[Tianjin Jinzhong Ji HVAC purification equipment to recommend the star product - check] opening and closing pieces by medium flow and strength to turn itself on or off, in order to prevent the media called backflow check valve. Check valves are automatic valves, mainly used for medium-way flow of pipeline smoke damper only allowed media to flow in one direction, in order to prevent accidents. Check valve according to the structure can be divided into lift check valve, swing check valve and butterfly valve in three ways: 1 is divided into vertical and horizontal lift check valves. 2. Swing check into a single lobe, double valve type and Orange Peel three. 3. butterfly valve for straight-through. Several more formal check valve in the connection can be divided into threaded, flanged, welded connections and wafer four. [Tianjin Jinzhong Ji HVAC purification equipment to recommend the star product --280 degrees] damper damper choice points 1. The main control parameters for the selection and specification. 2. damper suitable for ventilation and air conditioning systems, in addition to public buildings, kitchen hood system with damper valve, operating temperature of 150 ℃, the general ventilation and air conditioning systems with fire dampers operating temperature of 70 ℃. 3. The damper is suitable for pipe ventilation, air conditioning or exhaust system, the scope and application of the basic functions in Table 1. 4. The selection of valve should pay attention to the function of the valve, normally open or normally closed, shut down automatically open, close the open hand, manual reset, signal output, remote control and other requirements. 5. If the valve and fan interaction should be used with double micro-switch device. 6. The valve blade should be multi-page exhaust port valve plate thickness of 2 ~ 6mm pressure outlet valve, the valve is non-combustible material, rotating parts should be corrosion-resistant metallic materials, and flexible rotation. Shall not be less than the thickness of the valve housing 2mm. Yi Rong parts shall comply with recognized standards of the fire department. Inner plate valve exhaust port valve _ _ Tianjin Jinzhong Ji damper manufacturer provided by Tianjin Jinzhong Ji HVAC purification equipment. Tianjin Jinzhong Ji HVAC purification equipment Limited (www.Jzjnt.com) strong, credible, in Tianjin fans, ventilation equipment industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead the group into the brilliant and you work for a better future!