Trash pump, vs High pressure fire pump?

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Your questions could be clearer IMO. Maybe I didn't read it right?

By changing the resistance of the system you move back on the curve. With centrifugal pumps you can reach shutoff (dead head) from adding more hose or adding elevation at the discharge. The higher you go up with the discharge the less flow and pressure you will get.

Clearer? Nope intentionally vague. Pumps...elevation...you work it out. The prize makes it all worthwhile.
 
I've never run over an active hose lay. Sometimes though, if things get a little confused and a crew moves on and somebody else is supposed to come along and roll hoses and they don't show up and it's night time and we're just plain damn tired of building speed bumps over the hoses and we remember the last time we had to listen to somebody snivel because the speed bumps were too high and it took them too long to dig their hoses out 0r it's several days past cutting line and we're into remediation and the damned hoses are still out there and everybody you've mentioned it to has ignored the information...well, you know. Things happen. ;)
You neglected to mention how you enjoyed every minute of driving over the hose.
 
Are you referring to the loss of vacuum level before cavitation at higher elevations reducing capacity on the suction side of the pump?



Mr. HE:cool:
 
As you go up in elevation you loose atmospheric pressure. So at sea level you have 14.7 psi pushing water into your pump once it grabs it. At 10000 feet you have 10 psi of air pressure pushing the water into your pump. This becomes a problem when pump testing fire trucks. Also you loose some performance as water temps increase.
 
As you go up in elevation you loose atmospheric pressure. So at sea level you have 14.7 psi pushing water into your pump once it grabs it. At 10000 feet you have 10 psi of air pressure pushing the water into your pump. This becomes a problem when pump testing fire trucks. Also you loose some performance as water temps increase.
Cfaller takes the gold! Yep it is the weight of the air column that pushes water up the suction hose. Less weight means less ability to draft.

Cfaller pm me your address and I will ship your prize out as soon as possible.
 
Alright, I'll give you this one. ;) I will say that although I did mention NPSH I did not mention how changing elevation impacts it. However, if you were designing a pump system to be built you would take that into consideration and design it for the environmental conditions. However, if you bought an existing pump/system and wanted to use it at higher elevations you definitely should consider the impact. Most of my pump experience is with stationary systems and not ones that change elevation. Here is a good graph and article explaining suction head loss vs elevation. You can see that you lose 9 ft of suction head loss by going from sea level to 8000 ft.

image.jpg

http://www.grpumps.com/educationsafety/article/1447
 
Well, I wandered over here again by mistake, but I might have a suggestion for a fire fighting pump. I used to do hydroseeding, so I have sprayed a little water a time or two. Now most of your hydroseeing companies use a souped up trash pump for spraying out the slurry. Unlike a regular trash pump the intake which will have the same size entrance and exit ports, the hydroseeding pumps will use a larger suction port. My old finn had a 3x2 centrifical pump. The suction port was 3in dia and the discharge was 2 inch. Now I know every body is concerned about running long hose, well my Finn with a 25hp kholer engine would pump a thick hydroseeding slurry thru 400ft of 1 1/2 inch hose on level ground and still spray a stream out the nozzle of around 100ft, giving me about a 500ft reach from tank. Going up hill on steep slopes, 30*-40* I could reach as far with the spray pattern with 100 ft of hose as I could if I used 200ft of hose. Going uphill sucks dragging a 1 1/2in hose full of hydroseeding slurry. Pumping vertical I could get close to 200ft which suggest a pressure close to 100psi and I would guess that to be pretty close, altho I never checked to see what the actual pressure was. So I guess my suggestion for someone wanting a fire rig, look at a used hydroseeder, I would stay away from the cheap plastic kind simply because, even tho you are just spraying water, the pumps arent really up to pumping uphill. The Finn's with the centrifical pumps will probably pump as far as you would need to, and if you really want someting that will build a ton of pressure, look for a machine with a bowie gear pump. Bowie, Turfmaker, Kincaid are just a few manufacturers that use the bowie gear pumps. Turboturf also makes a plastic tanked machine that uses a bowie gear pump and because of weight might be the best rig to look for in this situation. Used hydroseeders are fairly reasonable and easy to find. They already have a engine, pump, tank and are often already trailer mounted. Any of the machines I listed would empty a 500gal tank in about 5 or 6 minutes if unchecked, so flow shouldnt be a problem. And added advantage would be that when it came time to reseed your skid roads, you could throw some seed in the tank and spray it on the areas to steep to put your other equipment on.

Alright, going back to cutting firewood and being a old fart now.
 
A pump with a 25hp motor on it is a powerful pump. The only way to really know the pressure is with a pitot gauge and a smooth bore nozzle. The Scout camp I volunteer at needs a water buffalo or a fire trailer but a hydroseeding trailer sounds interesting. Where are those things advertised for sale?
 
I just did a google search for used hydroseeders and hundreds showed up. I would try Craigslist and even Ebay. From what I saw in the machinery trader type listings, most where for mostly large, expensive machines. Hydroseeders come in all sizes from 100gal up to 4000gal maybe even larger. Lots of folks get into the hydroseeing business thinking they will make it rich. They find out it isnt as easy as spraying some seed and water on the ground and soon go bust, and that equipment can usually be bought pretty cheap. On the hydroseeding.org forum, they usually have lots of used hydroseeders for sale and I know Ray Badger of Turboturf, takes in lots of tradein's and usually sales those pretty reasonable. He's located in Penn, so shipping to Ca. might be prohibitive. He also builds specialty spray rigs, but I dont know if fire fighting rigs are part of what he sales. I see all kinds of hydroseeders setting out in the weed patches not being used. Heck, I have a old 500gal, skid mount, machine setting out back, no engine, but the tank and pump should still be good. If someone wanted to build a fire tanker, it would make a good candidate, just mount a engine. Probably not worth the price of shipping. I have already robbed the engine for my wood splitter and have plans for the rest of the hydraulics as well.
 
I just did a google search for used hydroseeders and hundreds showed up. I would try Craigslist and even Ebay. From what I saw in the machinery trader type listings, most where for mostly large, expensive machines. Hydroseeders come in all sizes from 100gal up to 4000gal maybe even larger. Lots of folks get into the hydroseeing business thinking they will make it rich. They find out it isnt as easy as spraying some seed and water on the ground and soon go bust, and that equipment can usually be bought pretty cheap. On the hydroseeding.org forum, they usually have lots of used hydroseeders for sale and I know Ray Badger of Turboturf, takes in lots of tradein's and usually sales those pretty reasonable. He's located in Penn, so shipping to Ca. might be prohibitive. He also builds specialty spray rigs, but I dont know if fire fighting rigs are part of what he sales. I see all kinds of hydroseeders setting out in the weed patches not being used. Heck, I have a old 500gal, skid mount, machine setting out back, no engine, but the tank and pump should still be good. If someone wanted to build a fire tanker, it would make a good candidate, just mount a engine. Probably not worth the price of shipping. I have already robbed the engine for my wood splitter and have plans for the rest of the hydraulics as well.

Engines are easy... what you want for the rest of it. Or at least the pump... Tanks are easy too.
 
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