Abstract: A sand control screen for heavy oil thermal recovery, including: a core base pipe having a plurality of base-pipe holes distributed on a pipe body thereof; a filtering sleeve sleeved on the core base pipe and arranged with respect to the base pipe holes; and a non-welded support disk mounted on the core base pipe and fastening the filter sleeve to the core base pipe by means of a wedge insertion locking and sealing structure. The invention solves the problems in the prior art in which sand control screen has a poor reliability in a high-temperature condition of a thermal production well, resulting in potential safety risks of down hole sand control operation of the screens. In addition, the sand control screen of the present invention has a long service life, thus improving cost effectiveness of oil wells.

Abstract: A liner hanger top packer comprising a body and, an adjusting sleeve, a retaining apparatus, a base-sealing apparatus, a base-hanging apparatus and a locking mechanism sleeved sequentially from top to bottom on the body. The locking mechanism is arranged between the base-sealing apparatus and the base-hanging apparatus. The locking mechanism comprises a locking ball sleeve, a ball socket, and a steel ball. As the lower part of the liner hanger top packer is met with friction, the arrangement of the steel ball restricts relative axial movements between an upper gauge ring of the base-sealing apparatus, the locking ball sleeve, and an upper conical body of the base-hanging apparatus, the friction transmitted to the upper conical body is not transmitted to a lower gauge ring of the base-sealing apparatus, is transmitted to the upper gauge ring via the steel ball, and is transmitted to the adjusting ring via the retaining apparatus.

Abstract: A liner hanger top packer comprising a body and, an adjusting sleeve, a retaining apparatus, a base-sealing apparatus, a base-hanging apparatus and a locking mechanism sleeved sequentially from top to bottom on the body. The locking mechanism is arranged between the base-sealing apparatus and the base-hanging apparatus. The locking mechanism comprises a locking ball sleeve, a ball socket, and a steel ball. As the lower part of the liner hanger top packer is met with friction, the arrangement of the steel ball restricts relative axial movements between an upper gauge ring of the base-sealing apparatus, the locking ball sleeve, and an upper conical body of the base-hanging apparatus, the friction transmitted to the upper conical body is not transmitted to a lower gauge ring of the base-sealing apparatus, is transmitted to the upper gauge ring via the steel ball, and is transmitted to the adjusting ring via the retaining apparatus.

Abstract: The present invention provides a starch-(meth)acrylate graft copolymer and the preparation process thereof. The starch-(meth)acrylate graft copolymer is prepared by copolymerizing (meth)acrylate monomer and starch in a weight ratio of (0.4˜8):1, the graft copolymer having a skeleton of large starch molecule is grafted with one or more (meth)acrylate monomer with a grafting ratio of no less than 70%. The present invention further provides an oil swellable material, which comprises the starch-(meth)acrylate graft copolymer above as the swelling agent; and also an oil- and water-swellable material, which comprises the starch-(meth)acrylate graft copolymer above, water absorbing agent, reactive monomer, surfactant and material matrix. Further, sealing articles and packers prepared from the above oil swellable material and oil- and water-swellable material are also provided.