Abstract: An intelligent self-sequencing rice seedling throwing machine is provided. A seedling box, a first belt seedling conveyor, a second belt seedling conveyor, and a blower are mounted on a chassis. A seedling picker is installed inside the seedling box and is located at the seedling outlet of the seedling box. The first belt seedling conveyor is located below the seedling outlet of the seedling box. The second belt seedling conveyor is located below the first belt seedling conveyor. An air outlet of the blower is located below the point where seedlings fall from the end of the second belt seedling conveyor. A first seedling combing device is installed above the first belt seedling conveyor. Seedlings pass through the gap between the first belt seedling conveyor and the first seedling combing device and fall onto the second belt seedling conveyor.

Abstract: A polycrystalline diamond compact drill bit includes a steel body connector and a matrix crown. The matrix crown is provided with multiple main blades extending axially. A rear end surface of the matrix crown is provided with a connecting block projecting backwardly. A front end surface of the steel body connector is provided with a connecting groove having a shape matching a shape of the connecting block. The connecting block is inserted into the connecting groove to form an interference fit with the connecting groove. The rear end surface and the front end surface are fitted to each other. The periphery of the connecting block is provided with an inner positioning hole. A periphery of the steel body connector is provided with an outer positioning hole penetrating into the connecting groove at a position corresponding to the inner positioning hole.

Abstract: A drill bit nozzle includes a nozzle body, a channel in the nozzle body, and a nozzle outlet arranged at an end of the nozzle body and in communication with the channel. The nozzle outlet is a strip-shaped outlet configured to eject a sheet-like jet flow. Since the nozzle outlet of the drill bit nozzle is a strip-shaped outlet, the nozzle outlet is able to eject a sheet-like jet flow. When the drill bit nozzle is applied to a PDC drill bit, the drill bit nozzle can uniformly eject a drilling fluid onto each cutting tooth, which ensures that the cutting teeth in the drill bit may obtain good cooling and chip removal effects, while avoiding excessive concentration of the jet flow from the drill bit nozzle which may erode the cutting teeth, thereby prolonging the service life of the drill bit.

Abstract: A polycrystalline diamond compact drill bit is provided according to the present application, including a steel body connector and a matrix crown. The matrix crown is provided with multiple main blades extending axially. A rear end surface of the matrix crown is provided with a connecting block projecting backwardly. A front end surface of the steel body connector is provided with a connecting groove having a shape matching a shape of the connecting block. The connecting block is inserted into the connecting groove to form an interference fit with the connecting groove. The rear end surface and the front end surface are fitted to each other. The periphery of the connecting block is provided with an inner positioning hole. A periphery of the steel body connector is provided with an outer positioning hole penetrating into the connecting groove at a position corresponding to the inner positioning hole.

Abstract: The present application discloses a drill bit nozzle, which includes a nozzle body, a channel in the nozzle body, and a nozzle outlet arranged at an end of the nozzle body and in communication with the channel. The nozzle outlet is a strip-shaped outlet configured to eject a sheet-like jet flow. Since the nozzle outlet of the drill bit nozzle is a strip-shaped outlet, the nozzle outlet is able to eject a sheet-like jet flow. When the drill bit nozzle is applied to a PDC drill bit, the drill bit nozzle can uniformly eject a drilling fluid onto each cutting tooth, which ensures that the cutting teeth in the drill bit may obtain good cooling and chip removal effects, while avoiding excessive concentration of the jet flow from the drill bit nozzle which may erode the cutting teeth, thereby prolonging the service life of the drill bit.