Patternator Testing - 2010

The three patternators were tested to determine if there was any significant difference between the various designs. Our vineyard sprayer used for the testing is a three point hitch Berthoud MGP 360 with torex nozzles purchased in 1975. The tractor utilized to operate the sprayer is an Oliver Super 55. Tractor PTO was set to 440 RPM using an ES 332 laser tachometer for all tests. At this RPM the sprayer pressure was set at 70 PSI. Water with no additives was used in the sprayer for all tests. The sprayer nozzles were open for one minute during all tests. Testing was also done with two sets of sprayer discs. One set were Berthoud Saphirex 10 discs that came with the sprayer. The disc orifice diameter was checked with a digital caliper accurate to 0.0005 inches. The Berthoud Saphirex 10 discs had an orifice diameter of 0.033 inches. A new set of TeeJet D1.5 hardened stainless steel discs was also used. The orifice diameter of these discs is listed as 0.036 inches. Measurement with a digital caliper found the orifice diameter to be 0.032 inches.

A Berthoud 360 MPG sprayer has a total of 10 nozzles with five on each side. When spraying in our vineyard, once the vines have reached the top wire at 6 feet, only three nozzles per side are opened. The top and bottom nozzles are not utilized. For all testing of the patternators, the same setup was used. Only the nozzles on the right side of the sprayer were utilized during testing.

The amount of water captured by each of the three patternators and their seven panels was tested. The mid-line of the sprayer was positioned 4.5 feet from the patternator surface. When spraying in our 9 foot wide rows, the mid line of the sprayer is 4.5 feet from the trellis on either side. The height of the sprayer remained constant through all testing. For each test the tractor was positioned with the sprayer nozzles in line with the leading edge of the patternator. This position maximized the collection of sprayer effluent. All patternators received a one minute trial run before any measurements were made. This trial run was made to insure all surfaces had been exposed to the spray and any water adhesion due to surface tension had occurred. With no trial run, the initial test would have slightly lower amounts of water collected in the containers. Three replicates were run for each test.

Statistical analysis was performed between the same panel on the three different patternators. Panel #1 is positioned to collect spray from one to two feet off the ground. Panel #2 is positioned to collect spray from two to three feet off the ground and so forth. The top panel is #7, which collects spray from seven to eight feet off the ground.

Statistical analysis was performed on the data using the VasserStats website. A one-way analysis of variance (ANOVA) for independent samples with a Tukey's HSD test was selected.