Check air valve shall comply with the following provisions

Check air valve shall comply with the following provisions?      ; 1, opening and closing the flexible, close when should be tight; 2, the valve blade of the shaft, the hinge should be used not easy to rust material production, ensure the rotation is flexible, durable; 3, the valve plate strength should be guaranteed under the maximum load pressure without bending deformation; 4, the level of the installation check air valve should be a reliable balance adjustment mechanism. Check number: by category, batch sampling 10%, not less than 1, a. Inspection method: observation, scale, manual operation test and verification of the product certificate.