| 主权项 |
1. Plug for installation in a well, comprising a housing (2) that carries at least two discs (3, 4) of a brittle material that can be fractured by mechanical forces and with a core between the discs (3, 4), characterised in that the core comprises a tightly packed powder material, where the powder particles are not allowed to move in relation to each other as long as the discs (3, 4) are intact. |
