Indian Journal of Science and Technology

Abstract

Background/Objectives: Historically the most applied pipe material for gas transportation is steel, but polyethylene and fiberglass are also used. The purpose of this article is to present the results of a comprehensive study of the possibility to use composite pipes. Methods: A multivariate experiment to refine the method for calculation of reinforced polyethylene pipes consisting of three layers was carried out using pipe samples specially prepared in the laboratory; the economic effect of composite pipes introduction during the construction of gas pipelines instead of traditional steel was analyzed on the basis of the calculation of net present value and profitability index using the industrial data for offshoot pipeline construction. Findings/Improvements: The literature and statistical data analysis shows an increase in the length of composite pipelines over the last 10 years and their defect-free; a classification of multilayer pipes offered by various manufacturers was first developed and proposed and a diagram of product characteristics is presented; advantages and disadvantages of using these pipes for hydrocarbon transport streams are shown. According to the laboratory experiment the regression coefficients for mathematical model of a composite pipe were obtained for the first time and the assumption of the joint participation of polyethylene and a reinforcing frame to ensure overall pipe strength was confirmed, as well as the method of calculating the critical pressure for a classical composite pipe was proposed and conclusions about the nature of the pipe wall destruction were represented. The profitability index of the project, built of composite materials, compared to the project, built of traditional materials, shows a higher efficiency of the former by 34%, which enables to reduce the costs of social projects without reducing investment totally. Application: The investigation results can be used in creating the methodological and regulatory base for the implementation of multi-layer composite pipes of different designs in the oil and gas industry.

Keywords:  Fiberglass, Gas Transportation, Natural Gas, Polyethylene Pipes, Reinforced Pipes