Trailed vs Self Propelled Sprayer

[Brisel]

Ok. I don't know what they used to be like but they are well respected around here now and look well made. Are you going to Cereals to have a look at potential machines?

 

[Clive]

Ok. I don't know what they used to be like but they are well respected around here now and look well made. Are you going to Cereals to have a look at potential machines?

I'm at cereals but not really primarily to look at machines, prefer demo's to make decisions

Will get demo's of the 2 likely candidates at some point this year, also need to make a decision re boom width at some point, if we went trailed I would go to 36m I think to offset the fact I would stay on 710 tyres all year round

I wouldn't consider most other brands of trailed purely on the basis of lack of any prospect in residual value - you may as well set fire to your capital as buy some brands of farm machinery unless you intend to keep it for ever

 

[Mdt]

@Clive if thinking of a 36m setup what tank size are you thinking of?

 

[Clive]

@Clive if thinking of a 36m setup what tank size are you thinking of?

we are at 4000L at the moment - that's 100ac on a fill so dont see much need for bigger really, with wider booms I would be very conscious of the weight

 

[Feldspar]

How much variation is there from one liquid fert nozzle to the next? Are we talking 5% or more / less?

 

[db9go]

How much variation is there from one liquid fert nozzle to the next? Are we talking 5% or more / less?

What do you mean on the same machine if so using BFS dribble bars nothing between each one

 

[Feldspar]

What do you mean on the same machine if so using BFS dribble bars nothing between each one

Yup, from one nozzle / bar to the next down the boom.

 

[Daniel]

Yup, from one nozzle / bar to the next down the boom.

That isn't how gases and liquids flow?

If you have 30 metres of water pipe and drill 10 identical size holes along the length, stop the end up and pump water in at 3 bar then the flow rate will be the same out of each hole after the first couple of seconds.

Like wise a huge extractor fan at the end of shed will draw an equal amount of air through 10 equally sized inlets.

 

[Feldspar]

That isn't how gases and liquids flow?

If you have 30 metres of water pipe and drill 10 identical size holes along the length, stop the end up and pump water in at 3 bar then the flow rate will be the same out of each hole after the first couple of seconds.

Like wise a huge extractor fan at the end of shed will draw an equal amount of air through 10 equally sized inlets.

That's the point though, isn't it; are they they the same sized hole? If the flow was always identical through spray nozzles (same principle) then why is it part of the sprayer MOT?

 

[Daniel]

Because nozzles wear at different rates? They all give the same flow out of the packet.

 

[Feldspar]

Because nozzles wear at different rates? They all give the same flow out of the packet.

I remember someone on here who had tested a lot (or was it one of the spray operator of the year people - can't remember) of new nozzles. They said they vary a lot more than you might think.

 

[Daniel]

I remember someone on here who had tested a lot (or was it one of the spray operator of the year people - can't remember) of new nozzles. They said they vary a lot more than you might think.

That wouldnt be due to inconsistency in manufacturing of the nozzles though? Personally each time I swap the nozzles and jug test there's nothing in it. If I jug test just before changing then there would be 5-10% variation i'd imagine.

 

[Feldspar]

That wouldnt be due to inconsistency in manufacturing of the nozzles though? Personally each time I swap the nozzles and jug test there's nothing in it. If I jug test just before changing then there would be 5-10% variation i'd imagine.

As I say, I can't remember the exact words, but my memory was that they claimed it was the way they were made.

 

[MDA]

That isn't how gases and liquids flow?

If you have 30 metres of water pipe and drill 10 identical size holes along the length, stop the end up and pump water in at 3 bar then the flow rate will be the same out of each hole after the first couple of seconds.

Like wise a huge extractor fan at the end of shed will draw an equal amount of air through 10 equally sized inlets.

No.
The Darcy- Weisbach equation relates to pressure drop due to friction along a given length of pipe.
The pressure at the nozzle nearest the inlet will be greater than the one furthest away. Larger pipes mean less friction=less pressure drop though but it will happen on any pipe

 

[Daniel]

No.
The Darcy- Weisbach equation relates to pressure drop due to friction along a given length of pipe.
The pressure at the nozzle nearest the inlet will be greater than the one furthest away. Larger pipes mean less friction=less pressure drop though but it will happen on any pipe

How much are we talking? We are talking about 6 metre spray section pipes. Not pipelines that stretch for miles?

 

[Adeptandy]

The SP Chafer I've just got feeds to the middle of the boom section, so should be pretty good

 

[principal skinner]

Because nozzles wear at different rates? They all give the same flow out of the packet.

No they don't, I know that for a fact

 

[principal skinner]

That wouldnt be due to inconsistency in manufacturing of the nozzles though? Personally each time I swap the nozzles and jug test there's nothing in it. If I jug test just before changing then there would be 5-10% variation i'd imagine.

There can be 5-10% difference on SOME new nozzles, jug testing a must, you might be surprised

 

[Daniel]

There can be 5-10% difference on SOME new nozzles, jug testing a must, you might be surprised

But thats down to inconsistency of manufacture? I.e. if you swap the position of the dodgy nozzle on the spray line then it still outputs the wrong amount in its new position.

 

[principal skinner]

But thats down to inconsistency of manufacture? I.e. if you swap the position of the dodgy nozzle on the spray line then it still outputs the wrong amount in its new position.

Yep