Electric gut tracing - an innovative approach to pipeline heating

Abstract

Applying electrical heat tracing to pipelines can dramatically increase the reliability and efficiency of such pipelines. As a matter of fact over the years, electrical heat tracing has played an important role in the enhancement of flow assurance of oil pipelines. In most cases, the application of heat is on the outer surface of the pipeline, taking advantage of the efficient conductivity characteristics of metallic pipe. While the method of adding thermal energy to the product inside through "conduction" is an efficient method, it introduces a few complexities as well. Examples of these complexities include; the necessity for good contact of the heating cable with the pipe surface and the possibility for higher heat losses requiring the use of oversized insulation. More uniform heating can be achieved by installing the heating cable inside the pipe where it is in direct contact with the heated fluid or what is normally known in the industry as "gut" tracing. This paper will evaluate the advantages and disadvantages of using a gut tracing approach to heating pipelines as compared to more conventional outer surface heat tracing methods. We will look at the Finite Element Thermal analysis (FEA) of these conventional systems as well as the gut tracing systems. This paper will address the limitations and reliability of both approaches as well costbenefit analysis and other relevant comparisons. Finally, this paper will identify the ideal applications for a gut tracing approach.