Operating Principle and Features: The series SYF roots vacuum pump is with overflow valve. The figure-of-eight rotors are counter-rotating at a continual velocity within the pump housing for suction and exhaust of gasoline. Two rotors are supported by two bearings and synchronized by a gear, which ensures these two rotors in specific relative positions. They’re near to each other and to the housing with no actual contacting, so lubrication is needless from the working housing. The very carefully balanced operating elements and substantial precision bevel wheels ensue the pump be operated stably and continuously below the issue of high-pressure difference. Dynamic seal aspect employs our patent technologies and imported oil seals, the vibration quantity of shaft over the shaft seals is managed to much less than 0.02mm. A gravity valve is put in between the suction and exhaust part of the pump. The function on the gravity valve is as follows, once the strain variation concerning the suction and exhaust component is more than the bodyweight from the valve, the valve opens immediately, which tends to make the strain variation normally retain in a fixed controllable value, the value is the allowable highest stress big difference to ensure the pump operate commonly and so that in actual fact, the roots vacuum pump with overflow valve can be a form of overload self-protective pump. Series SYF roots vacuum pump with overflow valve has substantially greater velocity at relatively reduce inlet strain and it’s possessed overload self-protective perform. Because it can be a pump of dry clearance seal construction, if a particular pumping velocity charge 15 and an ultimate vacuum should be obtained, it’s important to supply a lower inlet pressure for decreasing the back movement, hence, a pump must be backed in use, roots vacuum pump should be began quickly immediately after its inlet pressure reaches a permissible value for economization. It is actually permit to select diverse sorts of pump since the backing pump for factual prerequisites, this kind of as oil seal pump and liquid ring vacuum pump. When pumping the fuel containing significant level of vapor, the liquid ring vacuum pump could be the suitable backing pump.