Correct Spraying Rate on a small sprayer

[DavidHammond123]

To be honest I can't imagine any sensible person to realistically expect those sprayers to last 5 years nor would they be the type of operators that would be working at an expected 10% error. Their own miscalculations and misunderstanding of how to calculate in the first place will be give more than 10% error.
Might sound harsh but loads of posts on here of professional farmers asking how much chemical to put in a sprayer to do two fields. No idea how much water the sprayer holds, no idea of sprayer output or even a realisation it can vary or matter, no idea of tractor speed and no more idea of area of the fields other than some random thing like "well I put two bags on the first one each year and the other is about three rounds more but gives less bales most years"

Those cheap sprayers are plenty accurate enough and will do a good job as they are as long as you know how to use one. Nothing particularly difficult about it either, in your own words you have found a solution for a problem that doesn't really exist.

Go and build me a cheap PU realtime monitor for in bottle pasteurising with multiple senders wifi or bluetooth linked to a central datalogger/monitoring device. Make sure it has alarms that operate on various settings, ie. 60PU to 1000PU.
PU = (time in minutes) x 1.393 exp(T-60), where T is the temperature in Celsius.

Yes the maths isn't difficult for sprayer calculations especially with the information provided by the sprayer/nozzle manufacturers, I guess an advantage of an app is it could automate the maths and reduce human error. But yeah I'm still not sure if my solution would be valuable to farmers with these sprayers.

Those PU monitors are interesting, the closest thing I've done to dairy before is feeder wagons so I hadn't heard of them before. It looks like they would require quite a bit of mechanical design to get working correctly and to endure the temperatures.

 

[DavidHammond123]

You may need to find out who buys these sprayers and why. I thought(may be wrong here) anyone selling cereals through a quality scheme needed a certificate on the sprayer which included a working rate controler so anybody buying one in your link is only going to spray a bit of grass and buying that sprayer on price.

That's a good point, you can probably tell but I don't come from a farming background so I don't know much about the 'real world' of farming. One of my big worries is that these are cheap sprayers so farmers buying them might not want to spend more on a monitor/controller if they don't see the need for one.

 

[Boysground]

That is exactly what @Boysground is describing

Going back even further. When I was on placement at college (1990) the farm had a DDB self propelled with berthoud kit on it. The pump was a true ground drive. To change the rate you altered a bolt on the pump which changed the output of it. We did lots of changes and once you knew where to set it was spot on irrespective of speed. Again such a simple system. I just can’t remember what the pump was called.

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[Boysground]

You may need to find out who buys these sprayers and why. I thought(may be wrong here) anyone selling cereals through a quality scheme needed a certificate on the sprayer which included a working rate controler so anybody buying one in your link is only going to spray a bit of grass and buying that sprayer on price.

I just thought of this walking my dogs, PA1 and 2, sprayer mot. Any farmer spraying properly and legally should be able to set up the rate manually with nothing more than a jug and watch.

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[Boysground]

Yes the maths isn't difficult for sprayer calculations especially with the information provided by the sprayer/nozzle manufacturers, I guess an advantage of an app is it could automate the maths and reduce human error. But yeah I'm still not sure if my solution would be valuable to farmers with these sprayers.

Those PU monitors are interesting, the closest thing I've done to dairy before is feeder wagons so I hadn't heard of them before. It looks like they would require quite a bit of mechanical design to get working correctly and to endure the temperatures.

I think you may find more opportunity with the feeder wagons. The software on mine is rubbish. The next one I buy will almost certainly come without a computer fitted and I will add Cow Connect.

If you can complete with them on price and usability there’s a market there.

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[oakleaf]

Going back even further. When I was on placement at college (1990) the farm had a DDB self propelled with berthoud kit on it. The pump was a true ground drive. To change the rate you altered a bolt on the pump which changed the output of it. We did lots of changes and once you knew where to set it was spot on irrespective of speed. Again such a simple system. I just can’t remember what the pump was called.

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Berthoud still offer a ground drive sprayer.
Model designation DPA.
I've had one for many years and get on great with it
lnfinitely variable pump from 50 to 700 litres/ha which is spot on every time.

 

[2wheels]

I once had a Berthoud sprayer with a piston pump (no diaphragms) as long as you stayed in the same gear the speed could be altered with the revs and the rate would stay spot on, it really was very good. Simple and never caused problems. I always wondered why others manufacturers didn’t do something similar.

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our old sprayer with a diaphram pump was the same.

 

[Exfarmer]

Going back even further. When I was on placement at college (1990) the farm had a DDB self propelled with berthoud kit on it. The pump was a true ground drive. To change the rate you altered a bolt on the pump which changed the output of it. We did lots of changes and once you knew where to set it was spot on irrespective of speed. Again such a simple system. I just can’t remember what the pump was called.

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Positive displacement pump, they are the only pumps which will give a totally true rate without a fancy compensating system. But most will stay within bounds if you do not exceed 20% speed error. Of course these need an operator who does not wish to ignore everything while he is on facebook since exceeding the speed to much will give some dramatic pressures in the system

 

[Boysground]

Positive displacement pump, they are the only pumps which will give a totally true rate without a fancy compensating system. But most will stay within bounds if you do not exceed 20% speed error. Of course these need an operator who does not wish to ignore everything while he is on facebook since exceeding the speed to much will give some dramatic pressures in the system

It was a great system, but didn’t use it to put my foot down and cover more acres. With my often quite steep chalk banks it meant the tractor could slow going uphill and over run a little going down and the rate would stay spot on. Had it on a 1200l mounted sprayer with 20/21 m booms.Did a lot of work with it.

Have a Knight now, all isobus to the tractor and section control which is great. I really enjoy using it but there is so much more potential for things to not work.

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[Exfarmer]

It was a great system, but didn’t use it to put my foot down and cover more acres. With my often quite steep chalk banks it meant the tractor could slow going uphill and over run a little going down and the rate would stay spot on. Had it on a 1200l mounted sprayer with 20/21 m booms.Did a lot of work with it.

Have a Knight now, all isobus to the tractor and section control which is great. I really enjoy using it but there is so much more potential for things to not work.

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How did it work on a mounted sprayer, my neighbour had a trailed 24 m and I know he loved it. I sonetimes wished I had one spraying fields of potatoes , when sometimes you had to drop a gear to avoid stalling, ( I could not afford the all singing and dancing radar computer controller)

 

[Boysground]

How did it work on a mounted sprayer, my neighbour had a trailed 24 m and I know he loved it. I sonetimes wished I had one spraying fields of potatoes , when sometimes you had to drop a gear to avoid stalling, ( I could not afford the all singing and dancing radar computer controller)

Tbh I’m not sure how exactly the pump worked. I guess there was always a know amount of liquid from the pump for each revolution of the pto. If the engine revs changed output would accordingly.

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[Boysground]

They still do it @Exfarmer

BERTHOUD - Specialist in agricultural and wine-growing spraying

BERTHOUD is a French specialist manufacturer of sprayers for treating agricultural plots and vines.

www.berthoud.co.uk

It’s the dpm auto regulator. Google wins again

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[DavidHammond123]

If you want to be accurate with the sprayer it’s better to do a jug test on at lest 1 nozzle from each section rather than rely on information tables. Nozzles can either wear of gradually block depending on products being sprayed. Measure the flow per minute at standard PTO speed. This is the most important bit of the calibration process along with nozzle spacing and forward speed.

How often would you have to re-measure the flow from the nozzle tips?
How often do you replace nozzle tips because of wear?

I'm surprised they can wear down so much that they go out of spec just from liquid going through them, I guess the chemicals are harsh.

 

[Muddyroads]

How often would you have to re-measure the flow from the nozzle tips?
How often do you replace nozzle tips because of wear?

I'm surprised they can wear down so much that they go out of spec just from liquid going through them, I guess the chemicals are harsh.

The wear will be down to the products used. Some are dissolvable powders which will be more abrasive than liquids. This is the reason for the development of ceramic nozzles. Frequency of testing will be down to the diligence of the operator.

 

[2wheels]

The wear will be down to the products used. Some are dissolvable powders which will be more abrasive than liquids. This is the reason for the development of ceramic nozzles. Frequency of testing will be down to the diligence of the operator.

covered thousands of acres with lechler id nozzles with the ceramic tips. a lot of abrasive suspension and powders materials. never had to replace one for being out of spec. broke some though.

 

[Exfarmer]

How often would you have to re-measure the flow from the nozzle tips?
How often do you replace nozzle tips because of wear?

I'm surprised they can wear down so much that they go out of spec just from liquid going through them, I guess the chemicals are harsh.

Most of these small sprayers do so little work, it is unlikely that they will ever wear out one set of nozzles unless spraying some highly abrasive mixes, ( and I cant even think of one) . The most likely reason any will run out of pattern is through the use of inappropriate cleaning tools, or through coming into contact with the ground etc.
Provided they are tested once a year or any time a nozzle characteristics change, it is unlikely they will ever need changing.
The main issues will be, only ever using clean water in them and being aware of some products which may cause blocking of the nozzles, often by leaving mixed product in tank for some time.

 

[whiddy]

Had a MBTrac with Evrard dpa pump, set the stroke on the pump, then what ever speed you liked in that gear.
you also had to change return disc's in the manifold for each section, so that it would return the correct amount back to the tank, as you turned each section off.

 

[Flatlander]

The first sprayer I bought here in Canada was a prototype built locally by Valmar industries. It had been used by a local chemical dealer for spraying potatoes. After a few year it was sold to the man I got it from but he fried the controller some how. I bought a replacement but could never get it to work. Previous owner used vice grips to restrict the return line to set pressure then just drive about 10 mph lol. Was a joke. Ended up putting a micro trak unit on it Gps speed sensor,flow meter and butterfly valve. Amazingly accurate best 1600$ spent ever. Save me a pile of money over the years. Can still be bought now for similar money.