Design Methodology: Code-Driven Design Of Pipelines In Deep Water

Abstract

ABSTRACT The present day approach to writing and presenting Engineering Design Codes and Standards could be measurably improved by adopting a methodological approach to their composition. Current design Methodologies are examined to establish their adaptability to such a role. It is concluded that a multidimensional relationship could be successfully developed in such a way as to integrate the preparation of codes with their intended use as design models. Examples of existing Codes, with a particular emphasis on pipelines for use in deep water, are used to demonstrate one such development. It is proposed that Codes might be produced as stand-alone tools of design methodology and that a new approach to their composition could lead to a more effective, productive and efficient utilisation of their content. INTRODUCTION The design of underwater pipelines suitable for the transportation of hydrocarbon products has been going on since before the first pipeline was laid, whenever that may have been. Certainly a few decades have passed since then. Like any other specialist discipline, subsea pipelines have their own peculiarities and they must be properly, rigorously designed to minimise the possibility of catastrophic rupture, with subsequent loss of production, loss of revenue and, above all, the environmental consequences of such an event. Pipelines are being laid in deeper and deeper water as the search for recoverable resources is extended. It is certain that these peculiarities will not became more easily addressed; the reverse is almost certain to be the case. The pipeline engineer has a number of tools at his elbow to aid him in his design work and to help make sure that the finished product is "fit for purpose". He has a number of codes at his disposal to which he can make reference for guidance on what is considered mandatory and to assist him in evaluating his analyses such that those bodies responsible for the acceptance of the design, including his client, will have confidence in the package which he produces for approval and acceptance. Such Codes include:IP6API RP1111DnV rules8S8010 At his elbow he might also have an in-house set of design guidelines or even a sophisticated suite of software programmes. He might have a mathematical package to do the complex calculations, a graphics package to represent results. It would be even nicer if he had a good, solid design methodology at his fingertips; it would be more economic and less prone to error. Recognised design methodologies too have been around for a few decades. The latest trend of thought is to marry a design methodology with a software solution, something that has not really been available until the recent advent of affordable, real computing power, currently in the shape of 32 bit, 66 MHz desk top computers.