Proceedings of the Thirty-second (2022) International Ocean and Polar Engineering ConferenceShanghai, China, June 5–10, 2022
Copyright © 2022 by the International Society of Offshore and Polar Engineers (ISOPE)
ISBN 978-1-880653-81-4; ISSN 1098-6189

www.isope.org

Collapse Response of a Single Carcass Offshore Rubber Hose under Bending Moment
Daifeng Wei a, Chen Ana,*, Zhe Zhang a, Jin Zhangb, Aixia Zhangca College of Safety and Ocean Engineering, China University of Petroleum-Beijing, Beijing, Chinab Department of Mechanical Engineering, University of Calgary, Calgary, Alberta, Canadac CNPC Offshore Engineering Co., Ltd. Beijing, ChinaABSTRACT

single carcass rubber hose is affected by the operation and various
environments, and the load on the hose is consisted of the axial load,
torsion load and bending load and so on. One of the main loads on thehose connected to the FPSO or CALM is the bending load in thefloating hose system (Paruolo et al., 2020; Tonatto et al., 2018), and thehose is likely to excessive bending during installation (G P Drumond etal., 2018), which is shown in Fig. 1. Excessive bending load is easy tocause local crushing and buckling of the hose structure, which showedin Fig. 2.

The single carcass offshore rubber hose is mainly composed of layersof steel wire, cords, and rubber materials, and it is used worldwide foroil and gas transport systems. A nonlinear finite element offshore
rubber hose model is created to calculate the collapse response of thehose by the bending moment using Abaqus™ software. The results
demonstrate, the range of diameter and the variation of the pitch of thehelix wire have a great influence on the collapse resistance of the hose.
The stress distribution trend of the cord is different on compressed andstretched zone. The finite element model can predict the collapse
characteristics of the offshore rubber hose and provide guidance for thestructure design of the hose.

KEY WORDS: Stiffened composite rubber hose; bending moment;
finite element modeling; reinforcement layer; collapse resistance.
INTRODUCTION

Fig. 1 Diagram of the ocean application of the hose

The single carcass offshore rubber hose is bonded rubber hose withfiber cords and helix wire steel, which is widely used in offshore oiltransport systems (Amaechi et al., 2021). The characteristics of thesingle carcass offshore rubber hose are larger bore, high pressure, highstrength combined with flexibility, and excellent fatigue resistance. The
single carcass hose group is consisted by the end reinforced hose,
mainline hose, taper hose, tail hose, and barbell rail hose, and it is usedin single point mooring in 1970s (Katona et al., 2009; Ziccardi, 1970)
showed in Fig. 1. A typical single carcass offshore rubber hose isdepicted in Fig. 2. In the illustration, the steel end fitting includes theflange, the nipple, and the annular ribs, which are welded together. Thenipple, the inner rubber layers, the reinforcement layers, and the helix
wire are vulcanized to each other.
The main standard for the single carcass offshore rubber hose is API
17K ( 2018), API 17B (2014), and the OCIMF (2009), which give therules about manufacturing and purchasing. But there are no specificinstructions for the design and evaluate the safety of the hose. TheFig. 2 Typical single carcass offshore rubber hose structure diagram852