with the min 2 discharges off the pump.
All discharge valves must be controled at the operators position. Secondary valves are allowed if requied for special applications. But you must still have the primary operator control for the min discharge requirement.
I hope this sheds a little light on why all that stuff is behind the panel.
Unless it has an aerial with permanent water way. Your going to have a lot of valves.
04-12-2001, 01:51 PM #4ONTFFFirehouse.com Guest
thanks for the info, here we have open and enclosed pump panels and as long as we're flowing water and keep the heater on have never had a problem, as for the discharges i agree we should all follow the rules (ie control at operators station) but lets use that two and a half inch discharge and make it do more, things like this is what i'm gettin at, keeping hose where you can reach it, so to close this is it ok as long as you are flowing the required amount or do you require the proper # of discharges, we both know its the gallons of waater properly applied that puts it out, is there a reason why they require two and a halfs?
04-12-2001, 03:48 PM #5LHS*Firehouse.com Guest
Would your fires still go out if you didn't have a pump panel? Let's pretend just for a second that the makeup of most NFPA committees have a lot of folks selling stuff.
How many things on the minimum standard are actually safety??? How does a flow meter and a pressure gauge required on an LDH discharge protect the hose from bursting? It doesn't! A dump valve set at 185 psi is the only thing that would keep the line from bursting. Plus it costsless.
How often do yo pump four lines at four pressures? Most firefighters cannot even expalin how to do it at a fire. Anyone want to give it a try. Step by step how to get four pressures to four lines at a fire?
If you didn't have 14 pressure gauges on the pump panel would your fires still go out? Could you get along just fine with just one for incoming and one for out going pressure?
Is there any reason having four water thiefs without linkages, gauges and drains wouldn't work as well as the conventional panel with 98 things on the side?
If you could push just one button and the pump pressure was autuomatically set and the vehicle maintained that pressure and then you simply pulled your hose and opened the spigot for the hose. What else is there?
Could you prefigure what you needed to pump like a HVAC system? Say your preconnects consist of the following:
a 400 foot 2" line with a fog tip flowing 185 gpm needs 210 psi ep,
a 50 foot 1 1/2" fog line flowing 95 gpm at 100 psi needs 111 psi ep,
a 150 foot 3" line with a portable monitor attached with a smooth bore tip flowing
1000 gpm needs 175 psi ep.
a pair of 150 foot 1 3/4" fog lines flowing 150 gpm at 75 psi needs 127 psi ep.,
a 750 gpm fog deck gun needs 110 psi ep,
a 1250 gpm fog ladder pipe on your squirt 180 psi,
a 150 foot 2 1/2" line with a 1" tip needs 63 psi ep.
Is there any reason one pump pressure can't work for all of them? I can't see any reason.
If we use restricting plates HVAC style one pump pressure does all. Simply pump the highest needed pump pressure 210 psi.
So how does one number work for 7 different hose lines with varing lengths, diameters, flows and tips? On the line requiring 63 psi pull out the gasket and place a thin piece of aluminum plate with a hole in it, then place the gasket over it. The hole is sized to flow 210 gpm at 210 psi, Next the 965 gpm line gets a hole that needs 210 psi to flow 95 gpm, the 150 gpm lines get a hole sized to flow 150 at 210 psi, and so on.
Each line would get the ideal flow and NP.
What is nice on a quint with a deck gun, it is pretty hard to create two equal master streams when the ladder pipe needs 180 and the deck gun needs 110. The restriction plate behind the nozzle allows two perfectly ballanced streams.
There is less than 250 rpm difference at draft pumping 250 versus 150 psi according to the UL pump plate.
What if you add another length of hose? you'd lose 6% of the flow from the first line or 9 gpm. Would anyone know??? Would anyone care? The second line the trash line would lose 29% or 27 gpm. A kink could do that. The bomb line would drop 17% or 162 gpm. I doubt many can tell the difference between a 1000 gpm stream and a 830 gpm stream. The cross lays would drop 20 gpm or 14%. The sb 2 1/2" would see a drop in flow of 18% or 37 gpm.
An increase of an increase in EP of 13 psi per length of added hose matches all the flows up again. Ifabsolute perfection was essential.
Would it be easier to teach everyone to push one pre-set button that makes the pump, discharge one pressure and in the rare event hose was added to a line add 13 psi or teach all the hydraulics needed to do anything?
Why have a control panel? When you built your house did you ask your builder to put al the light switches and faucet handles at the front door? I guess it would make things pretty tough running to the front door to turn the bathroom light on then run back to flush and run back again to wash.
I guess that is why so many lines get charged in the bed. Pretty hard to screw up when you see the hose is connected to the faucet you are about to open. I guess that is why there are so many controls, so many things to break because we want to own all this stuff.
For 50 years pumpers had an intake and a discharge gauge. Most had exposed valves. Have we out smarted ourselves with unneeded complexity??
These guys don't have a control panel, linkages, and operator panel. Their rigs are fully automated. Their fires go out just fine.
Out here we've done one pressure for five lengths of hose and four hose sizes for every fire for 6 years.
What are your thoughts???
04-12-2001, 04:37 PM #6ONTFFFirehouse.com Guest
LHS, we're definitely thinkin the same way, you have different requirements in your area and vice versa but we are after the same goal, puttin out fire! I agree, the simpler the operation of the equipment, the easier it is on everybody, in my department we use automatics (TFT handlines)on all our lines, our rig is set up with 2 250' 1 3/4's in the crosslay and 2 off the back, a 400' deadlay of 2 1/2 is in one bed with 800' in the other for supply issues, the deadlay has an automatic available nearby, the pumper itself is a Volvo FE42 with a Superior body and Hale 1050 pump carrying 900 gallons and A&B foam, yes we rely on our relief valves and nozzles when at a fire to make up for variations in pressure, we also carry all the standard pumper accesories, the only problem is there are discharges all over and things are sorta hard to reach, hence my topic of trying to better set up the pumper, apparently someone else has determined that we should have so many 2 1/2 dis. for so much capacity, but, why have central control of valves etc if (from my experience)most times you have to be at that discharge or suction to see if its operating properly anyway, better make damn sure you throw the right lever, by the way I got started on this area of discussion after reading an article of yours, the rest of my department consists of another 840 gpm /1200g pump/tanker and two 2400g tankers
04-12-2001, 11:52 PM #7dfwscottyFirehouse.com Guest
You want the shortest distance between your handles and the actual valves. Less to go wrong over time. When we went to look at the progress in the construction of our quints, the discharge handles weren't lined up with each other. We asked if they could be lined up with each other and they said it could be done but it would add more turns. Their reasoning was that the less connections between the dishcarge handle and the valve means less trouble in maintenance down the road.
04-13-2001, 01:29 PM #8Engine 224Firehouse.com Guest
Question for LHS. How do you figure the size of the holes in the restrictor plates?
Did you use trial and error or do you have a hydraulic engineer in your department whose day job is to figure out how high those irrigation gates have to be raised to fill the ditches surrounding downtown Fallon?
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