Utblåsingssikring for avskjæring av et brønnhullsrør

摘要

An apparatus (301) for severing a wellbore tubular, which apparatus comprises at least one blade (310) for shearing said wellbore tubular, characterised in that said apparatus further comprises a projection (312), in use moveable so as to reduce the structural strength of said wellbore tubular in an area where said wellbore tubular is to be severed.