ADJUSTING THE FORAGE HARVESTER FOR CORN SILAGE PARTICLE SIZE

1
ADJUSTING THE FORAGE HARVESTER FOR CORN SILAGE
PARTICLE SIZE
Ronald T. Schuler, Professor Extension
Agricultural Engineer Biological Systems
Engineering Department University of
Wisconsin-Madison
Team Forage
2
Corn Silage Particle Size-Factors

• Machine Adjustment
• Feed roll and cutterhead
• Crop processor
• Crop maturity
• Storage
• Animal

3
Forage Harvester

• Functions
• Gather the crop
• Size the crop, primarily length of forage
  particles
• Deliver crop to transport unit

4
Typical Configuration

• Crop Unit
• Hay head or row crop
• Feed rolls
• Compressing material for cutting
• Determining TLC
• Cutterhead
• Chopping material
• Crop Processor
• Crop damage
• Blower

5
Typical Configuration of Pull Type Harvester
Processor
Feed rolls
Cutterhead

Auger
6
Feedrolls

• Typically two sets
• Larger, front set for feeding
• Smaller, rear set to meter material into the
  cutterhead
• Bottom rolls are fixed
• Can contain metal detectors
• Top rolls float
• Spring pressure to grip material

7
Feed rolls

• controls the rate of feeding into cutterhead
• compresses mat of material so it is easier to cut

8
Theoretical Length of Cut

• Definition - feed roll travel per knife
• Recommendations
• Dependent on
• Animals
• Feed handling equipment
• Crops
• Corn silage - 3/8 in.(no crop processor)
• Corn silage - 3/4 in.(crop processor)

9
Theoretical Length of Cut

• Adjusting theoretical length of cut
• Feed roll speed
• Number of knives
• Cutterhead speed
• Not practical

10
Actual Length of Cut

• Longer than the TLC
• Windrowed crops longer than row crops
• Alfalfa feeds in a tangled mat of material
• Corn stalks feed mostly straight

11
Crop Processor

• Blower
• Crop Processor
• Cutterhead
• Feed rolls

12
Crop Processing

• Used only for whole plant corn silage
• Kernels are difficult to digest
• Contain starch and energy
• Damaging the kernel shell allows the rumen
  bacteria to digest the starch
• Breakup cob pieces (avoid hockey pucks)

13
Crop Processing

• In the past, very short lengths of cut were used
  to damage more kernels
• Recutter screens also used
• Increased power requirements drastically
• Shortened fiber length too much

14
Crop Processor Characteristics

• 1 15 mm (1/16 to 5/8)-clearance range
• 5 25 speed difference
• Speed 2500 4000 RPM
• 3 6 grooves per inch

15
Crop Processing

• A properly adjusted kernel processor
• Damages more than 90 of the kernels
• Pulverize cob pieces
• Minimizes waste in the feed bunk
• Allows for longer length of cut
• Longer fiber
• Less power consumption

16
Crop Processor Pulleys
17
Crop Processor
Clearance Adjustment
18
Crop Processing System
Cutterhead
Processing Rolls
19
Differential speed between rolls
20
(No Transcript)
21
(No Transcript)
22
(No Transcript)
23
Crop Processor - Tips for Success

• Increase the theoretical length of cut (TLC) to
  ¾
• Processor will reduce overall particle size
  further
• Set roll gap between 0.08 and 0.12 (2-3 mm)
• Will result in 100 cob breakage and 90-100
  kernel damage

24
Dont crop processors take A LOT of extra
horsepower??

• Not if set up properly!
• Power consumption for
• 3/4 TLC and a processor set to 0.20 (2.70
  Hp-hr/ton)
• is only slightly higher than
• 3/8 TLC with no processor (2.69 Hp-hr/ton)

25
(No Transcript)
26
Roll Wear

• PTFH - Rolls Wear At Center
• SPFH - Rolls Wear At Edges
• Helical Knives - Uneven Wear
• As Teeth Wear
• Capacity Is Reduced
• Plugging More Likely
• Processing More Difficult

27
Dealing with Worn Rolls

• Replacement 1,500 per Roll
• Re-Grooving 1/3 to 1/2 Cost of New
• Re-Grooving Considerations
• Wont Last As Long As Original
• Can Only Be Done Once
• Tolerances Not As Good

28
WHAT TO LOOK FORIN A CROP PROCESSOR

• Roll Diameter
• Tooth Pitch
• Ease of Checking and Adjusting Roll
  Clearance
• Ease of Unplugging
• Ease of Switching Between Corn silage and
  Haylage

29
Machine Power Consumption

• Gathering and feeding
• 20 of total
• Cutterhead and processor
• 40 50 of total
• Blowing into wagon / truck
• 30 40 of total

30
Reducing Power Loss

• Maintain sharp knives
• Keep close knife to shearbar clearance
• Properly adjust processor
• Keep blower band clearance small

31
Concluding Remarks

• No Processor-TLC0.375 in.
• Processor-TLC 0.75 in and
• roll clearance 0.8 to 0.12 in.

32
Questions
33
QUESTIONS