Valve arrangement

A valve arrangement for use in a rail brake system having wheel slide protection. The valve has an inlet port 1 supplied from a distributor or load relay valve and an outlet port 2 leading to at least one brake cylinder. The valve arrangement comprises a hold diaphragm 3 adapted to control air flow between inlet port 1 and the outlet port 2 and a vent diaphragm 10 adapted to control air flow between the outlet port 2 and the exhaust. The hold diaphragm 3 is controlled by a first solenoid 6 and the vent diaphragm 10 is controlled via a further diaphragm 12, which further diaphragm 12 is controlled by a further solenoid 13. The volume of air on the control side of the vent diaphragm 10 is three times greater than the volume of air the further solenoid 13 vents from the further diaphragm 12. The valve arrangement may be used in a railway brake system having slide protection.