The shaft clearance compensation design automatically adjusts the pump's displacement based on the set pressure. It has a built-in pressure regulator, so the system doesn't need an external pressure regulating valve. It features high efficiency, energy saving, safety and reliability. It works for grinding machines, automatic lathes, pressure machinery, leather machinery, shoe-makin... https://www.rectehydraulic.com/vane-type-pump-30-40-product/