Air brake system valve for trailers

The invention relates to an air brake system valve (10) comprising retaining ring (24), and spring top bearing lower casing (21) and spring top bearing top casing (22) which provide sealing by covering the valve seat together with the valve centering device (17) and seal O-ring (20) on the control valve (16) which enables flow of air from inlet port (12) to the air exhaust port (13), characterized in comprising a special casing (11) that harbors the live parts of said valve (10) and enables linking of the valve (10) on the vehicle; a front cover (25) covering the top part of the casing and exhausting air from said valve (10) together with camoperated exhaust (23); an exhaust (26) that enables exhausting exhaust air from said valve (10); a drive shaft (29) driven within said valve (10) and operating the piston (28) and the control valve (16), and a rear cover (30) covering the bottom part of said valve (10).