Millwright 2Nd Year Hydraulic Pumps And Actuators Part B

Front 1

What is a double acting cylinder

Back 1

A cylinder that exerts force in both directions

Front 2

Which seals are contained in the rod bushing

Back 2

Rod wiper seals and pressure seals

Front 3

What is caused by failed rod seals

Back 3

Dirt and air get into the system

Front 4

Which type of piston rings would you use if no creep could be tolerated?

Back 4

Synthetic

Front 5

State two reasons for using cast iron piston rings

Back 5

Higher temperatures

Higher pressures

Front 6

Under what operating conditions would you use cylinder cushions

Back 6

When the load can force the piston to hit the end of the cylinder

Front 7

When would you require a cushion bypass

Back 7

If the cylinder is loaded as it begins its stroke

Front 8

When would you need a stop tube

Back 8

When the rod has a long extension with some side load

Front 9

Why is an ORB fitting preferable to a tapered thread fitting

Back 9

It causes less stress and distortion

Front 10

Should you normally install a cylinder with the ports at the top or at the bottom

Back 10

At the top

Front 11

Why is it important to align a cylinder with the load to which it is attached

Back 11

To avoid undue wear on the cylinder walls and on the seals

Front 12

What is the most costly result of leaks in a cylinder

Back 12

Dirt and air gets sucked into the system and damages components throughout the system

Front 13

If you rebuild a gear motor with new parts and you find that it turns freely by hand, what is the problem with the motor

Back 13

The gears and casing are fit too loosely

Front 14

Why should you check the return line filter and magnet (if a magnet is used) after you have run a new or rebuilt motor for the first time

Back 14

Metal is removed from the casing during break-in

Front 15

On which type of gear motor must you set the timing

Back 15

The orbiting gear motor

Front 16

Should you be able to slide the rotor and rollers together easily on a roller vane gerotor or should they be difficult to assemble

Back 16

Very difficult to assemble

Front 17

Which additional parts are found in vane motors that are not normally found in vane pumps

Back 17

Springs under the vanes

Front 18

List two ways that the swash plate angle affects the performance of an in-line axial piston motor

Back 18

Speed

Torque

Front 19

When you change a valve assembly on a radial piston motor, why must you mark the position of the drive coupling on the motor and on the valve as soon as you remove the old valve

Back 19

To ensure that the valve is correctly timed

Front 20

How can you change the displacement of a cam-type radial piston motor

Back 20

Change the cam ring for one of a different size

Front 21

Which type of cylinder is used in a hydraulic jack

Back 21

A ram

Front 22

What dangerous condition can develop if you shut off the cushion valve at the rod end of a cylinder that has a load pulling on it?

Back 22

Pressure intensification can occur

Front 23

How can you detect an internal leak in a cylinder

Back 23

By hot spots

Front 24

why is it best to install a cylinder with the ports at the top

Back 24

This allows you to bleed the air out after installation

Front 25

what two things should you look for to be sure that you have received a motor and not a pump by mistake

Back 25

Motor designation on the nameplate

M prefix in the model number

Front 26

What happens if you try to start up a vane motor without the springs in it

Back 26

Fluid bypasses the vane tips and the rotor would not turn

Front 27

What happens if you do not time a piston motor correctly

Back 27

It runs in reverse

Front 28

If the supply is normal to a radial piston motor, but it runs slower than normal, what should you check first

Back 28

The condition of the valve

Front 29

What is the operating principle of any hydraulic motor

Back 29

Fluid pushes on vanes, gear teeth or pistons to turn the drive shaft

Front 30

Which three types of motors are used for low speed and high torque

Back 30

Radial piston

Cam-type piston

Roller vane gerotor

Front 31

Which type of motor can only turn part of a rotation

Back 31

A limited rotation motor

Front 32

Which type of limited rotation motor can be used for clamping

Back 32

Cylinder with bell crank

Front 33

Which three specifications determine the torque in a motor

Back 33

Inlet pressure

Surface area of the motor elements

The radius of the rotation

Front 34

What does a decrease in mechanical efficiency indicate

Back 34

An increase in internal friction

Front 35

What does a decrease in volumetric efficiency indicate

Back 35

Internal leakage

Front 36

On which two factors does motor speed depend

Back 36

Displacement

Flow rate