Saturday, Feb 20, 2010 at 11:09
PVC pipe or Poly pipe or steel pipe with a foot valve as the others have suggested......but I will add the following
The foot valve is simply a standard off the shelf plumbing fitting in either brass or poly.
It is simply a one way flow valve that allows water past it...by either a pump on the upstream side causing the suction action whereby it lifts off its
seat and whilst the pump is lifting it remains "suspended" and water passes around and above it........when the pump stops the suction it (the valve) drops down onto its
seat and seals off the column of water above it....this way the pump remains primed ready for the next lift.
the same action occurs if you plunge (free drop) the pipe and foot valve down a
bore on a length of rope and the downward motion pushes the valve upwards off its
seat ..the water passes around and above it and then when the plunging action is stopped the weight of water above the column seats the valve and the column of water remains in the tube or suction column above it....you pull it up get your water and repeat the process
plunging recovery does rely on some weight in the column so that when you drop in down into the water the valve is pushed up off its
seat........PVC and Poly pipe might be a light for that but using a brass foot valve (increased weight) can overcome this
Most
bore holes are cased with 4" or 100mm casing and so using say a length of 50 mm pipe you should nearly always be safe for physically fitting it down the hole
a one meter length of 50 mm PVC being rigid and therefore always straight is not likely to bind going down a narrower hole......but more likely to be damaged in the back of the ute over time which you may find out at the very time you wish to use it..........the fittings being glued on the end mean the over all dia is not more than say 60mm
a one meter length of Poly pipe a lot more robust but as it increases in length it is more likely to bow and therefore may bind down a narrower casing..its fittings are screwed on and the outside dia does increase to closer to 75 mm over all
The photo Mick put up is simply demonstrating the plunging action but with the water closer to the surface and a long length of poly available they are simply plunging the poly up and down and the water is flowing out..........no need for the rope and they are using their power to push the foot valve up and down by hanging onto the pipe
The way I see your question is you need something simple (no power required)......a rope (water depth recovery limited only by the length of rope) and a short length of pipe (1 or 2 m) with foot valve attached and a length of rope that can be secreted somewhere and retrived undamaged one day if needed.....a meter of 50 mm pipe is going to give you just under 2L water each time it is recovered
I carry a length of 50mm PVC (class 18 thick wall...= weight and strength) with the brass foot foot valve (for weight) ..two holes drilled across the top of the PVC column for the rope to pass through........slung carefully in the ute so all safe and ready for when I hope never to need it (I use the PVC because the over all dia with fittings is less than the poly / screwed fittings)
cheers
AnswerID:
405011
Follow Up By: equinox - Saturday, Feb 20, 2010 at 11:23
Saturday, Feb 20, 2010 at 11:23
Thanks for that. So a foot valve is basically a normal non-return valve, such as one you would find above a water pump to stop the head of water going back through the pump.
I would imagine you could modify the spring of the valve to reduce the pressure on it.
Cheers
FollowupID:
674721
Follow Up By: Member - bungarra (WA) - Saturday, Feb 20, 2010 at 11:33
Saturday, Feb 20, 2010 at 11:33
Yes exactly...a one way valve....
the simplest foot valve has no spring just a a flat plate that sits on a leather or neoprene seal.....the water pushes past it and when that action stops it is weighted back down ono the seal..........no need for any spring....keep it simple..mechanical..and it will always function..usually the brass ones are this design..that is another reason why I use a brass one
the poly ones usually have a ball and spring...that is another thing that can go wrong...but they have a purpose in that they can operate in all positions
the brass one must hang vertically to work..which is obviously what is going to happen down a
bore
FollowupID:
674724
Follow Up By: Member - Amy G (QLD) - Saturday, Feb 20, 2010 at 11:36
Saturday, Feb 20, 2010 at 11:36
Just some info on monitoring bores out here in QLD- they are cased with PVC pipe that has around 53mm internal diameter. So 50mm poly pipe should be fine if want to extract water (of course, in urban areas they are padlocked!). As far as I'm aware, in SA they are the same (we used 50mm pumps to sample, and again they were always locked).
FollowupID:
674725