Breakout Session: Design, Fabrication and Testing of Cantilever Beams and Triangle Plates Cantilever beams and triangle plates are valuable specialty rigging tools, but the engineering fundamentals behind their design and use are simpler than they may appear. This presentation will provide examples of commonly used rigging applications and will identify resources for design, fabrication, load testing and lift planning. Speaker: Chad Fox, PE, Project Manager, ruby+associates

1. Triangle Plates &
Cantilever Beams
Applications, Design, Construction &Testing

2. Introduction
• WhyTriangle PL’s & Cantilever Beams?
• Started Eng. Dept w/ Limited Rigging Experience
• Mostly self taught – research & trial/error
• Came to realize how valuable these tools were
• Salesmen were passing on jobs where these are needed
• Possibly under-utilized by smaller to mid size contractors
• Not so complicated – share
?

3. Introduction
• Topic Overview
• Triangle Plates
• Applications
• Sample Projects
• Sample LoadTests
• Resources for Design/Construction/Testing (US Standards)
• Cantilever Beams
• Applications
• Sample Projects
• Sample LoadTests
• Resources for Design/Construction/Testing (US Standards)
• Lift Planning/Procedure
• Feel Free to Ask QuestionsThroughout

4. Triangle Plates – Function
• Orientations
• 2 Engaged
• 3 Engaged – 2 Equally
• 3 Engaged – Unequally

5. Triangle Plates – Function
Engineers:
• Moment Summation to
determine rotation
• ∑MA = 0 = FB x eB – FC x eC
FA
FB
FC
eB eC

6. Triangle Plates - Applications
Load Handoffs: This
application involves
loads between two crane
whether mobile to mobile,
mobile to

7. Triangle Plates - Applications

8. Triangle Plates - Applications

9. Triangle Plates - Applications
Rotation of a Lifted Object:
This application allows a
object to be rotated by
two lines to the triangle
of which lengthens or
rotate the object.

10. Triangle Plates - Projects
• (4) Vertical CTS Heat
Exchangers
• Overhead Crane Vertical
Extents
• Cell Clearances
• Previously Proposed Solutions:
• Roof Opening
• Crane Rail Gantry
• Client: Preliminary Study
• Remove With OH Crane Hook?

11. Triangle Plates – Project – Nuclear

12. Lift Device(Triangle PL) Mechanics
TAILTRUNNION
TRUNNION
OH CRANE

13. Triangle Plates – Load Testing
• LoadTest Needed
• Test Weight Production
• NUREG Requirements
• Additional %

14. Triangle Plates – Load Testing

15. Triangle Plates – Project

16. Triangle Plates – Project

17. Triangle Plates - Applications
3rd Leg Alignment
Adjustment: This
application allows
an adjustable third line to
for rotational variation of
lifted object.

18. Triangle Plates - Projects
Box Section

19. Triangle Plates - Projects
Hoist

20. Triangle Plates - Applications
Cascading System of Slings:
A triangle can be used to
rigging systems with
slings and avoid over-
a hook. This can help to
sling overlap or bunching.

21. Triangle Plates - Projects

22. Triangle Plates - Projects

23. Triangle Plates - Applications
Load Equalization Between Two
Hooks: In instances where multiple
hooks must be utilized due to
limitations of the lifting equipment
the triangle provides an efficient way
distribute the lifted loads relatively
to the two hooks.

24. Triangle Plates - Projects

25. Triangle Plates - Projects

26. Triangle Plates – Load Testing

27. Triangle Plates – Load Sharing

28. Triangle Plates - Applications
Rigging System with Shifting
Center of Gravity: In this
case a triangle allows for
systems such as cantilever
with an adjustable line
center of gravity is shifted
throughout the lifting

29. Triangle Plates - Design
• Resources:
• ASME BTH-1, 2017
• AWS D14.1

30. Triangle Plates – BTH-1 Design
• Design Category (2-2)
• A: FS = 2.0Yield/Buckling & 2.4 Fracture/Conn’x
• *B: FS = 3.0Yield/Buckling & 3.6 Fracture/Conn’x
• C: FS = 6.0Yield/Buckling & 7.2 Fracture/Conn’x
• Service Class (2-3)
• Fatigue/Cycles
• 0 – 4
• Determine Allowable Stress Range

31. Triangle Plates - Design
• Resources:
• ASME BTH-1 Section 3-3.3, Pin PL
• Fitted toTest Results (Duerr, 2006)
• Limit States:
• Tension
• Shear – Single Plane
• Shear – Double Plane
• Out-of-Plane Buckling
• Bearing
• Pins (3.3.6)

32. Triangle Plates - Construction
• Resources:
• ASME B30.20
• Fabrication:
• Boss PL’s
• Capacity and/or Limiting Shackles
• Drill after welding – plies line up
• Local Steel Distribution may be
able to burn shape.
Photo Courtesy of ALL-LIFTS

33. Triangle Plates – Load Testing
• Resources:
• ASME B30.20 (should)
• OSHA, 29 CFR 1926.251 (shall)
• 125% Design Capacity
• Recommend worst case positions
• Certificate
• Be aware overloading Shackles

34. Triangle Plates–Marking
• ASME B30.20 Marking:
• Weight
• Rated Load
• Service Class
• Design Category
• Serial Number
• Manufacturer

35. Triangle Plates – Inspection
• ASME B30.20 Inspection: (20-1.3)
• Designated Person
• Initial Inspection (New or Modified)
• Every Lift Inspection
• Frequent Inspection
• Periodic Inspection (recorded)
• Table 20-1.3.3-1 For Minimum
Frequency per Service (normal,
heavy, severe)

37. Cantilever Beams – Function
• Reach Objects without direct
overhead access
• Equipment installation through
sides of buildings/platforms
• Center of Gravity Over Hook

38. Cantilever Beams – Function
• Shifting COG Depending on
Configuration.
• Beam Only
• Beam + CWT
• Beam + CWT + Object

39. Cantilever Beams – Function
• Heavy Counterweight
• Light object Compared to CWT
• Watch Sloping of Beam
• Simplest Option if Possible

40. Cantilever Beams – Function
• Sliding Counterweight or Hook
• Powered system to move the
counterweight in relation to the
pick point to counterbalance the
lifted load.
• Similar with sliding hook.
• Hydraulically Powered Common.

41. Cantilever Beams – Function
• Adjustable Line to Lift Beam
• Winch Mounted to the Lift Beam
• Self Contained
• Need to Account forWinchWeight
• Mounting Space Needed
• Power

42. Cantilever Beams – Function
• Adjustable Line to Lift Beam
• Using a Secondary Line From
Crane
• Similar toTripping Using Auxiliary
Line
• Run Second LineThrough Block
@Triangle
• Sheaves: Ch. 4 BTH-1

43. Cantilever Beams – Function
• Adjustable Line to Lift Beam
• Hoist Line Above Hook
• Air
• Electric
• Hand (probably lots of work)
• Caution on Angle Loading of
Hoists:
• Contact Manufacturer on allowable
angles.
• Height Limitations Due to
Power/Air/Access Needs

44. Cantilever Beams – Example
• LoadTest – Adjustable line
• Beam
• Counterweight
• Hoist
• Lifted Object
• Grill

45. Cantilever Beams – Example
• Beam Construction
• Steel Shapes Most Efficient:
• Box Sections
• Tubes
• StoutWide Flange
• Slender Shapes More Prone to
Failure by Buckling of the
Compression Flange (Twisting of
the Shape)

46. Cantilever Beams – Example
• Beam Construction
• Shackle/Sling attachment lugs
• Welded Single Lugs (one-time use)
• Welded Continuous (heavy)
• Bolted (removable)

47. Cantilever Beams – Example
• Bolted Lift Lug
• Can Be Re-Used
• Locations Easily Adjusted
• Transferred to Other Beams

48. Cantilever Beams – Example
• Bolted Lift Lug
• If Pretensioned:
• DTIWashers helpful
• Not All Bolts Can Be re-used
(A490, Galvanized)
• Typically Spec A325

49. Cantilever Beams – Example
• End Plates
• Allow For Extensions
• End Fixtures
• Allow Join (2)Together

50. Cantilever Beams – Lift Planning
• Lift Plans Important For Use
• Clearances
• Lengths
• Line Adjustment Needed
• Forces (change)
• Stability Verification

51. Cantilever Beams – Lift Planning
• Beam Only
• COG
• Hoist Length
• Sling Forces

52. Cantilever Beams – Lift Planning
• Beam + CWT

53. Cantilever Beams – Lift Planning
• Beam + CWT + LOAD

54. Cantilever Beams – Lift Planning
• Beam + CWT
• (Load Released)

55. Cantilever Beams – Lift Planning
• Deflection
• Cantilever
• End Supported D = 4”
D = 1”
Cantilever
End Supported

56. Cantilever Beams – Lift Planning
• Bidding Work
• Beam + CWTWill at least Double
total lifted Load
• Crane Upsizing Likely

57. Cantilever Beams- Design
• Resources:
• ASME BTH-1
• Welds: AWS D14.1

58. Cantilever Beams– BTH Design
• Design Category (2-2)
• A: FS = 2.0Yield/Buckling & 2.4
Fracture/Conn’x
• *B: FS = 3.0Yield/Buckling & 3.6
Fracture/Conn’x
• C: FS = 6.0Yield/Buckling & 7.2
Fracture/Conn’x
• Service Class (2-3)
• Fatigue/Cycles
• 0 – 4
• Determine Allowable Stress Range

59. Cantilever Beams- Design
• Resources:
• ASME BTH-1 Section 3-2.3 & 3-2.4
• Yielding
• Buckling
• Engineers: Caution CLTB
• Lug Checks (3-3.3)

60. Cantilever Beams- Construction
• Resources:
• ASME B30.20
• AWS D14.1
• Fabrication:
• Local Steel Distribution may have
drill line.

61. Cantilever– Load Testing
• Resources:
• ASME B30.20 (should)
• OSHA, 29 CFR 1926.251 (shall)
• 125% Design Capacity
• Recommend full Simulation
• Could also use forTraining
• Be aware overloading Shackles
& Hoist
• Bolt-on Lugs – AlsoTested

62. Lift Beams – Marking
• ASME B30.20 Marking:
• Weight
• Rated Load(Difficult…multiple)
• Service Class
• Design Category
• Serial Number
• Manufacturer

63. Cantilever– Inspection
• ASME B30.20 Inspection: (20-1.3)
• Designated Person
• Initial Inspection (New or
Modified)
• Every Lift Inspection
• Frequent Inspection
• Periodic Inspection (recorded)
• Table 20-1.3.3-1 For Minimum
Frequency per Service (normal,
heavy, severe)

64. Summary
• Applications –Triangles
• Handoffs
• Rotations
• Alignment
• Cascading Slings
• Load Sharing
• Shifting Center-of-Gravity

65. Summary
• Applications – Cantilevers
• Inaccessible Access From
above
• Method Options
• Heavy CWT vs Load
• Moving CWT
• Adjustable Line

66. Summary
• Design
• ASME BTH-1
• Find Correct Design Category
• LoadTesting (OSHA
required)
• ASME B30.20 (if standard)
• 125%

67. Summary
• Inspections
• ASME B30.20
• Intervals
• Marking
• ASME B30.20
• Weight
• Rated Load
• Serial #
• Manufacturer
• DC & SC

68. Thank You
David Duerr PE
Bruce Burt PE
Erickson’s Inc
Alberici/Hillsdale
All-Lifts
Triangle Plates & Cantilever Beams:
Applications, Design, Construction &Testing