weight optimization of drill steel support in front of the

Weight Optimization of drill steel support in front of the Telescopic Boom of

Face Drilling Machine

Joseph Junior

Background• Face Drilling Machines• Used for mining and

tunneling purposes. • Usually have long telescopic

booms • Carries powerful and heavy

tools in front of long booms

• Should be as compact as possible

• Desired to have higher flexibility, large coverage area on the drilling face, can drill long holes

Background• Drill Steel Support• Located at the front tip of

boom• Closest component to the

rock wall or drilling face• Applies a forces of 25 kN

against the rock wall through a rubber dowel

• Typically a welded plate design or casted steel

Background

Current Design• 15.34 kg• Welded structure• Young's Modulus 210 GPa• Yield Strength 350-360 MPa• Tensile Strength 470-630 MPa• Poisson’s ratio 0.3

Initial Design Target

• Reduce the weight by 15 %• Select an ADI Material and use it for casting the component

Design Constraints

• Keep the mounting interface as the same as the previous design• Able to mount on the existing machine layout

Method

1. 1.New Material

2. Topology Optimization

3. Evaluate Castability

4. Shape Optimization

5. CAD Model

6. Evaluate Castability

New Material

• Austempered Ductile Iron (NE-GJS-900-8 )

• Young's Modulus 169 GPa• Density 7.1 g/cm3

• Poisson's Ratio 0.27• Yield Strength 600 MPa• Tensile Strength 900 MPa

Topology Optimization

Design Spaces Considered for analysis

50/52.3 kg

24 Load Cases Boundary Conditions

Results from the Selected design space

Vol frac 15%Min Thickness 30mmSymmety XY planeSplit Draw XY plane

Vol frac 20%Min Thickness 30mmSymmety XY planeSplit Draw XY plane

Vol frac 20%Min Thickness 40mmSymmety XY planeSplit Draw XY plane

Vol frac 20%Min Thickness 15mmSymmety XY planeSplit Draw XY plane

Desig Space Weight 43.16 kgNet weight 46.90 kg

Shrinkage Porosity from Casting Simulation

Best Result

Wt:10.5 kg

Best Result

Design inspired from the optimization results

Wt: 9.5 kg

Shape Optimization

Parametric Modelling

Shape Optimization Results

Pareto Plot

Volu

me

in m

m3

Fatigue Life

Selected Design

Wt: 7.72 kg

Wt: 9.5 kg

New Design

Factors: Robustness, Deformation limits for the attached components.

Casting Simulation results

Achieved Results

0

38

Perc

enta

ge M

ass r

educ

tion

100

68

15