🔍 Key Concepts

• Study how air-operated clutch glands work in a reversing reduction gear like the one in the illustration. • Think about what happens to the friction blocks (shoes) when the rubber gland is inflated vs. deflated. • Consider whether both clutches can be pressurized at the same time, and what happens to the idle clutch while the other is engaged.

💭 Think About

• Look closely at the illustration and imagine the shaft turning ahead: what must happen to the ahead gland and its friction blocks to transmit torque to the gear drum? • For the clutch that is NOT engaged, ask yourself: does it still rotate with the assembly, and are its friction blocks touching or clear of the drum? • If both glands were inflated together, what would that do to the gearbox output and to the ahead/astern selection?

✅ Before You Answer

• Verify which statements correctly describe inflation/deflation of the rubber glands and the position of the friction blocks relative to the drum. • Check whether an idle clutch’s friction blocks should ride on the drum or be clear of it to avoid drag and heating. • Confirm that the control air system is arranged so only one clutch gland can be engaged at a time, to prevent conflicting ahead/astern thrust.