Abstract: A flexible electroluminescent fiber for embroidery sequentially includes: metal core wires, a light-emitting layer, a transparent conductive layer, a filament, and a protective paint, wherein a quantity of the metal core wires is an even number, and the metal core wires are pasted together before being wrapped by the light-emitting layer; the light-emitting layer is coated with the transparent conductive layer; the protective paint and the filament are exterior to the transparent conductive layer; the metal core wires emit light through energizing; a diameter of the electroluminescent fiber is 0.1-0.3 mm, and a 20-36V safe voltage is applied for emitting light. The flexible electroluminescent fiber of the present invention has sufficient tensile force, and smooth and soft surface. Appearance and hand feeling of the present invention are the same as those of clothing textile fibers.

Abstract: A split roller cone and polycrystalline diamond compact (PDC) composite drill bit, including a PDC bit module, a split roller cone bit module, and a drill bit body module. The split roller cone bit module has split structure, and during the operation, the lower roller cone body and the upper roller cone body revolve with the drill bit, and rotate around the axle neck of the palm respectively, thereby achieving the task of scraping and breaking rocks. The tooth scraping efficiencies of the small-end ring gear and the middle ring gear are improved. The split roller cone bit module, the PDC bit module, and the drill bit body module can be mass-produced. The split roller cone bit module and the PDC bit module can be quickly assembled and disassembled with the drill bit body module and different sizes of PDC bit modules are assembled with the bit body module.

Abstract: A split roller cone and polycrystalline diamond compact (PDC) composite drill bit, including a PDC bit module, a split roller cone bit module, and a drill bit body module. The split roller cone bit module has split structure, and during the operation, the lower roller cone body and the upper roller cone body revolve with the drill bit, and rotate around the axle neck of the palm respectively, thereby achieving the task of scraping and breaking rocks. The tooth scraping efficiencies of the small-end ring gear and the middle ring gear are improved. The split roller cone bit module, the PDC bit module, and the drill bit body module can be mass-produced.