jeff ensell -- milling & paving for smoothness
DESCRIPTION
Presentation delivered at the CalAPA Spring Asphalt Pavement Conference April 9-10, 2014 in Ontario. Topic: Milling and paving asphalt for smoothness from the perspective of an equipment manufacturer, including best-practices, technology and more.TRANSCRIPT
Milling For Smoothness
Continuous MillingThere are a lot of forces generated during milling.When you stop so do the forces.Plus all of the teeth now cut in one spot, no longer spread out.
Importance of the Water System
Too much water presents problems:
Water costs money.
Excessive water makes the water truck driver have to go and fill up more often and it maybeYou..
Inlaying use as little water as you can.
Water usages are: dust control, toothcooling, and tooth rotation. Use only enough to accomplish these 3 things.
We have to stop to get the water.
RX-900
AM
AUTO
2D Control Systems
AUTO
AM
AUTO
V
L R
MA
RX-900
AUTO
AM
AUTO
V
L R
MA
Averaging Systems
AM
AUTO
3D Control Systems
Mill to Grade based on Position
Proper Maintenance
Proper Maintenance
Proper Holder Wear
anti-seize
Tool Wear Characteristics
At Stage 3Tool has lost 0.365 “ [9.3 mm] of
gage height
0.43 in20.15 in2 287% Increase in Surface Area
Production Tradeoff
0 2 4 6 8 10 12 140
20
40
60
80
100
120
140
160
180
RX-900 New Teeth
Milling Depth (inch)
Adva
nce
Rate
(fpm
)
0 2 4 6 8 10 12 140
20
40
60
80
100
120
140
160
180
RX-900 New Teeth
RX-900 Stage 4 Teeth Wear
Milling Depth (cm or inch)
Adva
nce
Rate
(mpm
or f
pm)
Production Tradeoff
Look at the Holders
Caliper set at EXACTLY 2”
The tooth tip should be centered on the blue line.
The red line shows the misalignment of the tooling due to the face wear on the tooth holder.
Novatec Diamond, Kenamental
•
Both fit into a Kenametal quick change holder
Both are the same height
Tooth Pattern
Keep it Clean
Your Cut surface is only as good the surface you Walked on.
If you have this to work with you willnever achieve grade.
Why?
Clean up your messOur shovel is on the water truck.
The automatics will take that out…
The Math of Milling
Drum RPM
ForwardSpeed
Line Spacing
0Lacing Pattern
Diameter
The 4 Main Factors that Affect Surface Texture1. Line Spacing2. Forward Speed3. Drum RPM4. Lacing Pattern
Line Spacing and Texture
5/8” (16mm) Triple Wrap Lacing Pattern
5/8” 5/8”
≈⅛”
5/8” (16mm) Triple Wrap Lacing Pattern
5/8” (16 mm) Triple Wrap at 30 fpm
2/10” (5mm) Triple Wrap Lacing Pattern
0.2”
≈1/16”
2/10” (5mm) Triple Wrap Lacing Pattern
2/10” (5mm) Triple Wrap Lacing Pattern
Amount of Tools
12’6” (3.5 m) Full Lane DrumLine Spacing # of Teeth Cost of Teeth
5/8” (16 mm) 268 $13403/8” (9 mm) 406 $20300.2” (5 mm) 770 $3850
Nearly 3 times more teethNearly 5 times the cost
No more quick change holders
Production Tradeoff
0 2 4 6 8 10 12 140
20
40
60
80
100
120
RX-900 12'6"
Milling Depth (inch)
Adva
nce
Rate
(fpm
)
Production Tradeoff
0 2 4 6 8 10 12 140
20
40
60
80
100
120
RX-900 12'6"
RX-900 12'6" Micro
Milling Depth (inch)
Adva
nce
Rate
(fpm
)
The Math of Milling
Drum RPM
ForwardSpeed
Line Spacing
0Lacing Pattern
Diameter
The 4 Main Factors that Affect Surface Texture1. Line Spacing2. Forward Speed3. Drum RPM4. Lacing Pattern
Forward Speed
Advance Rate = 30 fpmDrum Diameter = 46”Drum Speed = 100 rpm
Advance Rate = 30 fpm
MachineAdvance
3.6”
0.071”
30 fpm
Advance Rate = 60 fpm
MachineAdvance
7.2”
0.28”
Advance Rate = 60 fpmDrum Diameter = 46”Drum Speed = 100 rpm
60 fpm
Advance Rate = 120 fpm
MachineAdvance
14.4”
1.16”
Advance Rate = 120 fpmDrum Diameter = 46”Drum Speed = 100 rpm
120 fpm
30 fpm vs. 120 fpm
2.3 miles in a day vs. 9.1 miles in a day
The Math of Milling
Drum RPM
ForwardSpeed
Line Spacing
0Lacing Pattern
Diameter
The 4 Main Factors that Affect Surface Texture1. Line Spacing2. Forward Speed3. Drum RPM4. Lacing Pattern
Drum Speed
RX-900 Drum SpeedsEngine Speed Top Sheave Bottom Sheave Gear Ratios Diameter (in) Diameter (in) 20:1 24:1
2100rpm 16 14 120rpm 100rpm2100rpm 16 15 112rpm 93rpm2100rpm 14 15 98rpm 82rpm2100rpm 14 16 92rpm 77rpm
The Math of Milling
Drum RPM
ForwardSpeed
Line Spacing
0Lacing Pattern
Diameter
The 4 Main Factors that Affect Surface Texture1. Line Spacing2. Forward Speed3. Drum RPM4. Lacing Pattern
Drum LacingsScroll Start Comparisons
Triple Wrap Double Hit Quad Wrap
Double Hit Drums
Above
Double hit Quad wrap drum
Standard triple wrap drumBelow
Pattern Comparison
7/8” DHQW at 100 FPM5/8” Triple Wrap at 100 FPM
Production Tradeoff
0 2 4 6 8 10 12 140
20
40
60
80
100
120
RX-900 12'6"
RX-900 12'6" Micro
Milling Depth (inch)
Adva
nce
Rate
(fpm
)
Production Tradeoff
0 2 4 6 8 10 12 140
20
40
60
80
100
120
RX-900 12'6"
RX-900 12'6" Standard DHQW
RX-900 12'6" Fine DHQW
RX-900 12'6" Micro
Milling Depth (inch)
Adva
nce
Rate
(fpm
)
Thank you & Slow Down