| 摘要 |
An accident protection device (1) to be mounted in a mainly vertical well casing (2), including one or more protection means, extend radially, diagonally or in another way across well casing. Protection means is joined with one or more adjusting means by means of which the protection means can be fastened at inner wall of well casing and carried by an outer ring, which can be full or divided and extending along inner wall of well casing. Outer ring shows drill template holes with the same mutual location as adjusting means for pre-drilling of holes in inner wall of well casing, into which adjusting means are intended to be brought. |
