NURSE TANK CONNECTION- Formerly, we made recommendations regarding connections from the tank to the Equaply® system, those recommendations have become requirements. For high flow rates, the use of dual tanks and dual lines is necessary, particularly during cold weather. To maximize flow rates we recommend that you acquire tanks dedicated to your use. See our section on tanks for other details. Unlike Exactrix, our system doesn't need bottom outlet tanks.
VAPOR SEPARATOR- The one and only reason for heat exchangers with ammonia systems is to cool the anhydrous below its boiling point. In systems without pumps, vapor makes most flow meters inaccurate. Most pumped systems such as Equaply® vapor lock when a gas phase is present. Once pressure has been increased by the pump, the anhydrous is much below its boiling point.
A hydrastat protects against over pressurization by solar heating of a standing, charged system.
PUMP- The pump assembly is arguably the most important part of our system. We use a Hypro centrifugal pump because it does not have surges like piston pumps. A hydraulic motor drives our pump. A solenoid operated hydraulic valve turns the pump motor on and off for each row.
Perhaps the most important reason for a pump is equal distribution. The pump keeps anhydrous as a liquid until it can be split at manifolds. To understand what happens with a mixed liquid/gas stream it helps to have transparent pipes. The Red Ball rotameters in our prototypes were those clear pipes. During startups and when there were malfunctions one could see the vapor as it went through the rotameters. When vapor first appeared in the system it would exit in the first rotameter in a bank of four. Increasing amounts of vapor then reached subsequent rotameters. Vapor takes the easiest path. For example, if there is a circular manifold on a toolbar which tilts down to the left on a hillside, vapor will tend to go out of hose barbs which are up and to the right, liquid going down to the left.
For custom applicators, the most important reason for a pump is the ability to apply at full rate when it's cold. Conventional systems often slow down during late Fall and early Spring.
FLOW MEASUREMENT AND CONTROL- Equaply® units have as standard, a Hiniker flow sensor and KZCO servo valve. Signals from the flow sensor go to a controller which then operates the servo valve. With our system the flow sensor has maximum accuracy because it sees only liquid. Equaply® units can interface to AgLeader Insight and John Deere Greenstar.
MANIFOLDS & ORIFICES- After the servo valve, we split flow at one or more manifolds. Each manifold is controlled by an electrically operated valve. Electric valves allow swath control, turning off one or more sections.
The range of rates possible with a given set of orifices is not great as we would like. This is particularly true with large seasonal temperature differences. Nurse tank pressure can easily range from 50 psig to 150 psig. Fortunately the TeeJet® orifices in the Equaply® system are quickly changed. If large rate variations are necessary as with custom application, we can widen the range using Impellione manifolds.
Side dress applications typically skip a row; a 16 row toolbar will have 15 knives. In that instance, we can supply orifices for the two end rows that have 0.5, 1.5 or 2 times the rate of interior rows.
FLOW VERIFICATION- The Equaply® system uses a pressure gauge per row to verify row to row equality of flow. When upstream pressure and downstream pressures are the same with orifices of equal size, flows are the same. Pressure gages connect downstream from the knife orifices. They are mounted on a gauge tree or panel between the tractor cab and the toolbar.
One can tell at a glance if a knife is plugged (high pressure) or an orifice is plugged (low pressure).
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