In the pneumatic braking system of a truck, what is the function of the drain valves located on the air tanks?

Question

DentroTest · Accepted Answer

When air taken in from outside is compressed, the moisture it contains condenses as it cools and accumulates in liquid form at the bottom of the air tanks or storage reservoirs. The function of the bleed or drain valves (manual or automatic) is to drain that water periodically in order to avoid serious faults, such as internal corrosion of the pneumatic components, loss of usable air volume and the risk of freezing in winter, which could block the braking system. Connecting the outlets to the semi-trailer is not their function, because that connection is made with coupling heads; and removing air bubbles is a feature of hydraulic brakes, not pneumatic ones.

In the pneumatic braking system of a truck, what is the function of the drain valves located on the air tanks?

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