Protein purification equipment

The invention discloses protein purification equipment. A threaded rod is arranged in a manner of being fixed relative to the position of a six-way valve sample injector and can freely rotate around the axis of the threaded rod; the threaded rod is sleeved with the driving sleeve in a threaded mode, and the driving sleeve can move in the axis direction of the threaded rod through a limiting device when the threaded rod rotates. The injector clamping sleeve is arranged in a manner of being fixed relative to the position of the six-way valve sample injector; the driving sleeve is over against a sample inlet of the six-way valve sample injector; the threaded rod is coaxially and fixedly connected with an output shaft of the stepping motor; the liquid uniform distribution plate covers the cross section of the main pipe in a sealing manner and is always kept horizontal, a plurality of through holes with the same aperture are formed in the liquid uniform distribution plate, and the through holes are in one-to-one c