Abstract: A pressure compensation device with an accumulator group for controlled pressure drilling includes an electrical flat valve, a check valve, an accumulator group, a flanged pup joint and a support base. The electrical flat valve is connected to the check valve and is mounted on a top surface of the support base. The accumulator group mounted on the whole support base is a pre-storage pressure compensation device for controlled pressure drilling, and is located at a downstream position of the check valve. The liquid inlet end of the accumulator group is connected to the check valve, and the liquid discharge end is connected to the flanged pup joint.

Abstract: The present application relates to the technical field of smart devices. A rotating shaft module, a folding assembly, and an electronic apparatus. The rotating shaft module includes a mounting housing; two rotating shafts, arranged opposite to each other and rotatably connected to a mounting housing, respectively, and each of the two rotating shafts being configured to slide relative to the mounting housing in an axial direction; an elastic assembly sleeved on each rotating shaft, abutting against the mounting housing, and configured to apply a force to each of the two rotating shafts along a direction opposite to a sliding direction, such that each of the two rotating shafts is kept stable; and a first connecting member, threaded to each of the two rotating shafts.

Abstract: A polyurethane composite element has one or more gaps containing a polyurethane foam. The polyurethane foam has a density of 16-40 kg/m3 and a closed cell proportion of 50-90% determined according to ASTM D6226-2010 Standard Test Method. The polyurethane foam is formed by applying a polyurethane composition into the gaps in situ. A process for producing a polyurethane composite element is also described.

Abstract: The present invention provides a process for preparing a polymer material filled composite element, comprising the steps of: i) providing a partially closed space, wherein a polyurethane foam is disposed at least at part of the periphery of the space to restrain the flow of the polymer material resin, and the polyurethane foam is formed by in situ application of a polyurethane composition and has an air flow value of greater than 1 L/min as determined by ASTM D3574 test; ii) applying the polymer material resin into the space and curing the polymer material resin to form a polymer material that fills the space.

Abstract: A polyurethane composite element has one or more gaps containing a polyurethane foam. The polyurethane foam has a density of 16-40 kg/m3 and a closed cell proportion of 50-90% determined according to ASTM D6226-2010 Standard Test Method. The polyurethane foam is formed by applying a polyurethane composition into the gaps in situ. A process for producing a polyurethane composite element is also described.