INCREASING WATER DEPTH WINDOW FOR MOORED SUBSEA STRUCTURES AND OPERATIONS WITH LOW WEIGHT HYBRID ROPES

摘要

This paper introduces new hybrid wire rope concepts by combining steel wire and UHMWPE fibers. These novel High Modulus Hybrid Ropes (HMHR) result in enhanced strength and significant reduction of linear weight compared to steel wire rope (SWR) of equivalent constructions. Compared to fiber ropes (FR) this new family of ropes shows increased protection against crushing, fretting and wear. In-house and independent laboratory tests showed increased breaking load / weight advantages compared to SWR, while also revealing improved bending fatigue resistance. Additionally, test results show similar axial stiffness and torque performance to SWR, which can be modeled by using analytical algorithms. Furthermore creep rate of these ropes is comparable to that of SWR. Finally, the authors discuss the expected performance of these ropes working in deep waters and under high load conditions in offshore and subsea systems. Additional work required to validate and introduce these ropes in the industry is addressed as well.