Abstract: The application provides a method for controlling nitrogen in steelmaking by spraying hydrogen containing plasma, including: using a mixture of hydrogen rich gas and argon gas to generate hydrogen plasma for denitrification of molten steel during at least one of arc furnace smelting, ladle refining, VOD refining, and RH refining. The method for controlling nitrogen in steelmaking by spraying hydrogen containing plasma provided in the application can effectively remove nitrogen from the molten steel by spraying a mixture of argon gas and hydrogen rich gas into the molten steel through a hollow electrode and plasma torch, reducing electrode consumption and electricity consumption per ton steel, and also reducing arc radiation heat loss, improving heating rate, thereby shortening smelting time and reducing production costs.

Abstract: A lifting mechanism for gym equipment to provide height adjustment of the gym equipment and reduction of the thickness of the mechanism, having a bracket, a bearing rotational shaft, bearing wheels, a sleeve pipe, and a driver; the bracket is mounted to a gym equipment structural frame; the bearing rotational shaft is rotationally mounted between two ends of the bracket, a peripheral surface of the bearing rotational shaft is connected to linkage arms orienting to a same direction, and a wheel is mounted to each linkage arm; the sleeve pipe is pivotally connected to the bracket; the driver is pivotally connected to the bracket; an output end of the driver is a screw bolt; the screw bolt passes through the sleeve pipe.