Jet Siphon or Linking Porta Tanks Together?

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Permalink Reply by David Klotz on June 13, 2008 at 4:03pm

We use them on our porta tanks. I have only been a member for 5 years now and only once have we setup a pond operation for a fire and we used them for that as well as every time we have trained on pond operations. Here is a link to the guideline we use and follow for pond operations.
http://www.bcfirechiefs.org/Guidelines/tender_guideline.htm

Permalink Reply by Wayne Knott on April 13, 2009 at 2:39pm

Lets go back to what is our FIRE FLOW GOING to BE???? 250 GPM?? 500GPM?? 750GPM??? what sort of time is a 2500 gallon tank goin to give you (YOU DO THE MATH!!) NOT MUCH ON THE LARGER FLOWS. Is it a BARN ,SAWMILL, YOU NAME IT! Whats going to be your NFF???? What formula are going use?? IOWA, NFA, etc.......Google earth some of your "BIG ONES" whats over the fence out of sight for water, HAS ANY BODY DONE THIS YET?? it a real kick in the head for those when you start dropping 2 or 3 even 4 fold-a-tanks and or "BAGS" and folks haven't a clew what your up to!!! Wisky -Tango-Foxtrot!!!! is going on???? KEEP IT FLOWIN AND GOIN Wayne

Permalink Reply by Jeffery A. Hartle on May 3, 2009 at 11:39pm

I've worked around folding tanks (large square frames) and self-supporting tanks (round, no frame) for 30 years. Folding tanks can be linked together easily, while self-supporting tanks are difficult to link together. There are several ways to link folding tanks together.

METHOD 1

Early in my career, we made siphons out of 4" PVC. They looked like inch worms, made out of 90 degree elbow from horizontal to vertical, a straight piece of pipe tall enough to reach from the bottom of the tank and clear the frame, a second 90 degree elbow joined to a 24" piece of pipe, linked to a third 90 degree elbow joining a straight piece of pipe (similar length to first piece) reaching down to the bottom of the tank, with a fourth 90 degree elbow. Fill the pipe with water, put in two plugs (one on each side) then place the siphon between two tanks. Remove the cap from the full tank first, then remove the cap from the low tank. Water will equalize between tanks. DOWNSIDE--water will always equalize between tanks! Sometimes, water will flow from the drafting tank to the dumping tanks, like when a tank lining develops a split or tear. The only way to stop the flow is to lift the siphon and break the flow of water. DOWNSIDE--siphons take up a lot of space and have only one use.

METHOD 2

We made our own jet siphons by purchasing a threaded fitting sized to fit the engine's hard suction hose. We then welded in a three-sided piece that held a 1" bushing in the center of the threaded fitting. We installed a 1" pipe in the bushing with a 1" coupling installed to project the 1" pipe about 4" inside the hard-suction hose. On the other end (protuding outside the hard suction), we installed a 90 degree elbow and a section of pipe that connected to a 1.5" NST hose coupling. We could then attach a section of fire hose to flow through the 1" pipe creating the venturi inside the hard suction. UPSIDE--We could create a jet siphon for each engine (some with 4" hard suction, some with 4.5", some with 5", and some with 6"!) DOWNSIDE--Again, a single-purpose tool, requires some mechanical ability.

METHOD 3

Purchase a low-level drafting strainer with jet siphon attachment. Place one on each engine. Our drafting engine always places one on the end of the drafting hard suction with 1.75" hose attached. UPSIDE--When the pump primer fails, as it will if you believe in Murphy (!), charge the 1.75" hose and ram water up the hard suction! Place one on a 10' section of hard suction and you can use the jet siphon to move water from the dump tank to the draft tank. Multiple uses! DOWNSIDE--May cost some money, but it's almost idiot proof, IMHO.

I've had great success with jet siphons. They are under the complete control of the pump operator, can be turned on and off as needed, and the process can be repeated between numerous drop tanks. I've seen four tanks on the ground and connected together with jet siphons. Folding tanks can be added when a tanker pulls into the scene and finds the tanks on the ground full of water already. When additional fireflow is needed between tanks, a second engine can be positioned to pump the jet siphons. (Remember that any water used to pump the siphons can be continuously recycled through the dump tank system.) I recommend placing folding tanks on the ground in a diamond shape with the point at the pump panel, rather than squared up with the pumping engine. This takes a little more room beside the drafting engine, but leaves more walking room beside the engine to retrieve equipment during operations.

Anyone have other ideas? I'm always interested in improving our operations.

Jeff

Permalink Reply by Joe Weinert on May 17, 2009 at 9:50pm

In our area we use jet siphons. We find this easy and fast to deploy even though we have never tired the linking of the tanks. When at larger fires were we are moving a lot of water and dont want to tie up a discharge by using a siphon we have another engine come in and just run the siphon. It doesnt take flow or gpm from the pump to the handlines in use. It works great because on larger fires we need people and a lot of the times there are pumpers just sitting on the side of the road not being used. We tested this theory at a tanker operations drill where we had pumpers filling tankers from dump tanks then having the tankers dump back into the tanks to test different ways to fill tankers (i.e. hose sizes, connection types. ect). We used the jet from the pumper filling the tanker and using the jet by a different pumper and using the other pumper kept the tanks we need full and filled the tankers faster. It works great for us, its something you may want to try.