Patent ID: 9376887
Filing Date: 2016-06-28
CPC Classification: E21B

Claim Text:
1. A stuffing box for a fluid production well, the stuffing box defining a circulation passage of a cable working line extending between an upstream end of the stuffing box, configured to be connected to the well, and a downstream end, the stuffing box including at least one packer arranged in the passage to ensure the sealing between an upstream portion and a downstream portion of the passage when the line is inserted in the passage, the stuffing box including a back-pressure resistant valve arranged in the passage to prevent, in case of break of the line, the back-pressure of a fluid from the upstream end towards the downstream end, wherein the or each packer is situated between the upstream end of the stuffing box and the back-pressure resistant valve, no packer being arranged between the back-pressure resistant valve and the downstream end.