BC Transit – Air Brake Course

Review Questions Section Six (Tractor-Trailer)
1) Why is a tractor-trailer unit sometimes referred to as a “semi-trailer?”
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2) What is the purpose of a two-way check valve?
3) Why should the glad hands be protected when not in use?
4) How can an operator control the trailer brakes independently from the tractor brakes?
5) Can the application pressure delivered to the tractor brakes exceed the pressure delivered to
the trailer brakes?
6) Can the application pressure to the trailer brakes exceed the application pressure delivered to
the tractor brakes?
7) What are three ways of testing the emergency function of the emergency relay valve?
1) because 6) 7) Yes. close This the some supply can be of valve; advantages the weight break at of the times the supply trailer of poor line; is carried road break conditions the by the service tractor line
2) 3) 4) 5) No. by delivers to and keep use The make of them higher two-way a service hand clean pressure check valve and brake free derived valve application: of will debris from not and two trailer allow damage sources should this dynamite in all
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