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Tim McCulla wrote:

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Yea, just looking at the specs - you know they are some bucks.

Do you Know anybody using them?

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No, but I was the first roof cleaner I know to use many pumps. A roof cleaning pump NEEDS more pressure then what we have now, for our roof cleaning brothers up  north who must shoot 3 story 10/12 pitch roofs from a ladder on a cold, windy day! My 1 inch Hastelloy Air Diapraghm pump will take 125 psi all day long, and is scary fast with a big 22 CFM compressor for florida roofs. But I am NEVER "satisfied", and always looking for the best roof cleaning pumps. I am sure these are in the 2 thousand dollar range list price, but people spend 4 thousand on a pressure washer skid to clean 50 dollar driveways Why NOT spend 2 grand on a REAL roof cleaning pump that will enable them to clean roofs others run away from ?

 

We sure do need a pump with more pressure up here Chris, I am going to put two fatboys together like Mike Sullivan does. Get ready for the call BOb.

Roof Cleaning Long Island N.Y 516-763-4108 wrote:

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We sure do need a pump with more pressure up here Chris, I am going to put two fatboys together like Mike Sullivan does. Get ready for the call BOb.

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2 Fat Boys together will give more GPM,. what u really need is more Pressure!

Roof Cleaning Long Island N.Y 516-763-4108 wrote:

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Thanks Chris, I must have mis understood. I thought I would get more pressure and shoot further?

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NO! Delevan Fat Boy Pumps are positive displacement pumps. ONLY Centrifugal Pumps  have an additive pressure effect when stacked in SERIES, one pump feeding the other.
Pumps in parallel like side by side Fat Boys double flow, pressure remains the same!

 

Roof Cleaning Long Island N.Y 516-763-4108 wrote:

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Thanks again...........

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Read this, and you can see that added flow can sometimes be beneficial, IF adequate PRESSURE is maintained.

Hydraulic tree sprayers

Hydraulic (liquid) sprayers are used for all sizes of trees. Tree sprayers are available as trailer models to be towed or skid-mounted models for use on pickup trucks or other vehicles.

They vary in size from a 2.5 to 10-gpm pumps and 2 to 20-hp engine Low Volume Low Pressure (LVLP) units used by homeowners to 15 to 60-gpm pumps and and 35 to 65-HP engine High Volume High Pressure (HVHP) machines used by municipalities, institutions, or custom-spray operators like Horizon Forestry™.

Tank sizes vary from 10 gallons up to 1,000 gallons. Some of the large trailer units can be powered from a tractor power-take-off shaft. Between these extremes there is a wide range of sizes and options.

The hydraulic sprayer uses large volumes of water and high pressure. The taller the tree, the higher the required pressure. However, since higher pressures tend to produce smaller droplets, larger orifices must be used to offset this effect. Droplets must be relatively large to have sufficient momentum to carry to the tree tops and to adhere to the surfaces. These factors are documented in the table of guidelines below.

Minimum Hydraulic Sprayer Requirements* for various tree heights;

Trees up to 15', 3-gpm, 400-psi, (LVLP)
Trees up to 25', 5-gpm, 400-psi, (LVLP)
Trees 20' - 30', 10-gpm, 400-psi, (LVLP)
Trees 30' - 45', 15-gpm, 400-psi, (HVLP)
Trees 35' - 50', 20-gpm, 400-psi, (HVLP)
Trees 45' - 65', 20-gpm, 800-psi, (HVHP)
Trees 65' - 85', 35-gpm, 800-psi, (HVHP)
Trees 85' - 115', 60-gpm, 800-psi, (HVHP)

* Pennsylvania State University College of Agriculture

As the tree height increases, the spray angle at the nozzle is decreased to concentrate the pressure in the spray stream. In spraying tall trees, a solid stream may be used with most of the liquid breakup being produced by the resistance of the air after the liquid leaves the gun.

Nearly all hydraulic tree sprayers use a hand-held gun. For short trees and shrubs a multiple-outlet gun may be used but the single-outlet gun with a pistol-grip valve is the most common. Many applicators use a variable discharge-angle gun; with a twist of the handle the spray angle can be controlled from a wide angle for short trees and shrubs to a solid stream for tall trees.

The working pressure at the gun is very important for satisfactory operation. Often the gun is a considerable distance from the pump. Runs of 200 feet or more are common where the sprayer must be parked away from the tree being treated, i.e. street parking when spraying a backyard tree for a homeowner. Whenever liquid flows through a hose, friction loss is unavoidable. However, this loss can be minimized by choosing the proper diameter hose for the desired flow rate. Of course the choice is a compromise among friction loss, cost, and handling ease (size and weight of hose with water).

Since friction (pressure) loss is directly proportional to length, you can extend the information to any length, i.e. a 100-foot hose has twice the loss of a 50-foot hose. Select hose size based on flow of the gun or other delivery means being used, not the rated pump capacity. It is interesting to note that for a given flow, a change of one commercial hose size has a big effect on friction.

Additional pressure losses occur at fittings, valves, and turns. To check pressure at a gun, simply 'tee' a gauge into the line at the gun and read pressure while spraying at the desired rate. No friction loss occurs when the gun is off because there is no flow present. As you start spraying, you may observe a quick pressure drop at the gun; this drop is the friction loss in the hose as the flow initiates.

Generally, coverage by a hydraulic sprayer is relatively good with a high volume of water; if there are problem areas, they are usually in the tops of very tall trees. Height of effective coverage can be increased by using elevated truck-mounted platforms, gun extensions, or ladders.

The spray mix is relatively dilute and therefore relatively safe. Although the droplets are larger and more resistant to drift than those from an air-blast sprayer, drift can still be a serious problem. To insure adequate coverage, trees are usually sprayed to the point of runoff.