Nurse Tank connection- Previously, we made recommendations specifying 1.5" hose and connections from the nurse tank to our Equaply® system. Those recommendations have become requirements. For high flow rates, the use of dual tanks with 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 details. Unlike Exactrix, our system does not 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 flow meters inaccurate and pumps vapor lock. But heat exchangers have a problem with the coolant line unbalancing flow among the knives. Also, capacity of heat exchangers is greatly reduced in cold weather. Our Liquimatic® vapor separator solves these problems, allowing high flow even in cold weather.
A hydrostat protects against over pressurization by solar heating of a standing, charged system.
Pump-The pump assembly is the second 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 early 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 of 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® Custom units have as standard, a MicroTrak flow sensor and a KZCO "Q-ball" servo valve. The "Q-ball", available only from KZCO, provides sensitive control at lower rates than are possible with conventional ball valves. The flow sensor signals the controller which then operates the servo valve. With our system the flow sensor has maximum accuracy because it sees only liquid.
Manifolds & Orifices- After the servo valve, we split flow at one or more manifolds. Each manifold is controlled by an electrically operated valve. Multiple manifolds with 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. Often, we widen the range using Impellicone 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 same size orifices, 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).
Our "Equarow" electronic row monitor and system is now a functioning prototype and we hope to introduce it late Fall 2011.
ACCESSORIES- The "Yield+" chemical injector is now in limited production, available this Fall. The Yield+ is capable of high pressure injection of N-Serve into the anhydrous stream. Other injectors for N-Serve can't be used with Equaply® Custom systems because they do not provide high enough pressures. For those desiring to inject liquid fertilizer with anhydrous, we have a companion unit with a centrifugal pump.