Embed Size (px)
Citation preview
Heat Treatment Methods for Cast and Forged Crane Wheels
AIST Crane Symposium
September 2008
Presented By:Frank PetrekXtek, IncCincinnati, Ohio USAPlzen, Czech Republic
Crane Wheel Failure Modes
Tread Diameter SpallingTread Diameter WearFlange FractureFlange Wear
Objective is to manufacture a wheelthat satisfies all 4 potential failures
Solution for Tread Diameter SpallingSupport Vertical LoadingMaterial Strength
Mechanical PropertiesDepth of Hardness
Diameter of WheelWidth of Rail Head
Objective is to avoid sub-surface shear
failure
Solution for Tread Diameter WearWheel Slides While Rolling Interface Requires Traction
No Lubrication
High Surface HardnessDepth of Hardness
Objective is to Resist Adhesive Wear
Solution for Flange Fracture Stress Concentration in Transition
from Tread to Flange Avoid Stress Riser
Smooth / Gentle Radius No Metallurgical Notch
Material Strength Mechanical Properties
Depth of Hardness with Soft Core
Objective is to avoid formation of a surface
crack that will propagate through fatigue
Solution for Flange Wear Inside of Flange Slides On
Side of Rail Head Ideal Interface has Lubrication
Lubrication Sticks
Metallurgical SolutionHigh Surface HardnessDepth of Hardness Without
Through Hardening the Flange
Objective is to Resist Adhesive Wear
42CrMo4 42CrMo4 42CrMo4 42CrMo4 ASTM A504 42CrMo4 AISI 1055
AISI 4140 AISI 4140 AISI 4140 AISI 4140 AISI 4140 AISI 1070
Normalize and Temper X X
Immersion Quench X
Rim Quench X X
Flame/Induction Harden
X X X
Selective Quench (Contour Harden)
X
Surface Hardness - BHN
220 280 - 320 450 - 500 220 321 - 363 450 - 500 627 - 682
Surface Hardness - HRc
45 - 50 45 - 50 58 - 62
Forged steel
Common Steel Grades
Cast steel
Heat Treatment Methods for Cast and Forged Crane Wheels
Immersion Quenching
General Heat Treatment to All Surfaces
No Customized Properties Introduced into the Rim
Surface Hardness and Hardness Depth Depend on Grade of Steel and Quench Medium
Rim Toughening
Process Derived From RailroadsMaterial ASTM A504 Class C
Identical to Railroad Standard
Entire Wheel Heated Then Water Spray Quenched While Rotating
Relatively Low Surface HardnessGood Toughness in FlangesVery Good Core Properties
Spin HardeningSelective Heating
Flame Heating Induction Heating
Lowered into Quench While Rotation Continues
Wide Variety of SteelsCan Develop Significant
Tread Hardness DepthsFlange Properties Depend
on Heating Controls
Contour (Case) HardeningControlled Atmosphere
Furnace HeatingNo Oxygen
Quenches Only Selected Surfaces
Not a Carburized ProcessOptimizes High Surface
Hardness for Wear With Tread Hardness Depth and Ductile Flange Core Ideal Heavy Loads Ideal for High Cycle Cranes
Cast Wheel Heat TreatmentsNormalize and Temper Immersion QuenchSpin Harden
Flame HeatOr
Induction HeatLower into Quench While
Rotation Continues
Forged Wheel Heat Treatments Normalize and Temper Immersion Quench Rim Toughening Spin Harden
Flame HeatOr
Induction Heat Lower into Quench While Rotating
Contour (Case) Hardening
Comparison of Heat TreatmentsHardness Depths at Middle of Ranges
0
100
200
300
400
500
600
700
0.0 1.6 3.2 4.8 6.4 9.0 9.5 11.1 12.7
Depth Below Surface (mm)
Bri
nel
l Har
dn
ess
(BH
N)
ASTM A504 Class C (321 - 363 BHN) AISI 4140 (450-500 BHN)
CONTOUR HARDENED (56-62 HRc) AISI 4140 Normalized (220 BHN)
ASTM A504 Class C Heat TreatmentHardness Depths versus AIST TR #6
286 267
0
50
100
150200
250
300
350
400
0.0 1.6 3.2 4.8 6.4 9.0 9.5 11.1 12.7 14.3
Depth Below Surface (mm)
Bri
ne
ll H
ard
ne
ss
(B
HN
)
ASTM A504 Max Shear Depth (AIST TR#6 - 914 mm Dia.)
ASTM A504 Max Shear Depth x 1.5 (AIST TR#6 - 914 mm Dia.)
ASTM A504 Class C (321 - 363 BHN)
Comparison of Heat TreatmentsContour Hardened and AISI 4140 Hardness
Depths
338 315
0100200300400500600700
0.0 1.6 3.2 4.8 6.4 9.0 9.5 11.1 12.7 14.3
Depth Below Surface (mm)
Bri
nel
l Har
dn
ess
(BH
N)
Contour Hardened Max Shear Depth (AIST TR#6 - 914 mm Dia.)
Contour Hardened Max Shear Depth x 1.5 (AIST TR#6 - 914 mm Dia.)
AISI 4140 (450-500 BHN)
CONTOUR HARDENED (56-62 HRc)
42CrMo4 42CrMo4 42CrMo4 42CrMo4 ASTM A504 42CrMo4 AISI 1055
AISI 4140 AISI 4140 AISI 4140 AISI 4140 AISI 4140 AISI 1070
Normalize and Temper X X
Immersion Quench X
Rim Quench X X
Flame/Induction Harden
X X X
Selective Quench (Contour Harden)
X
Surface Hardness - BHN
220 280 - 320 450 - 500 220 321 - 363 450 - 500 627 - 682
Surface Hardness - HRc
45 - 50 45 - 50 58 - 62
Forged steel
Common Steel Grades
Cast steel
Heat Treatment Methods for Cast and Forged Crane Wheels
User’s Objective:
Match Material & Heat Treatment with the Crane
Application
0
100
200
300
400
500
600
700
0.0 1.6 3.2 4.8 6.4 9.0 9.5 11.1 12.7
Depth Below Surface (mm)
Bri
ne
ll H
ard
ne
ss
(B
HN
)
Heat Treatment Methods for Cast and Forged Crane Wheels
AIST Crane SymposiumSeptember 2008
Thank Youfor Your Attention!
Presented By:Frank PetrekXtek, IncCincinnati, Ohio USAPlzen, Czech Republic
