Optimization and application of high pressure resistant,unblockable,leak proof and plugging system for buried-hill fractured reservoirs in BZ19-6
Fractures in the buried hill reservoirs of BZ19-6 and other blocks have caused frequent leakage during drilling.There is a weathered crust at the top of the buried mountain section,with extremely developed cracks,mostly small to small cracks,which have a significant impact on drilling efficiency.The characteristics and mechanisms of buried hill fractured reservoirs leakage were revealed by analyzing the leakage density,fracture width,and leakage conditions of drilling fluids in blocks such as BZ19-6.The GYD alloy was selected as the bridging material after conducting morphology analysis,acid solubility,temperature resistance,and pressure resistance testing.Brucite fibers were used as the fiber material for mesh capture,while MDF powder and PF-EZCARB powder were used as filling powders.As a result,a high pressure fracturing and plugging and plugging system for buried hills was constructed.The results of the indoor test evaluation indicate that the selected combination of plugging materials effectively seals a wedge-shaped long fracture with an opening of 1.0 mm X 0.5 mm under a pressure of up to 10 MPa.Additionally,it strengthens the network structure of the leak prevention and plugging system and improvs the pressure and plugging performance.The acid dissolution plugging rate is 72.5％,This fluid system achievs"plugging without death,easy to remove plugging"and maximizes the plugging requirements of buried hill reservoirs.The high pressure fracturing and plugging system constructed in this paper has been successfully applied in the deep exploration wells of BZ19-6 block,indicating that it can provide technical support for safe and efficient drilling of the Bohai Sea buried hill reservoirs.
BZ19-6buried hill reservoirfractured stratadrilling fluid leakage
万方数据
维普
