Study of Coring Technology in Sandstone at Well W6, Weizhou Formation, Beibu Gulf

Coring operation has been down recently in the sandstones of main objective Weizhou Formation in Well W6, an evaluation well located in Weixi block, Beibu Gulf. The coring recovery rate is low in the first two coring. In this paper, the difficulties in coring from unconsolidated sandstone in this well have been analyzed, and study has been conducted on coring tool selection, coring parameter optimization, and coring technic measures. These improvements are applied in the subsequent four operations and obvious results have been obtained, and coring recovery is over 98%. The result provides helpful reference for coring in similar formations.