T-3000 - Thru-tubing, riggløs plugging av brønner med Bismuth Alloy (M3)

There are more than 2 500 wells on the Norwegian continental shelf that will need to be plugged and abandoned (P&A) in the years to come. Today's solution involves plugging from the rig and is associated with high costs. This project aims to develop and demonstrate a new method for permanent plugging of wells from rigs or vessels using the cable-driven, downhole tool ‘T-3000’. The innovation in this concept is that the tool enables controlled heating and melting of a specially developed Bismuth alloy that will seal the well. The project is an important step on the way towards complete rig-less P&A of offshore wells. The solution provides higher reliability against future leaks from wells, as well as reduced need for handling of special waste. Another feature of the tool/concept is the possibility of cost-effective and environmentally friendly relocation of the well plug in the event of any future need (i.e. CO2 storage or production of 'blue' Hydrogen). The project's value is linked to costs savings and reduction in emissions when P&A activities are transferred from rig to vessel. The first part of the project – is development of system design and operating procedures – this will be carried out during the first quarter of 2024. The project team must identify which components are needed for commissioning and operation of the tool, as well as how these will be coordinated. One would also need to write/develop procedures for preparation of wells, tool itself, as well as operation of tool inside the well. An overview and assessment of well condition and methods for barrier verification must be established. The experience acquired at the early stage of the project is vital for finalizing an overall tool design, which represents the goal for the first phase of the project.

Wellstrøm AS har gjennom IPD-prosjektet for et "big-bore" verktøy gjort noen oppsiktvekkende funn, som gjør at en nå ser muligheten til å utvikle et verktøy som kan sette en bismuth-plugg through tubing, av svært høy kvalitet. Det betyr at mens foregående verktøy kan plugge riggløst i allerede klargjorte brønner, der produksjonsrør er trukket, kan T-3000 sette plugg fra produksjonsrør. En eliminerer da behovet for rigg, når produksjonsrør ikke lenger å trekkes. Legeringen som brukes (M3), tettere sprekker/porer ned til 5 mikron, har en Veritas sertifisert levetid i brønn på 3000 år, og kan når den anvendes i Wellstrøm sitt pluggdesign tåle 9 ganger større trykkforskjell enn ren bismuth. Dette prosjektet omhandler utviklingen og kvalifiseringen av et slikt verktøy fra verksted, via testrigg på land til offshore demontrasjon.