Abstract: The present disclosure a pressure-bearing plugging agent, comprises a core, a first coating layer and a second coating layer which are sequentially coated on an outer surface of the core, wherein the core is made of a water-absorbing swellable material, the first coating layer is a paraffin layer, and the second coating layer is obtained by cementing the rigid particles with an adhesive.

Abstract: The present disclosure a pressure-bearing plugging agent, comprises a core, a first coating layer and a second coating layer which are sequentially coated on an outer surface of the core, wherein the core is made of a water-absorbing swellable material, the first coating layer is a paraffin layer, and the second coating layer is obtained by cementing the rigid particles with an adhesive.

Abstract: The present discloses a pressure-bearing plugging composition comprising 1-7 parts by weight bentonite, 0.1-1.5 parts by weight deformation material, 8-18 parts by weight filling material and 4-12 parts by weight modified bridging material, based on 100 parts by weight of water; the modified bridging material comprises a core, and a coating layer coated on an outer surface of the core, and a paraffin layer disposed between the core and the coating layer; the core is made of a water-absorbing material, and the coating layer is formed by bonding rigid particles and an adhesive.

Abstract: A fiber silica composite microsphere for a shale stratum comprises a hollow silica sphere and fibers, and the fibers are partially coated on an outer surface of the hollow silica sphere and partially embedded into an interior of the hollow silica sphere. The hollow silica sphere has an outer diameter of 1-5 ?m and an inner diameter of 0.8-4.7 ?m; the fibers have a length of 5-10 ?m and a width of 1-3 ?m.

Abstract: An expandable plugging agent is described. The expandable plugging agent is obtained through a polymerization reaction of acrylamide, a strength improving material, an acrylate, and gelatinized colloid, the acrylate is obtained through a neutralization reaction of an acidity neutralizer and acrylic acid, and the gelatinized colloid is obtained through a gelatinization reaction of starch in deionized water.

Abstract: The present invention discloses a micro-nano composite plugging agent for drilling fluid, a preparation method of the micro-nano composite plugging agent for drilling fluid, a drilling fluid, and an application thereof. The composite plugging agent contains nanometer calcium carbonate, nanometer zinc oxide whiskers, nanometer emulsified paraffin, a flocculating agent, and a lubricant, wherein in the composite plugging agent, the nanometer calcium carbonate is in 10-36 parts by weight, the nanometer zinc oxide whiskers are in 20-40 parts by weight, the nanometer emulsified paraffin is in 30-70 parts by weight, the flocculating agent is in 1-10 parts by weight, and the lubricant is 5-20 parts by weight.

Abstract: A gel plugging slurry for well drilling, comprising water, special gel, bridging material, linking material, and packing material, wherein based on 100 parts by weight of the water, the amount of the special gel is 1-15 parts by weight, the amount of the bridging material is 8-20 parts by weight, the amount of the linking material is 20-40 parts by weight, and the amount of the packing material is 25-45 parts by weight. The gel slug plugging method including simple operation and low requirement for ambient environment; besides, the bridging material, linking material and packing material in the gel plugging slurry form stable structures in the gel, and thereby the gel plugging effect can be improved effectively.