Dribble bars..

[grainboy]

Not trying to be difficult, but couldn’t you drill the field, left to right.

 

[Brisel]

Just a question re differing pressure at end of boom. If you have recirculating lines then surely this cannot be so ?

Extra pipework to minimise frictional losses and restrictions will not overcome the additional pressure due to gravity when the boom height is different from one end to the other. In this case, a small change in pressure makes a big change in dose rate due to the Autostreamer dribble bar design. A normal pressure restricted bar with different slide hole settings wouldn't have this issue with good plumbing.

 

[fred.950]

Not trying to be difficult, but couldn’t you drill the field, left to right.

If you are referring to me then yes I could drill it the other way but it’s over 2 km long the way we do it and only 500m the other way. I would like to get it sorted properly if possible. @BFSfertilisers has kindly made contact but I’ve not spoken with them yet.

 

[e3120]

In theory pwm tech could be helpful, as it's a similar manifestation to the under/over dosing on sweeping bends.

 

[Brisel]

In theory pwm tech could be helpful, as it's a similar manifestation to the under/over dosing on sweeping bends.

Pulse Width Modulation still requires a constant pressure to get the desired dose rates right. Each nozzle is not monitored or metered, beyond what the computer pulses are doing to the valves. PWM would work well with dribble bars, but Autostreamers would need some thought.

 

[e3120]

Pulse Width Modulation still requires a constant pressure to get the desired dose rates right. Each nozzle is not monitored or metered, beyond what the computer pulses are doing to the valves. PWM would work well with dribble bars, but Autostreamers would need some thought.

Just thought that if the controller was aware of the pressure response curve and the angle of the boom if could theoretically adjust the pulse width to compensate.

Have you ever observed any signs of across-boom variation on chem/fert, as your boom width/rolling hills would be most susceptible? Effect should be more apparent at lower pressures.

 

[fudge]

Just thought that if the controller was aware of the pressure response curve and the angle of the boom if could theoretically adjust the pulse width to compensate.

Have you ever observed any signs of across-boom variation on chem/fert, as your boom width/rolling hills would be most susceptible? Effect should be more apparent at lower pressures.

Plus or minus 10% is surely accurate enough for fertilizer. So why bother with ridiculously complex maths necessary if chafer bars work fine without PWM?

 

[e3120]

Plus or minus 10% is surely accurate enough for fertilizer. So why bother with ridiculously complex maths necessary if chafer bars work fine without PWM?

Oh, I agree. Just a winter's evening thought exercise. Slightly ironic, though, when hearing how much spinner variation there is unseen when compared to liquid.

 

[Jim75]

All the chats about streamer bars, what about umbrella nozzles? Just weighing up where to start

 

[Brisel]

Just thought that if the controller was aware of the pressure response curve and the angle of the boom if could theoretically adjust the pulse width to compensate.

Have you ever observed any signs of across-boom variation on chem/fert, as your boom width/rolling hills would be most susceptible? Effect should be more apparent at lower pressures.

I'm not an engineer but I guess it's just a matter of software. I'd still prefer not to run Autostreamers on steep slopes. I've never had any issues with Streambars or umbrella nozzles on sloping land, though you need over 20% coefficient of variance before you see it with disc spreaders. A fraction of a bar difference might not show up on those.

 

[Oscar]

I contract apply over a 1000 tonnes of liquid fert on plenty of slopes and hills but have never seen a difference across the boom as in the picture. I have always used Accurate bars from and on Bateman sprayer . Did seriously look at the Autostreamers but decided to keep it simple and proven. It only takes maybe 5 minutes max to get out rotate the restictor on each bar if your changing rates majorly on a 36m boom.