Spin-off technologies from Development of Continuous Composite Tubing Manufacturing Process
Authors: Lundberg Chris A. , Walsh Thomas J. , Reynolds Harris A. , Peterman Charles P. 
Published: October 2008

ABSTRACT
A NISTIATP sponsored consortium was formed to develop a continuous process to manufacture high quality, long-length composite tubing. The goal of the project was to produce a composite material from a continuous process that equaled the quality of composite material produced using more traditional batch type processes. The project has resulted in continuously produced composite tubing of a quality that meets and, in some cases, exceeds that of batch processed composite materials. The research conducted in this effort to develop the manufacturing process and equipment, resulted in several significant advancements of composite manufacturing technologies. This paper discusses some technological advancements that came from this collaborative effort, including: a method of continuous resin impregnation that yields composite laminae with void contents consistently below 1%, a high speed process for wet pre-preg manufacturing, and a nondestructive inspection method for continuous in-line resin cure measurement. Brief mention is also made of a liner adhesion process. These technologies are key to the reliable production of cost-effective composite products being introduced for use in the oil industry.

INTRODUCTION
In the early 1990's, Hydril embarked on a development effort to assess the feasibility of manufacturing a composite tubular suitable for use in downhole workover operations. The characteristics of corrosion resistance, fatigue resistance and high strength to weight ratios were benefits of composite materials that were of importance in the initial evaluation. The successes of that assessment eventually lead to the formation of a joint industry consortium for the development of an in-line continuous process to manufacture ultra-long length spoolable composite tubing. In that research and development project, a number of innovative processes have been developed. This paper will discuss the a novel device and process for low void resin impregnation, and the attributes of a continuous cure monitoring and measurement process for composite tubular.

ATP/NIST JOINT VENTURE PROJECT FOR SPOOLABLE COMPOSITE TUBING
The US Department of Commerce National Institute of Science and Technology initiated an Advanced Technology Program with a focused program on the Energy Industry in 1994. Key interest in oil and gas industry was developing due to increasing need for cost effective methods and products for production operations. The aim of the DOC ATPINIST was to provide matching funds toward industry programs that were otherwise too risky to pursue. A joint proposal for this initiative was developed for ATP by Shell Development, University of Houston and Hydril Company. The objective of this proposed program was to develop the technology to overcome the barriers to the design, manufacturing, and utilization of a broad range of long continuous lengths of high performance, spoolable composite tubing. Applications for the spoolable composite tubing were identified as:Downhole coiled tubing operations for well maintenance and drillingHigh pressure production and injection FlowlinesHydraulic control umbilicals for subsea wellsFlexible production risers, andDownhole production tubing and casing.
The ranges of typical properties and requirements for these tubulars are shown in Table 1. The Spoolable Composite Tubing Joint Venture (SCT-JV) consortium was formed in conjunction with an ATP grant award for a five year development project.