
- The operating hydraulic circuit for a luffing cylinder for a deck crane is shown in the figure. Explain the purpose and describe the operation of EACH item A, B and C.
(10) Fig Q1
Answer

- With reference to a crane operated by a constant pressure hydraulic system incorporating unidirectional, fixed displacement pumps that run continuously, explain EACH of the following:
(a) the purpose of the accumulator;(2)
(b) how the hydraulic pressure is regulated;(2)
(c) how the speed and direction of the hoist motor is varied;(3)
(d) how the torque available from the hoist motor can be varied.(3)
1970’s NUS training Series Print Reading & Use
https://www.youtube.com/watch?v=ivGWhOv-QoI