Conceptual design and comparison of aramid and polyester taut leg spread moorings for deepwater applications

Book · Tue Dec 31 04:00:00 EST 1996

OSTI ID:423170

Wilde, B; Kelly, P; Librino, F; Whitehill, A S

As the offshore industry looks beyond water depths of 3,000 ft for future oil and gas production, the industry standard steel catenary spread mooring (CSM) system used on all floating production systems installed to date becomes increasingly inefficient and costly. An alternative to the CSM is the Taut Leg Spread Mooring (TLSM) system with its characteristic short scope legs and vertically loaded anchors. In water depths greater than 3,000 ft, it has been shown that TLSMs comprised of synthetic mooring lines have performance advantages over systems utilizing steel wire rope and demonstrated potential for significant cost reductions. Early studies investigated the use of aramid fiber rope due to its high strength, lower in-water weight and lower axial stiffness as compared to ropes made from steel. Later studies indicated that the material properties of polyester fiber, primarily its lower Young`s modulus, made polyester mooring lines more suitable for use in TLSMs. As the TLSM knowledge base expanded, aramid rope construction evolved. Earlier efforts to match the characteristics of steel wire rope have given way to new generation soft aramid constructions. This paper compares the mooring performance and total installed cost of a soft aramid TLSM to a typical polyester configuration. Both systems were designed for use in the Gulf of Mexico (GOM) with an FPS based on the Aker P45.

• OSTI ID: 423170
• Report Number(s): CONF-960525--
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
ARAMIDS
BUILDING MATERIALS
CABLES
COMPILED DATA
COST
DEPTH 1-3 KM
DESIGN
MATERIALS TESTING
MOORINGS
NATURAL GAS INDUSTRY
OFFSHORE PLATFORMS
PERFORMANCE
PETROLEUM INDUSTRY
POLYESTERS
SPECIFICATIONS