摘要 |
In order to ensure that at least some of the tools (12-1) to 12-4) in a string of tools that is permanently installed in an oil well (10) are kept in operation even in the event of a localized fault, the link (18) interconnecting the tools and a surface installation (16) is subdivided into segments by switch members (20). More precisely, a switch member is associated with each tool. In addition, the link (18) forms a loop with both ends thereof being connected to the surface installation (16). |