Application Engineer ACRP May 10th 2012 Mark Pederson Application Engineer ACRP May 10th 2012

Overview Lifting Sling Testing Inspection Retirement Criteria Hardware Introduction to Effect of D:d ratio Single leg tests Grommet tests Basket tests Choker tests Published Spec Sheet Inspection Retirement Criteria Sources for Guidelines Mechanisms that Cause Damage Inspection Items Hardware Class1 Rope Hardware Class2 Rope Hardware Synthetic Rope Specific Hardware

Intro to Effect of D/d on Efficiency The Tighter the Bend the greater the stress Concentration With High Modulus fibers this effect is more dramatic Sling on a Pin:

Intro to Effect of D/d on Efficiency Sling on a Pin:

Intro to Effect of D/d on Efficiency Sling on a Pin: Parallel Core Is effected in a bend

Intro to Effect of D/d on Efficiency Sling on a Pin: Braided Construction is beneficial

Single Leg Testing Single Leg Weakest at base of splice 2:1 D/d recommended Efficiency > 1x Rope Strength

Single Leg Testing Single Leg Single leg slings are used to baseline most rope strengths Theoretical load distributions There is a true loss in bend around pin but each leg around pin only carries ~½ T

Single Leg Testing Single Leg Testing Straight Pull D:d = 8 , 4 , 1 D/d = 1 did not show significant strength loss, however break occurred at the back of the eye (on the pin)

Grommet Testing Grommet strength is actually <2x rope strength Current industry recommendations range from 1.6-1.8x entered

Grommet Testing Grommet configuration highlights bending losses

Grommet Testing D/d  Grommet Strength, Bearing size is critical for assuring proper design and maintaining grommet efficiency

Grommet Testing D/d  Grommet Strength, Bearing size is critical for assuring proper design and maintaining grommet efficiency

Grommet Testing A 1.6-1.8x B 1.7-1.9x C 1.7x D 1.75x Splice Placement on D:d >4 : Splice area centered on the pin allows the legs to more evenly adjust upon loading. Two splices do not produce a more efficient sling. Testing has proven that the splice is more efficient with lower D:d ratios A 1.6-1.8x B 1.7-1.9x C 1.7x D 1.75x

Grommet Testing Grommet Weakest on the back of pin 8:1 D/d recommended Efficiency ≤ 1.6x Rope Strength

Basket Testing Basket

Choker Testing Current recommendations: Test Results*: ASME B30.9 80% (PET roundslings) Flory/Richards* 60% (HMPE slings) Test Results*: 12-strand, HMPE fiber Ranged from 60% - 75% (varied by manufacturer) Choke Angle is critical Choker strength

Choker Testing Single leg and Grommet in Choker 3/8” and ¾”

Lifting Sling Table Layout Similar to ANSI table layout 5:1 Safety Factor built in Common horizontal angles rated for basket lifts Minimum D/d recommended Reductions for lower basket D/d Inspection and retirement Criteria included

Sling Table

Updated Sling Table Choker Slings Adjustable Slings

Large Diameter Sling Testing Tested slings in a large range of sizes Developed a model that is used to design project specific lifts

Overview Lifting Sling Testing Inspection Retirement Criteria Hardware Single leg Grommet Basket Choker Published Spec Sheet Inspection Retirement Criteria Sources for Guidelines Mechanisms that Cause Damage Inspection Items Hardware Class1 Rope Hardware Class2 Rope Hardware Synthetic Rope Specific Hardware

Inspection Retirement Criteria Sources for Guidelines Cordage Institute - International association of rope twine and related manufactures/Suppliers . Educating on the proper use of products through standards CI 2001-04 “Fiber Rope Inspection and Retirement Criteria Rope Type, Damage Description, Reference Txt, Reference Picture, Repair , Downgrade , Retire

Inspection Retirement Criteria Sources for Guidelines Handbook of fibre rope technology [Book] by Henry A. McKenna, J. W. S. Hearle, Nick O'Hear, Textile Institute (Manchester, England) in Books Very similar to the Cordage Institute

Inspection Retirement Criteria Sources for Guidelines Samson Rope

Inspection Retirement Criteria Mechanisms that Cause Damage Excessive Tension / Shock Loading Cyclic Tension Wear External Abrasion Cutting Pulled Strands and Yarns Flex Fatigue or Bending Fatigue Terminations Knots Axial Compression and Kink Bands Hockle, Twist , Kink or Corkscrew Sunlight Degradation Chemical and Heat Degradation Dirt or Grit Particulate

Inspection Retirement Criteria Initial Inspection IF Rope Displays Moderate Wear No history of use Potential injury or damage to equipment = Downgrade or Retire the rope Samson / Cordage Institute / Handbook of fibre rope technology

Inspection Retirement Criteria Cyclic Tension Wear IF: Broken Internal Filaments over Length Matted Filaments at strand rub areas =Downgrade / Retire Samson / Cordage Institute / Handbook of fibre rope technology

Inspection Retirement Criteria External Abrasion IF: Rope Cross Section reduced by 10% in whole rope =Downgrade / Retire Rope Cross Section reduced by 25% =Repair/ Retire Samson / Cordage Institute / Handbook of fibre rope technology

Inspection Retirement Criteria Cutting IF: Rope Cross Section reduced by 10% in whole rope =Downgrade / Retire Rope Cross Section reduced by greater than 10% =Repair/ Retire Samson / Cordage Institute / Handbook of fibre rope technology

Inspection Retirement Criteria Pulled Strand Less than 15% of strands are pulled out a repair can be made. Greater than 20% of strands are pulled out a repair should not be made. Downgrade the rope and retire Samson / Cordage Institute / Handbook of fibre rope technology

Inspection Retirement Criteria Flex Wear on Pulleys/ Rollers IF: Internal Fusion Wear on strand crowns Broken filaments at strand rub points =Downgrade / Retire Samson / Cordage Institute / Handbook of fibre rope technology

Inspection Retirement Criteria Flex Wear on Pulleys/ Rollers

Inspection Retirement Criteria Spliced Eye IF: Cuts Splice Pulling out Incorrect Splice Damaged Thimble =Repair

Inspection Retirement Criteria Creep IF: Rope Exceeds limits set by manufacture History of the rope indicates it is a concern =Retire

Inspection Retirement Criteria Compression

Inspection Retirement Criteria Sunlight Degradation IF: Polypropolene, Brittle and broken outer fibers = Retire Ropes less than 1” diameter, 1yr plus exposure, aramid, nylon, polypro =Retire/ Downgrade

Inspection Retirement Criteria Chemical And Heat Degradation IF: Known exposure = Retire Discoloration, Brittle Fibers, Stiff, =Retire

Inspection Retirement Criteria Dirt or Grit IF: Dirt or Grit is found internally Broken an powdery fiber present = Retire

Overview Lifting Sling Testing Inspection Retirement Criteria Hardware Single leg Grommet Basket Choker Published Spec Sheet Inspection Retirement Criteria Sources for Guidelines Mechanisms that Cause Damage Inspection Items Hardware Class1 Rope Hardware Class2 Rope Hardware Synthetic Rope Specific Hardware

Hardware Hardware Class1 Rope Hardware Lower Strength , Higher Elongation Fibers Plastic Thimbles , Non Reinforced Thimbles , Plastic Spools

Hardware Hardware Class2 Rope Hardware High Strength , Low Elongation Fibers Tubular Thimbles, Reinforced Thimbles, Aluminum Spools

Hardware Hardware Synthetic Rope Specific Hardware / Shackles Wide body shackle Crosby Sling Saver Spool

Hardware Shackles Standard and Wide Body Small D/d for Grommets Quick Easy and readily available

Thank you! Questions