The annular filter belt negative pressure filter is a kind of automatic grinding fluid purification equipment independently developed and manufactured by our company on the basis of absorbing foreign advanced technology and combining relevant technical requirements of our company's YK series grinding wheel gear grinding machine. The machine is widely used for purification and regeneration of cooling (lubricating) fluid of various CNC grinding machines, such as flat grinding, external grinding, grinding and gear grinding machines. It has the advantages of high degree of automation, less consumables, less oil in filter residue, accurate temperature control of coolant, etc. 