Bending Fatigue Enhancement of Synthetic Fiber Rope

Transcrição

Bending Fatigue Enhancement of
Synthetic Fiber Rope
SAMSON
Danielle Stenvers, Justin Gilmore, Rafael Chou
W.L. GORE & Associates, Inc.
Robert Sassa, Jeff Leiser, Mike Altman, Gary Harp
Presented by Jon Miller
Samson Rope Technologies
THE STRONGEST NAME IN ROPE
PRESENTATION OVERVIEW

Samson Rope Technologies
Specific application where bending fatigue is important
Performance requirements of ropes
Bending fatigue resistance
– testing
– improvement
Other considerations
Conclusions
Future work
WHO IS SAMSON?
Founded in 1878, Samson still holds the oldest active Registered
Trade 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 North
America 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
OUR MISSION STATEMENT
Samson is the leading high performance cordage company. Our
competitive advantage is to differentiate ourselves by providing
high 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.
OUR CAPABILITIES

The Most Advanced Research and Development
in the Industry
PhD
Engineers:
Chemical
Mechanical
OUR CAPABILITIES …cont’d
The Most Advanced Rope Testing
Machine, Capable of Breaking Rope in
Excess of 1.1 Million Lbs.
OUR CAPABILITIES …cont’d
Drop Test Tower
12 1/2' Drop Length
280 kg max drop weight
APPLICATION OVERVIEW
Well head on ocean sea floor
Because of extreme depths,
wire is no longer an option
because of breaking length
Swells at surface require
motion compensation during
installation.
SYNTHETIC ROPE
OPPORTUNITY
APPLICATION OVERVIEW …cont’d
Installation of Subsea Trees
Installation vessel
Ahv photo here
DESIRED PROPERTIES

Stiffness
Tension control
Abrasion and cutting
Tension-tension fatigue
Bending fatigue resistance
BENDING FATIGUE RESISTANCE
ENHANCEMENT
Literature Review
Life factor discussion
– Definition
– Dominant factors
Testing equipment and samples
Coating formulation
Fiber selection
LIFE FACTOR IN LITERATURE
References
1) 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 Ropes
Oceans 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
Load Applied
to Sample
12” stroke length
Pulley dimension—2 ¾” (root diameter)
Stroke length—12”
Maximum load—1200 lbs
Frequency—0.35 Hz
Testing is done in dry configuration only.
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
500%
Compared to
100% HMPE
B = standard coating
400%
G = special coating
300%
200%
100%
0%
N/C
Type S
B
0000
C
0017A
D
0017G
E
Type F
Coating Formulation
F
0017C
G
0017E
.
FIBER SELECTION
High tenacity fibers
–
–
–
–
HMPE
LCP
Para-Aramid
Blends
Specialty fibers (GORETM Fiber)
Compared to 100%
HMPE Coated
FIBER BLEND
100% HMPE best single fiber type
300%
HMPE/LCP blend = 3 x 100% HMPE
200%
100%
0%
100% LCP
100% Para- 100% HMPE
Aramid
uncoated
HMPE/LCP
blend
uncoated
Compared to 100%
HMPE Coated
FIBER BLEND vs.
SPECIAL COATING
500%
HMPE/LCP blend = 3 x 100% HMPE
HMPE with Special coating = 4.5 x 100% HMPE
400%
300%
200%
100%
0%
100% HMPE
uncoated
HMPE/LCP blend 100% HMPE with
uncoated
specialty coating
PTFE vs GORE™ OMNIBEND™
Rope break strength comparison
15% GORE™
OMNIBEND™ Fiber
110%
100%
90%
15% PTFE fiber
80%
70%
100% HMPE
HMPE +
OTHER PTFE
HMPE +
GORE™
OMNIBEND™
GORE™ OMNIBEND™ FIBER BLEND
(no coating)
GORETM Fiber + HMPE
4 x 100% HMPE
Bending cycles to
failure vs. 100% HMPE
400%
300%
200%
100%
0%
+ Low%
HMPE
+ High%
HMPE/LCP
100%
HMPE+Vectran+
HMPE+
HMPE+
100%HMPE HMPE
GORE™
GORE™fiber Blend
+ GORE™
GORE fiber
GORE
GORE
fiber
HMPE
OMNIBEND™
OMNIBEND™ OMNIBEND™ Fiber
Fiber
Fiber
Compared to
100% HMPE Coated
FIBER BLEND vs. COATING
vs. COMBINATION
936%
1000%
800%
600%
400%
200%
100%
0%
100% HMPE
uncoated
HMPE/LCP
blend
uncoated
100% HMPE
with special
coating
HMPE
GORE™
OMNIBEND™
Fiber blend and
special coating
OTHER CONSIDERATIONS
Tension devices
Stiffness requirements
Expected failure mechanism
– Bending fatigue dominated?
– Tension-tension fatigue dominated?
Bending cycles
TENSION-TENSION FATIGUE vs.
BENDING CYCLES
26,000
21,000
16,000
11,000
6,000
1,000
HMPE
10
HMPE/LCP blend
30
50
TCLL
70
90
CONCLUSIONS
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
FUTURE WORK
Construction + Gore Fiber Pattern
TCLL testing of GORETM blended ropes
Larger diameter test—fibers, coatings, and
constructions