Abstract: The present disclosure discloses a method for automatically identifying south troughs by improved Laplace and relates to the technical field of meteorology. The method includes the following steps: acquiring grid data of a geopotential height field; calculating a gradient field of the geopotential height field in an x direction; searching for a turning point where a gradient value turned from being negative to being positive, and cleaning the gradient field; calculating a divergence of the x direction to obtain an improved Laplacian numerical value L?; performing 0,1 binarization processing on the L? to obtain a black-and-white image and a plurality of targets of potential troughs, merging the black-and-white image and the plurality of targets of the potential troughs by expansion, recovering original scale through erosion, and selecting an effective target through an angle of direction of a contour and an axial ratio.

Abstract: An axle box suspension positioning device for a railway vehicle is provided, which includes a guide column assembly. The guide column assembly includes a fixed end connected to a frame of the railway vehicle, and a free end which is extendable and retractable from an opening of the axle box. An elastic positioning component is provided in the opening, and the elastic positioning component limits a movement of the free end along a running direction of the vehicle with respect to the frame. The arrangement of the elastic positioning component enables the axle box suspension positioning device to have a large positioning rigidity. A bogie having the axle box suspension positioning device is also provided.

Abstract: An axle box suspension positioning device for a railway vehicle is provided according to the present application, which includes a guide column assembly. The guide column assembly includes a fixed end connected to a frame of the railway vehicle, and a free end which is extendable and retractable from an opening of the axle box. An elastic positioning component is provided in the opening, and the elastic positioning component limits a movement of the free end along a running direction of the vehicle with respect to the frame. The arrangement of the elastic positioning component enables the axle box suspension positioning device to have a large positioning rigidity. A bogie having the axle box suspension positioning device is further provided according to the present application.

Abstract: A side frame for a bogie. Two longitudinal sides of the side frame are respectively provided with a supporting seat for connecting an end portion of a connecting rod, and the supporting seat is integrally formed with the side frame by casting. The supporting seat includes a supporting plate, a middle rib and a first side rib. The supporting plate is provided with a through hole. The connecting rod and the supporting seat are thread-connected via a conical pole which is fixedly provided in the through hole. The side frame reduces the welding processes, ensures the installation precision of the supporting seat, and enhances the strength of the supporting seat.

Abstract: A side frame for a bogie. Two longitudinal sides of the side frame are respectively provided with a supporting seat for connecting an end portion of a connecting rod, and the supporting seat is integrally formed with the side frame by casting. The supporting seat includes a supporting plate, a middle rib and a first side rib. The supporting plate is provided with a through hole. The connecting rod and the supporting seat are thread-connected via a conical pole which is fixedly provided in the through hole. The side frame reduces the welding processes, ensures the installation precision of the supporting seat, and enhances the strength of the supporting seat.

Abstract: A central suspension device, a wagon bogie and an express railway wagon, wherein the central suspension device is arranged between a frame and a bolster of the wagon bogie and comprises a rubber-metal pad spring group composed of at least two rubber-metal pad springs, a bottom end of each rubber-metal pad spring is connected with the frame, a top end of at least one rubber-metal pad spring of the rubber-metal pad spring group is connected with the bolster, and a gap exists between the top end of at least one rubber-metal pad spring and the bolster. The central suspension device has multiple stages of rigidities in the transverse and vertical directions, so that the different rigidities can be mutually shifted conveniently on the empty vehicle condition and the heavy-load condition of the vehicle, therefore, the central suspension device is applicable to express railway vehicles for safe and stable running.

Abstract: A freight car bogie and a freight car are provided. The freight car bogie includes two wheel set assemblies, side frames, and a bolster. The freight car bogie further includes a first connecting rod and a second connecting rod. The first connecting rod and the second connecting rod are crossed in an X form to pass through reserved holes at two sides of a belly of the bolster. The first connecting rod and the second connecting rod are separated from each other at a crossing portion. The first connecting rod includes a first end and a second end. The second connecting rod includes a third end and a fourth end. The first end and the third end are resiliently connected to one of the side frames and symmetrical about a center line of the bolster. The second end and the fourth end are resiliently connected to the other side frame and symmetrical about the center line of the bolster.

Abstract: A central suspension device, a wagon bogie and an express railway wagon, wherein the central suspension device is arranged between a frame and a bolster of the wagon bogie and comprises a rubber-metal pad spring group composed of at least two rubber-metal pad springs, a bottom end of each rubber-metal pad spring is connected with the frame, a top end of at least one rubber-metal pad spring of the rubber-metal pad spring group is connected with the bolster, and a gap exists between the top end of at least one rubber-metal pad spring and the bolster. The central suspension device has multiple stages of rigidities in the transverse and vertical directions, so that the different rigidities can be mutually shifted conveniently on the empty vehicle condition and the heavy-load condition of the vehicle, therefore, the central suspension device is applicable to express railway vehicles for safe and stable running.