The single-line lubrication system is composed of a supply unit, a single-line distribution unit, a pressure monitoring unit, a
reversing unit, pipeline accessories, and a control unit. The single-line lubrication system transports the lubricant to the single-line distribution unit by a main grease pipe; each single-line distribution unit ser ves only one lubrication point; the displacement (the displacement of some single -line distribution units can be pre-set) is adjustable to provide accurate doses of lubricants. The difference between the single-line lubrication system and the progressive lubrication system is that the single-line system needs to be equipped with a pressure monitoring unit and a reversing unit; the control unit switches the pressure relief grease circuit by recognizing the pressure signal of the main grease pipe, and then completes the lubrication process. The single-line system is mainly used by medium-sized equipment that requires continuous and centralized lubrication.