Hydraulic/Machinist Exam

2. Describe the type of pump used in this circuit and its function.

3. What component sets the maximum system pressure and what is the pressure.

4. Using the formula:    and data on the drawing, how much power would we need to run the system @ 350bar?

 

5. Using the data on the drawing calculate the displacement in cc/rev of the pump, where motor speed is 2800 rpm and flow is 46 LPM?

6. What testing equipment would you use to check the performance of the pump?

8. Which of these pressure plates has suffered severe damage from aeration and is beyond repair?

9. The primary purpose of a fluid power system is to transmit ___________ from one location to
another.

10. A fluid power system requires an input source of power. This power source may be
_______________ or________________

11. The power is then converted to an equivalent amount of fluid power by means of a _________________ or _______________

12. If the fluid is under pressure but not moving, such as a cylinder stalled against a load, only __________ is being transmitted.

13. The cylinder shown here is a ______________________.

14. Movement in a double-acting cylinder takes place when there is a sufficient difference in pressure
between the opposite sides of the piston.

15. Cylinders are "constant horsepower" devices. They can produce equal horsepower either while
extending or retracting, though the power may be at a different ratio of speed and force.

16. The amount of force, in pounds, that a cylinder can produce can be calculated by multiplying the
gauge pressure (PSIG) times the square inch area of the piston surface that it is working against. This is
an application of Boyles’ Law.

17. Hydraulic cylinders normally have larger rods, with the rod area being as much as 50% of the full
piston area. Often rod end area is disregarded in calculations.

18. The cylinder shown here is operating under a pressure of 80 PSIG. What is the force on extension?

19. As a rule-of-thumb, a gear pump requires a 40-micron filter and vane pumps require a 25-micron filter.

20. Most of the failures in hydraulic systems show similar symptoms: a sudden or gradual loss of high
pressure, resulting in loss of power or speed in the cylinders.

21. The most frequent trouble encountered in a hydraulic system is __________________.

22. If the gauge pressure does not rise above a low value, say 100 PSI, and if the volume of flow does not
substantially decrease as the relief valve adjustment is tightened, the relief valve is probably not at
fault, and should be cleaned or replaced.

23. If the oil flow substantially decreases as the relief valve adjustment is tightened, and if only a low or moderate pressure can be developed, this indicates pump problems.

24. If the pump is delivering full pressure when operating across the relief valve, both pump and relief
valve should be considered good, and the trouble is further downstream. The cylinder should be tested
first.

25. The valves used to control the flow of fluid between a hydraulic pump or air compressor and the
actuating device can be grouped into three classifications. They are:

26. Directional control valves are used to route the flow of fluid and to start and stop the flow without affecting the flow rate.

27. The symbol shown here is a _____________.

28. The symbol shown here is a _____________.

29. If a cylinder barrel bore is damaged over the whole length, what process would you use to
rectify this:

31. What precautions that should be observed when using an angle grinder?

32. Name the symbol below

33. Name the symbol below

 

34. Name the symbol below

35. Name the symbol below

36. Name the symbol below

37. Name the symbol below

38. If the cylinder shown had equal pressure at ports A and B what would happen.

 

39. Select the part name to the drawing below

 

 

40. Select the part name to the drawing below

 

 

41. Select the part name to the drawing below