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Hand control for air springs
5th December 1969, Page 42
5th December 1969
Page 42
Page 42, 5th December 1969
— Hand control for air springs
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• Pressure in the air springs of the second steering axle of Atkinson twin-steer tractive units is now controlled by a manual light/ laden valve in the cab. In the "laden" position. the air springs are pressurized to 80 psi. reduced to 30 psi. in the "light" position.
The reduced pressure keeps the tyres in contact with the ground but provides extra weight on the driving axle to overcome wheel slip in low-adhesion conditions. Previously. there was automatic control of the air pressure, supplemented by an overriding manual control with which all the air could be exhausted but when drivers omitted to recharge the air springs after using the manual control, locking of the wheels when braking caused premature tyre wear.