Working Principle and Features: The series SYF roots vacuum pump is with overflow valve. The figure-of-eight rotors are counter-rotating at a frequent speed within the pump housing for suction and exhaust of fuel. Two rotors are supported by two bearings and synchronized by a gear, which assures these two rotors in sure relative positions. They are close to to one another and to the housing without real contacting, so lubrication is needless within the operating housing. The carefully balanced working elements and large precision bevel wheels ensue the pump be operated stably and constantly underneath the problem of high-pressure big difference. Dynamic seal portion uses our patent engineering and imported oil seals, the vibration level of shaft over the shaft seals is managed to significantly less than 0.02mm. A gravity valve is set up between the suction and exhaust a part of the pump. The function of the gravity valve is as follows, once the stress variation involving the suction and exhaust portion is in excess of the weight with the valve, the valve opens instantly, which helps make the stress difference usually preserve in the fixed controllable value, the worth may be the allowable highest strain variation to be sure the pump get the job done generally and to ensure in actual fact, the roots vacuum pump with overflow valve is actually a kind of overload self-protective pump. Series SYF roots vacuum pump with overflow valve has substantially greater speed at comparatively decrease inlet strain and it’s possessed overload self-protective function. Since it is usually a pump of dry clearance seal building, if a certain pumping pace rate 15 and an ultimate vacuum must be obtained, it can be required to supply a lower inlet pressure for cutting down the back flow, thus, a pump have to be backed in use, roots vacuum pump really should be started out quickly soon after its inlet strain reaches a permissible worth for economization. It is allow to select distinctive types of pump as the backing pump for factual requirements, this kind of as oil seal pump and liquid ring vacuum pump. When pumping the gas containing large volume of vapor, the liquid ring vacuum pump will be the best backing pump.