Water Winch Used To Keep Draft Depth In Portable Tanks

Water Winch Used To Keep Draft Depth In Portable Tanks

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Captain Defiance, Ohio, Fire Department

A primary problem that arises when two or more portable tanks are used to supply the fireground pumper in a tanker shuttle operation is maintaining an adequate water level in the tank from which the pumper is drafting.

Although siphoning through hard suction hose or tubes made of plastic pipe and using portable pumps to transfer water from the auxiliary portable tanks to the primary tank are useful ways of maintaining the water level for drafting, they have disadvantages.

While teaching rural water supply courses at county and regional schools during the last several years in 33 counties of northwestern Ohio, I coneluded that there must be a better way. Therefore, we developed what we call a “water winch” that can transfer as much as 260 gpm from an auxiliary tank to the primary tank.

Material needed

The following are parts needed to manufacture the water winch:

1 – 4 X 2 1/2-inch std. wt. weld reducer

1 – 1 1/4 X 1/2-inch copper solder fitting reducer

1 – 1/2 X 1/4-inch copper solder fitting reducer

1 – Female end of a 1-inch Bar-Way coupling

1 – 2 1/2-inch male coupling thread (cut thread off old hose coupling)

3 – Metal struts (to hold Bar-Way coupling in the weld reducer)

The water winch is attached to a 10-foot section of 2 1/2-inch hard suction hose. A 1-inch booster or 1 1/2-inch hand line is attached to the water winch. The size of hose depends on gpm needed to be transferred from the auxiliary tank.

As water is forced through the water winch’s orifice, a negative pressure is created (about 10 to 15 in Hg) at its base. Water from the auxiliary portable tank enters the water winch and flows through the attached hard suction hose into the primary tank. The water used to operate the water winch also goes into the primary tank, from which it was drawn.

Using a 1-inch, 200-foot, booster line with a pump pressure of 150 psi, the water winch requires a flow of 31 to 33 gpm to transfer 170 to 180 gpm. Total flow from a 10-foot, 2 1/2-inch hard suction hose is 200 to 215 gpm.

With a 1 X 1 1/2-inch reducer, a 50-foot section of 1 1/2-inch hose is used with a pump pressure of 125 psi.

The water winch requires 43 to 45 gpm to transfer 200 to 215 gpm. Total flow from the hard suction hose is about 240 to 260 gpm.

Some advantages of the water winch are as follows:

1. Water can be drawn down within inches in the auxiliary tank even though whirlpools are created.
2. The pump operator controls the transfer flow rate and can stop the flow if necessary.
3. Small in size; easy to store in compartment.
4. Water can circulate through the pump when fire lines are closed.
5. Water can be transferred effectively even when the tanks are at different elevations.
6. Ease of operation; just drop end into auxiliary tank and charge the line.

I have demonstrated the use of the 3 or 4-inch plastic siphon tubes. Although this method is effective, there are some disadvantages:

1. Water can be drafted from the primary tank faster than siphon tubes can refill it from auxiliary tanks.
2. As the water levels in the tanks tend to equalize, the flow rate of siphoned water diminishes.
3. If the water levels in auxiliary tanks are below that in the primary tank, a reverse siphon will occur unless the siphoning tubes are removed.
4. If portable tanks are at different elevations, siphon tubes are less effective unless the auxiliary tanks are at the upper elevation.
5. Fire fighters usually get wet placing siphon tubes in operation.

At the past several schools I’ve instructed, the water winch has been more successful than plastic siphon tubes in transferring portable water.