CapstanAG PinPoint III ENVELOP, Руководство оператора

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TM
Troubleshooting
Technical Bulletin
This technical bulletin was originally produced July 11, 2001. The latest revision to this bulletin was
made November 1, 2017.
Spray Skips from Poor Pulse Blending
Over the years, CapstanAG field engineers have received many questions about Blended Pulse
™
spraying and its potential for causing skips in the field. In rare instances, skipping has been
documented in the field. This technical bulletin is intended to explain pulse blending, and the
techniques used to provide optimum spray coverage and to prevent skipping.
What is Blended Pulse
™
spraying? Each nozzle in a Blended Pulse
™
spray system emits 19 spray
pulses per second. Adjacent nozzles have alternate timing. The alternating pulses, the overlapping
spray patterns, and the natural dispersing of droplets, blend together to provide consistent coverage
of the target.
What makes the pulses blend? Below is an illustration of what a blended pulse spray pattern
might look like if it were sprayed upon a flat surface. This spray pattern is similar to a #8 size flat fan
spray tip (with a 110° fan angle) that is spraying 5 GPA at 15 mph with a 50 psi boom pressure. The
nozzles are 20 in apart. Each tip is rotated 12.5° to prevent pattern interference between nozzles. The
minimum boom height is 21 in above the spray target.
Figure 38: 11008 Flat Fan Tip
In this example, each nozzle sprays 1/3 of the time, but adjacent nozzles alternate and overlap to
fill in areas between the nozzles. As the sprayer increases speed, rate, or boom height, the pulses
become wider, this provides additional overlap, better pulse blending, and increased spray coverage.
As the sprayer decreases speed or rate, skips may begin to appear. For this example, a smaller tip
size would be recommended if slower speeds are desired.
Pattern width and natural droplet dispersion are not shown in the diagram. These factors help to
smooth out the pulses and fill in skips. The amount of droplet dispersion depends upon the style of
tip being used. For example, low-drift tips typically emit large droplets and provide minimal droplet
dispersion.
What causes skipping? Below is the same illustration from the previous page except that 80°
fan angle tips are used rather than 110° tips. In this case, the 21 in boom height does not provide
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2021 Capstan Ag Systems, Inc.
114
PinPoint
™
III ENVELOP