Braking air cylinder for engineering machinery braking system

The invention discloses a braking air cylinder for an engineering machinery braking system. The braking air cylinder for the engineering machinery braking system comprises a cylinder barrel (3), an end cover (1), a braking spring, a piston and a piston rod; an annular groove is formed inside a rounded hole in the end portion of the cylinder barrel (3); steps are arranged on excircle surface of the end cover (1); the external end of the end cover (1) is a small excircle section and the internal end is a large excircle section; the large excircle section and an inner hole of the cylinder barrel (3) are formed into sliding fit; a circular-ring-shaped steel cable baffle ring (2) is arranged inside the annular ring; the inter diameter of the circular-ring-shaped steel cable baffle ring is less than the diameter of the inner hole of the cylinder barrel (3); the end cover (1) step surfaces are in contact with the steel cable baffle ring (2); the cylinder barrel (3) and the end cover (1) are connected through welding at the external end of the cylinder barrel (3). According to the technical scheme, the braking air cylinder for the engineering machinery braking system has the advantages of eliminating fault risks caused by poor welding quality due to the fact that the end cover of the braking air cylinder bears braking force is mainly concentrated on the steel cable baffle ring and improving the product safety and reliability.