CH4
Chapter 4 · Overhead cranes
Tutorials 4.1 and 4.2 of the booklet, then the course's worked examples on hoist and trolley sizing, duty, braking and anti-sway (Lab IV).
7 exercises
- 01Sizing a crane hoist motor and braking resistorRaising power, motor power, gear ratio and torque, the power returned when lowering, and the braking resistor. · 6 questionsTD 4.1Not started
- 02Comparison of crane drive technologiesDC thyristor or Ward-Leonard drives against AC vector drives, criterion by criterion, and a recommendation. · 4 questionsTD 4.2Not started
- 03Hoist against trolley drive sizingThe hoist needs continuous power in both directions; the trolley needs a short burst of accelerating force. · 3 questionsCourse §4.1.1Not started
- 04Load spectrum factor of a craneSpectrum factor k_p with the cube law, and the spectrum class L1 to L4. · 2 questionsCourse §4.1.2Not started
- 05Braking resistor for an intermittent hoistThe resistor absorbs the peak lowering power, but its continuous rating follows the duty cycle. · 3 questionsCourse §4.2.1Not started
- 06Sizing the holding brake of a hoistBrake torque on the motor shaft and on the drum with course eq. 4.4, the efficiency multiplying. · 2 questionsCourse §4.2.2Not started
- 07Anti-sway pulse timingPendulum period, two-pulse spacing, and why a shorter rope needs a new tuning. · 3 questionsCourse §4.3.3Not started