Advanced Collapsible Pipelines For Use In Navy Fuel Systems
Authors: Daniels L.A. 
Published: October 2008

ABSTRACT
The United States Navy?s current ship-to-shore fuel systems use bottom-laid, rigid steel pipe, flexible pipe, or buoyant hose to transfer fuel. The rigid and flexible pipelines place high demands on manpower, shipping weight, and cube, while the buoyant system is environmentally sensitive. New systems of lightweight, high strength, collapsible pipelines? are being investigated as possible replacements. To meet Navy requirements, experimental models of the pipelines have been developed by Angus Fire Armour Corporation, Durodyne, Inc., and Uniroyal Manuli, USA. The research and development conducted on these systems have produced new designs and techniques for conduit construction and operation. High tensile strength couplings, discrete anchoring systems, pliable high density rubber, and highly abrasion resistant covers have been incorporated into the designs. These designs, applications, and materials, as well as the systems themselves, are expected to contribute to the ability of both the military and industry to transfer fuel. High strength (greater than 100,000 pounds working tensile, 1,500 psi burst), lightweight, collapsible fuel lines appear feasible and economical to produce.

BACKGROUND
The research conducted and described here is considered "exploratory development" by the Navy. The need for a lightweight ship-to-shore fuel pipe- line was generated by the requirements of military missions, usually of 6 to 12 months duration. Constraints include small installation craft, inexperienced military personnel, limited bathymetric data, and limited pre-installation preparation. The Navy?s current noncollapsible flexpipe system relies on commercial designs which are for a long service life of 5 to 10 years, installation with commercial offshore construction personnel and vessels, and transport by commercial assets. To effect improvements, such as reduced shipping and handling cube and weight, and to achieve the rapid and rigorous installation demands placed on the military in a time of contingency, trade-offs will be necessary. The installation of offshore fuel systems is part .of the Amphibious Construction Battalion (PHIBCB) tasking. The PHIBCB resources are limited by the very nature of their mission, which is seaborne support of troops on land during a contingency. Their equipment assets are limited to small work barges, some heavy lift equipment on shore, and surveying equipment. Any additional support may come from the assault-follow-on echelon transport vessels, but cannot be assured. Although the resources available and the expedient, 3-day installation scenario differ from that of the commercial sector, it is believed that the high strength, lightweight collapsible hose system developed for this military scenario could be of value to industry.

INTRODUCTION
Both bonded and unbended hose constructions of the high strength, lightweight, collapsible systems are envisioned as having Navy applications. In a bonded construction, all layers, including tube, burst and tension reinforcement, weight additives, and abrasion resistant covering, form a unified hose construction. This integral construction prevents damaging permeation of fluids between layers and is best illustrated by the elastomeric hoses in which the layers are fully vulcanized.