HPHT wells bring new challenges to the well design engineer. One of these challenges is connection design and selection. Connections for HPHT wells must be high performance connections that have been fully tested to demonstrate high reliability and fitness for service.

Our objective is to discuss the impact connection design and selection have on these challenges, the reasons for using two seals and the need to test each of the seals independently to ensure an acceptable connection leak probability. Shell uses the industry test standard, ISO 13679:2002 "Petroleum and natural gas industries – Procedures for testing casing and tubing connections"(1) to qualify connections. We will discuss our method for determining reliability of a connection – a probabilistic calculator-its assumptions, and how sensitive the results are to those assumptions.

You can access this article if you purchase or spend a download.