Oil Hydraulics & Pneumatics(Department Elective - I) — Summer 2019

State the Pascal’s law. Explain the principle of Bramah’s press principle.

Draw the circuit of a simple hydraulic system, in standard symbols, and explain briefly the function of its basic elements.

Classify the pumps used for the hydraulic system and explain external and internal gear pump with neat sketches.

Distinguish between Hydraulic system & Pneumatic system.

What is the influence of following properties of hydraulic fluid on hydraulic systems?

Bulk Modulus (ii) Demulsibility (iii) Foaming tendency (iv) Volatility

What is the purpose of the filter in a hydraulic system? Where is it located in hydraulic circuit?

Write a short note on fire resistant and bio-degradable oils.

State salient functions of oil reservoir. Draw hydraulic symbol of a power pack.

State different types of Accumulator. Explain one in detail.

What is Hydrostatic transmission? Explain the change in torque, power and speed by hydraulic motor with different combination of motor and pump. Give its applications.

How does a pressure relief valve differ from a pressure reducing valve?

What is pressure compensated flow control valve? How does pressure compensation take place?

State and explain four main center conditions of 4/3 spool type direction control valve. Draw hydraulic symbols of each position for 4/3 solenoid operated spring centered direction control valve.

Give difference between Meter-in and Meter-out circuit.

Draw a schematic of a swash plate axial piston pump. Explain briefly its working and construction.

Explain the difference between regenerative and sequence control circuit for hydraulic control with neat sketch and suitable example.

What are different sources of heat generation and what is the effect of heat generated in hydraulic system.

Discuss the role of automation in pneumatic and hydraulic control systems.

Explain construction and operation of shuttle valve and twin pressure valve. Illustrate their application through a typical pneumatic circuit.

Write a short note on the Quick Exhaust valve.

Draw the detailed symbol of FRL unit. Explain any two component of the same in detail

Explain construction and operation of time delay valve. Illustrate its application in setting delay in closing time through a typical pneumatic circuit.

Explain ‘cushioning’ of pneumatic cylinder.

Explain cascade system for circuit design using assumed sequence.

In a press stamping operation to be performed using a stamping machine. Before stamping, work-piece has to be clamped under stamping station. Then stamping tool comes and performs stamping operation. Work-piece must be unclamped only after stamping operation.