Technology Innovation for Determining Surface Roughness in Pipes

Abstract

Technology Today Series articles are general, descriptive representations that summarize the state of the art in an area of technology by describing recent developments for readers who are not specialists in the topics discussed. Written by individuals recognized as experts in the area, these articles provide key references to more definitive work and present specific details only to illustrate the technology. Purpose: to inform the general readership of recent advances in various areas of petroleum engineering. Abstract Since 1995, several petroleum companies have actively sponsored research on how internal-surface wall-roughness texture affects the flow of fluids in oil-country tubular goods (OCTGs). The research goal focuses on the development and application of new technologies in combating the effects of pipe corrosion, establishing new piping materials and coatings, increasing the ease of fluid flow in pipes, and validating such improvements. A result of the research is a newly developed surface-roughness correlation for modern pipes. Introduction Currently, one area of focus is on achieving infrastructure-cost reductions in the transport of gas and oil through pipelines. Profilometer technology is a good example of one such application that is being adapted from the metal fabrication/manufacturing industry to measure the internal-surface roughness of piping. Internal-surface roughness impedes the dynamic transfer of fluids and is a major factor in the optimization of production tubing and pipeline utilization. Corrosion creates scale and pits along the walls of the piping, which in turn impedes flow and creates a loss of pipewall integrity. Other irregularities result from cutting tools, chatter, abrasive cleaning and preening operations, plating, anodizing, and chemical milling during manufacturing. The roughness of a solid surface is defined as any departure of the actual surface from an ideal datum level known as the nominal level. Surface profiling gauges the ups and downs of a surface, which the human eye cannot discern. The method results in a quick and easy way of calculating the pipe's friction factor. This method is a major step forward in production-tubing and pipeline design. The elimination of expensive and time-consuming flow-loop testing is the most obvious advantage of this technology.