Steel Pan Posted April 24, 2014 Share Posted April 24, 2014 I heard that the jet should be abouit 2 ft. from the crash box.That doesn't work, need more distance in order to form a water columnthat creates the suction.So, how far from the crashbox does the jet need to be in order forthe jet to work properly? Quote Link to comment Share on other sites More sharing options...
AzNuggetBob Posted April 24, 2014 Share Posted April 24, 2014 (edited) Steel Pan Every jet tube or nozzle Ive ever seen, the venturi jet has always been about 20-25 % down from the entrance of the jet tube/nozzle regardless of tube or hose length. AzNuggetBob Edited April 24, 2014 by AzNuggetBob Quote Link to comment Share on other sites More sharing options...
Steel Pan Posted April 24, 2014 Author Share Posted April 24, 2014 (edited) Say you have a hose 20 ft long.You would place the power jet at aprox5 ft. from the the buisness end?Or, from the crash box? I cut the end off a suction nozzle and put that at the end of a 3ftlength of hose. Installed the suction nozzle at the other end andran a 16ft length to the crash box. (see pic of "assistant" below)Originally I had the two hoses switched, the 3 ft went to the crashbox. That's what I was told to do but it didn't work. Now, I can stand and hold the nozzle with the 3ft hose reaching thematerial for me, no bending over. ( again, see pic of "assistant")I see that as an unexpected bonus. Don't like bendin' over. What I'm goin' for, is to hold nothing but hose and have the suctionnozzle further up line and closer to the crash box.Just like the big boys. Power Jet, Suction Nozzle, and "assistant" are below. Edited April 24, 2014 by Steel Pan Quote Link to comment Share on other sites More sharing options...
AzNuggetBob Posted April 24, 2014 Share Posted April 24, 2014 Steel Pan I see what your trying to do but its a matter of psychics. the higher you hold the jet nozzle out of the water the less suction you'll have. Its like putting a high banker up on a bank rather than lower down in the creek. the raise is going to kill suction..AzNuggetBob Quote Link to comment Share on other sites More sharing options...
AzNuggetBob Posted April 24, 2014 Share Posted April 24, 2014 The only thing I can think of to solve the problem is more pump power and or multi-jet nozzle. AzNuggetBob Quote Link to comment Share on other sites More sharing options...
Steel Pan Posted April 24, 2014 Author Share Posted April 24, 2014 Ya, I figured out about the nozzle being higher above the water would, and does,cause suction loss.I'm lookin' at layin' the nozzle/jet in the stream and usin' just the end of the hoseto move about and suck up material.We're kinda dancin' around my delema, but gettin' some good info out. When some one sets up a dredge and sluice, how long are the hose sectionsto and from the jet, that's really what I'm gettin' at? Don't know why I couldn't get to the point, right out the gate. I think they call it "Drain Bammage". Quote Link to comment Share on other sites More sharing options...
Steel Pan Posted April 24, 2014 Author Share Posted April 24, 2014 I just realized, there are a lot of views of this thread. "Location of jet"I wonder how many people thought it was about finding the lost Malasian flight.Well, as soon as I get this system operating the way I like, I'll look for that dang plane. My new bumper sticker,..."Dredge the Oceans" Quote Link to comment Share on other sites More sharing options...
Au Seeker Posted April 24, 2014 Share Posted April 24, 2014 My 4" and also 2 1/2" and 3" dredges have a 20' suction hose, 2" dredges usually have a 15' hose. Quote Link to comment Share on other sites More sharing options...
Au Seeker Posted April 24, 2014 Share Posted April 24, 2014 I just realized, there are a lot of views of this thread. "Location of jet"I wonder how many people thought it was about finding the lost Malasian flight.Well, as soon as I get this system operating the way I like, I'll look for that dang plane. My new bumper sticker,..."Dredge the Oceans" Went I first saw the title of this topic, I was going to move it to the ODDS N ENDS section, but then I read your topic!! Quote Link to comment Share on other sites More sharing options...
Steel Pan Posted April 24, 2014 Author Share Posted April 24, 2014 My 4" and also 2 1/2" and 3" dredges have a 20' suction hose, 2" dredges usually have a 15' hose. " how long are the hose sectionsto and from the jet, that's really what I'm gettin' at?"20ft each? Went I first saw the title of this topic, I was going to move it to the ODDS N ENDS section, but then I read your topic!! Life is so confusing sometimes,... Quote Link to comment Share on other sites More sharing options...
Au Seeker Posted April 24, 2014 Share Posted April 24, 2014 The high pressure hose is only about 5' to 6' long for a jet (your first picture), or only long enough to go from the pump to the jet (it could be longer, but no need), the suctions hoses are the length I mentioned above. For a suction nozzle, (your second and third pictures) the high pressure hose would be the same length as the suction hose. Quote Link to comment Share on other sites More sharing options...
Steel Pan Posted April 25, 2014 Author Share Posted April 25, 2014 (edited) My pressure line is actually about 600 ft long.(since it is a gravitational operating system)It's the suction hose length to the jet and the hose lengthfrom the jet to the crash box that are in question.That would be 2 dif hoses. 1. supply line2. line to sluice from nozzle/jet3. suction hoseLength of hoses 2 and 3 are in question.Suction.bmp Edited April 25, 2014 by Steel Pan Quote Link to comment Share on other sites More sharing options...
AzNuggetBob Posted April 25, 2014 Share Posted April 25, 2014 (edited) It may be better in the middle so to speak? (jet tube) never tried it? equal suction and pressure pushing? AzNuggetBob Edited April 25, 2014 by AzNuggetBob Quote Link to comment Share on other sites More sharing options...
Steel Pan Posted April 25, 2014 Author Share Posted April 25, 2014 That's what I'm thinkin', but the more hose I can use for suctionthe more movement I have with it. If I can have a 12' suction hose, that gives me more mobility. Quote Link to comment Share on other sites More sharing options...
Au Seeker Posted April 25, 2014 Share Posted April 25, 2014 In this picture... I don't see a "jet" like in your first picture shown above, I do see your 1 1/2" (?) pressure hose going to a Tee, and then to your suction nozzle, a 3"(?) suction hose from your suction nozzle to your crashbox/sluice, and you have about 2' of 3" hose on the nozzle end of your suction nozzle, is this the hose in question when you said..."3. suction hose"..., if so this hose just slows the material down, IMHO, because the friction inside the hose, I would not have the hose on the end of the nozzle, if you want to use the suction nozzle without bending over I would add a long metal handle to the suction nozzle so you can get the nozzle end into the material. I would keep your hose to your sluice at 20' or less, the shorter your hose the better your results will be, especially if there any lift/rise to your sluice.. Quote Link to comment Share on other sites More sharing options...
Au Seeker Posted April 25, 2014 Share Posted April 25, 2014 After posting the above, I also think you should try putting the suction nozzle at your sluice with a short piece of hose, like a jet would be placed, have 20' or less of suction hose off the nozzle into the stream. If you have another suction nozzle, or a jet you can use one in the middle of the hose as well, this setup is termed as a "midjet" and will greatly increase your performance. Quote Link to comment Share on other sites More sharing options...
Steel Pan Posted April 25, 2014 Author Share Posted April 25, 2014 (edited) Yes, number 3.What I'm tryin' to do is use the suction nozzle in place of a jet.Since I've never been around a dredge using a jet, I'm perplexedas to where you would normally place the jet in the line. The sluice is actually below the water level of the pool I'm dredging. Edited April 25, 2014 by Steel Pan Quote Link to comment Share on other sites More sharing options...
AzNuggetBob Posted April 25, 2014 Share Posted April 25, 2014 (edited) Something else Steel Pan a jet nozzle looses pressure with that 180 bend plain and simple. a hard right angle 90 is even worse. a jet tube with a long hose is better. Hey this is fun. AzNuggetBob Edited April 25, 2014 by AzNuggetBob Quote Link to comment Share on other sites More sharing options...
Steel Pan Posted April 25, 2014 Author Share Posted April 25, 2014 Something else Steel Pan a jet nozzle looses pressure with that 180 bend plain and simple. a right angle 90 is even worse. a jet tube with a long hose is better. AzNuggetBobYup, that's another thing.After i get the hose length figured out I'll cut and reweld the supply to a straight pipe. After posting the above, I also think you should try putting the suction nozzle at your sluice with a short piece of hose, like a jet would be placed, have 20' or less of suction hose off the nozzle into the stream. If you have another suction nozzle, or a jet you can use one in the middle of the hose as well, this setup is termed as a "midjet" and will greatly increase your performance.I tried the nozzle at aprox 3 ft from the crash box. It didn't work worth a squat.Apparently I didn't have a good water column in the hose to promote the suction. Quote Link to comment Share on other sites More sharing options...
Au Seeker Posted April 25, 2014 Share Posted April 25, 2014 Here's a picture of my 4" dredge, you can see the "jet" which is attached to the "flare" that is attached to the sluice, coming into the jet is the high pressure hose from the pump and the 4" suction hose with a metal tip at this suction end attached to the jet. As I described above you can use the suction nozzle setup the same and it will work if you have the correct high pressure coming into the suction nozzle, it will not make much difference where the suction nozzle is located, as long as the high pressure input is correct to create suction. Quote Link to comment Share on other sites More sharing options...
Steel Pan Posted April 25, 2014 Author Share Posted April 25, 2014 O.K., it would appear that it is the combo of the jetand the flare that makes the system work.Sooooo, if I put the nozzle back to the position of3 ft from the sluice I still need the flare for the system to work.Right? Quote Link to comment Share on other sites More sharing options...
Au Seeker Posted April 25, 2014 Share Posted April 25, 2014 No, you stated you have a crashbox, which will let the material slow down before entering the sluice, basically a flare replaces the crashbox, it lets the material spread out and thus slow down before entering the sluice. the way you have it setup in the picture above it should work or with the suction nozzle at the carshbox, it should work, I'm thinking you not getting enough pressure into the suction nozzle. How much fall do you have in your 300' of pressure line? Quote Link to comment Share on other sites More sharing options...
Steel Pan Posted April 25, 2014 Author Share Posted April 25, 2014 It's a 600 ft pressure line. 400 at 3" and 200 at 2".I reduce again to 1 1/2" at the manifold.I figure around 115 ft of drop and produce aprox57 psi. Aprox 2' of fall for every 1 psi.Marc Keene said I only need 30 psi to run the nozzle. Quote Link to comment Share on other sites More sharing options...
Au Seeker Posted April 25, 2014 Share Posted April 25, 2014 If you're getting 57 PSI you shouldn't have an issue no matter where you use the suction nozzle, and I agree that even with 30 PSI you should get decent suction, the only other factor would be volume.You may want to put a pressure gauge in your system just to see what pressure you're getting while static and running, if you have 50+ PSI static pressure, and it drops dramatically while running, the issue maybe volume and not pressure. Quote Link to comment Share on other sites More sharing options...
Steel Pan Posted April 25, 2014 Author Share Posted April 25, 2014 I'm glad you brought that up.I do want to put a pressure gauge on the lineout of curiosity if for nuthin else.A couple of years ago I was using a 1 1/2" nozzleand running off a 2" pressure line.When I changed to the 3" nozzle, I didn't have the volumeand that's when I went to the 3" main pressure line.If I did my math right, I have increased my volume seven fold.The system works just fine as it is, I'm just trying to figurea way where I don't have to handle the frickin' nozzle, and two (2) hoses all the time. Quote Link to comment Share on other sites More sharing options...
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