bending fatigue enhancement of synthetic fiber rope papers/tp... · bending fatigue enhancement of...

THE STRONGEST NAME IN ROPE

Bending Fatigue Enhancement of Synthetic Fiber Rope

SAMSONDanielle Stenvers, Justin Gilmore, Rafael Chou

W.L. GORE & Associates, Inc.Robert Sassa, Jeff Leiser, Mike Altman, Gary Harp

Presented by Jon MillerSamson Rope Technologies


PRESENTATION OVERVIEW

Samson Rope Technologies Specific application where bending fatigue is importantPerformance requirements of ropesBending fatigue resistance – testing – improvement

Other considerationsConclusionsFuture work


Founded in 1878, Samson still holds the oldest active RegisteredTrade Mark in the United States

Headquartered in Ferndale, Washington with manufacturing facilities in Ferndale and Lafayette, Louisiana

Largest manufacturer of high performance synthetic rope in NorthAmerica with a full range of products and services

Over 250 employees serving 1,000 customers in more than 25 countries with 250 products

Privately owned by WIND RIVER HOLDINGS

WHO IS SAMSON?


OUR MISSION STATEMENT

Samson is the leading high performance cordage company. Our competitive advantage is to differentiate ourselves by providinghigh performance cordage solutions to critical customer problems.

The competitive advantage is delivered through a combination of application engineering, critical technical capabilities (fibers, coatings, and constructions) and focused technical sales efforts in targeted growth markets.

Products are marketed under the Samson brand as the symbol for high performance, supported by superior customer service and emphasizing the company’s service and quality programs.


The Most Advanced Research and Development in the Industry

PhD

Engineers:

Chemical

Mechanical

OUR CAPABILITIES


The Most Advanced Rope Testing Machine, Capable of Breaking Rope in Excess of 1.1 Million Lbs.

OUR CAPABILITIES …cont’d


Drop Test Tower12 1/2' Drop Length280 kg max drop weight

OUR CAPABILITIES …cont’d


APPLICATION OVERVIEW

Well head on ocean sea floorBecause of extreme depths, wire is no longer an option because of breaking lengthSwells at surface require motion compensation during installation.

SYNTHETIC ROPE OPPORTUNITY


APPLICATION OVERVIEW …cont’d

Installation of Subsea TreesInstallation vessel

Ahv photo here


DESIRED PROPERTIES

StiffnessTension control Abrasion and cuttingTension-tension fatigueBending fatigue resistance


BENDING FATIGUE RESISTANCE ENHANCEMENT

Literature ReviewLife factor discussion– Definition– Dominant factors

Testing equipment and samplesCoating formulation Fiber selection


LIFE FACTOR IN LITERATURE

References1) Handbook of Oceanographic Winch, Wire and Cable Technology

3rd Edition. Funded by NSF and developed for US Navy. Edited by John F. Bash• Aramid rope shows good properties with large sheave diameters • Wire rope cycles from 10^4 to 10^5 with large sheave diameters

2) Improving Bend-over-Sheave Fatigue in Fiber RopesOceans 2003 F. Sloan, R. Nye, and T. Liggett

• BOB shows 7.3 times improvement over 100% HMPE with Polyurethane coating

• Specialty coatings Optimum coating with 100% HMPE showed 45% improvement

Definition:

Life Factor = SF*(D/d)


BENDING FATIGUE TEST MACHINE

Pulley dimension—2 ¾” (root diameter)Stroke length—12”Maximum load—1200 lbsFrequency—0.35 HzTesting is done in dry configuration only.

Load Applied to Sample

12” stroke length


TEST SAMPLES

7/64 inch diameter 8 strand – Blends of HMPE, LCP, GORETM OMNIBENDTM Fiber

1/4 inch diameter 12 strand– Blends of HMPE, LCP, Para-Aramid, GORETM OMNIBENDTM

Fiber


COATING FORMULATION

0%

100%

200%

300%

400%

500%

Type S 0000 0017A 0017G Type F 0017C 0017E

Coating Formulation

Com

pare

d to

10

0% H

MP

E

N/C B C D E F G .

B = standard coating

G = special coating


FIBER SELECTION

High tenacity fibers– HMPE– LCP– Para-Aramid– Blends

Specialty fibers (GORETM Fiber)


0%

100%

200%

300%

100% LCP 100% Para-Aramid

100% HMPEuncoated

HMPE/LCPblend

uncoated

Com

pare

d to

100

%

HM

PE

Coa

ted

FIBER BLEND

100% HMPE best single fiber type

HMPE/LCP blend = 3 x 100% HMPE


FIBER BLEND vs. SPECIAL COATING

0%

100%

200%

300%

400%

500%

100% HMPEuncoated

HMPE/LCP blend uncoated

100% HMPE withspecialty coating

Com

pare

d to

100

%

HM

PE

Coa

ted

HMPE/LCP blend = 3 x 100% HMPEHMPE with Special coating = 4.5 x 100% HMPE


PTFE vs GORE™ OMNIBEND™ Rope break strength comparison

70%

80%

90%

100%

110%

100% HMPE HMPE +OTHER PTFE

HMPE +GORE™

OMNIBEND™

15% GORE™ OMNIBEND™ Fiber

15% PTFE fiber


0%

100%

200%

300%

400%

100% HMPE HMPE+Vectran+GORE fiber

HMPE+ GORE fiber

HMPE+ GORE fiber

GORE™ OMNIBEND™ FIBER BLEND(no coating)

HMPE + High% GORE™

OMNIBEND™Fiber

HMPE + Low% GORE™

OMNIBEND™ Fiber

100% HMPE

GORETM Fiber + HMPE 4 x 100% HMPEBending cycles to

failure vs. 100% HMPE

HMPE/LCP Blend + GORE™

OMNIBEND™ Fiber


FIBER BLEND vs. COATING vs. COMBINATION

100%

936%

0%

200%

400%

600%

800%

1000%

100% HMPEuncoated

HMPE/LCPblend

uncoated

100% HMPEwith special

coating

Com

pare

d to

10

0% H

MP

E C

oate

d

HMPE GORE™

OMNIBEND™Fiber blend and special coating


OTHER CONSIDERATIONS

Tension devicesStiffness requirementsExpected failure mechanism– Bending fatigue dominated?– Tension-tension fatigue dominated?


1,0006,000

11,00016,00021,00026,000

10 30 50 70 90

TCLL

Ben

ding

cyc

les

HMPE HMPE/LCP blend

TENSION-TENSION FATIGUE vs. BENDING CYCLES


GORETM Fiber ePTFE yarn is best

HMPE/LCP blend = 3 x’s 100% HMPE

Coatings = 4.5 x’s 100% HMPE

GORETM Fiber + HMPE = 4x’s 100% HMPE

Special coating + HMPE + GORETM Fiber = 9x’s 100% HMPE

Tensile fatigue, Bend fatigue should be considered

CONCLUSIONS


FUTURE WORK

Construction + Gore Fiber Pattern

TCLL testing of GORETM blended ropes

Larger diameter test—fibers, coatings, and constructions

bending fatigue enhancement of synthetic fiber rope papers/tp... · bending fatigue enhancement of...

Documents