Composite Drill Pipe For Extended Reach Horizontal Drilling
Authors: Lou Alex Y. , Lundberg Chris 
Published: October 2008

Abstract
Development of composite drill pipe is being pursued for the extended reach horizontal drilling by a joint industrial venture team including several oil companies, a composite manufacturer, and an academic institute. This project has been selected by NIST for funding in the Advanced Technology Program due to its broad-base economic potential and a high technical risk. Because of the light weight and high stiffness and strength of advanced composite materials, tension and torque load requirements at the well head can be substantially reduced to extend the reach limit of horizontal drilling. This increase in reach offers an enabling capability that allows oil and gas wells to be developed from fewer and smaller structures in an offshore exploratory and production operation.

Introduction
Over the past three decades fiber reinforced plastic (FRP) has been used extensively in both onshore and offshore applications throughout the petroleum industry worldwide, mainly for hydrocarbon gathering and transmission lines and with limited use for downhole tubing in onshore applications [l-41. American Petroleum Institute (API) has specifications governing the use of low and high pressure fiberglass line pipes and downhole tubings [5]. In offshore applications, there' are uses of FRP products in secondary structures such as railing, grating, walkway, cable tray, water cooling and non-hazardous waste lines. Several studies of advanced composite components have been conducted in offshore applications 16-1 I]. In a recent development in North Sea an FRP firewater system was introduced successfully by Amoco in the Valhall platform [12]. Corrosion and fatigue resistance and light weight are the main factors for the industrial acceptance of FRP products, both onshore and offshore.
In offshore deepwater applications, the weight of a conventional fixed-leg platform increases exponentially with water depth. It is necessary that light weight platform design concepts such as tension leg platforms (TLP) be developed in which substantial weight can be saved by utilizing advanced composites. TLP's are a key factor in the recent success in the deepwater development in the Gulf of Mexico (GOM). Most notable deepwater TLP developments inclqle Auger, Mars and Ram Powell. Although industry acceptance of advanced composites for structure component applications is still in the early stage of development, it is widely recognized that this is an enabling technology in the offshore deepwater arena [13]. Petroleum industry interests in GOM properties increased substantially in recent years as a result of new seismic data. Billion barrels of oil are believed to exist in the GOM. However, the ability to drill deviated, horizontal and extended wells is becoming an important factor in economically developing these offshore fields in both shallow and deep water. Extended reach in horizontal drilling is thus becoming a key in developing remaining offshore reserves by allowing more wells to be produced from fewer platforms.
Advanced composite materials reinforced by carbon, Kevlar, and glass fibers offer great potential for extended reach in horizontal drilling due to their light weight, high stiffness and strength, design flexibility for torsional resistance, and drag reduction. However, in developing composi, te drill pipe products there are several technical barriers and financial risk that need to be overcome.