Construction of New Tie-In in the Bolivi´a-Brasil Gas Pipeline Using Hot Tapping Techniques - High Pressure 92 Bar

Abstract

To meet the request of supply of 2,4 MMm3/d of natural gas to Treˆs Lagoas Thermal Electric Plant in Treˆs Lagoas city, it was necessary to install a 12 in. branch in the 32 in. main line of the Bolivia-Brazil Gas Pipeline. The most efficient method for the execution of branch and maintenance repairs in gas pipeline is using the hot-tapping technique, where all work is performed with no need for stoppage and clearance of the line, maintaining the gas flow. This paper covers the entire project, specifications, planning and a detailed job execution to carry out this new city-gate using a fully reinforced T (split sleeve) welded into the pipeline, from the retaining of the company up to the safety measures adopted in the operation. The specifies of the complex and innovative welding procedure, still unprecedented in Brazil, that was performed in the API 5L X70 steel piping at an internal pressure of 9022 kPa, as well as the detailing of tests and inspections performed are also presented herein.