Research and application of steel wire free dropping and fishing downhole chock

In the dropping fishing process of movable downhole chock, complex operating procedure and long operation period universal existed in construction site at present. Steel wire free dropping fishing downhole chock and the relevant equipments were proposed to improve work efficient. This new chock adopted presetting working barrel structure, dropped in the core of chock directly into well using drop in and capture tool in wellhead, then the chock core dropped in depending on self gravity, and finally got into the working barrel and locked it. When fishing it back, first putted the fisher into well from wellhead, second, the energy of ascending natural gas-current in the well derived the fisher to took the chock into ground after the former docking with the chock core, in the end, the fisher captured by drop in capture tool in the wellhead and finished the chock fishing. Field application illustrated that steel wire free dropping fishing downhole chock is stable in work performance, and easy to drop in and fishing, which is worthy to deployment as a new technique of downhole throttling.