2ND 21

Question 1

A strainer is called a _______ filter.

a) Fine
b) Coarse
c) Media
d) Absorbent

Answer 1

b) Coarse

Question 2

A particle one micron in size equals _______ filter.

a) .000583
b) .7053
c) .00275
d) .000039

Answer 2

d) .000039

Question 3

A filter designed to signal the operator when the element needs cleaning is called a(n) __________ filter.

a) Circulating
b) Off-line
c) Absorbent
d) Indicating

Answer 3

d) Indicating

Question 4

Three general areas for locating a filter are inlet, pressure and _________ lines.

a) Pilot
b) Return
c) Flow
d) Relief

Answer 4

b) Return

Question 5

What type of filter element provides precise control of pore size?

a) Cylindrical
b) Sub-plate
c) Surface
d) Pleated

Answer 5

c) Surface

Question 6

Filtering materials are classified as absorbent or ________ .

a) Mesh
b) Adsorbent
c) Fiber
d) Depth-type

Answer 6

b) Adsorbent

Question 7

What type of filter passes the entire flow entering its inlet through the element?

a) Proportional flow
b) Indicator type
c) Full flow
d) Reverse flow

Answer 7

c) Full flow

Question 8

The smallest particle an eye can see is approximately ________ microns.

a) 25
b) 40
c) 50
d) 75

Answer 8

b) 40

Question 9

Hydraulic circuit components fail as a result of contamination and _________ .

a) Design
b) Phase
c) Static
d) ISO

Answer 9

a) Design

Question 10

If the fluid within the hydraulic pump clearances becomes heavily contaminated, ___________ will probably occur.

a) Cavitation
b) Fatigue
c) Aeration
d) Seizure

Answer 10

d) Seizure

Question 11

Which of the following is not a mechanism of wear?

a) Adhesion
b) Filtration
c) Fatigue
d) Cavitation

Answer 11

b) Filtration

Question 12

Contamination blockage which prevents and then allows a solenoid spool to shift is called a _______ failure.

a) Degradation
b) Catastrophic
c) Transient
d) Critical

Answer 12

c) Transient

Question 13

In increase in the pressure differential across a filter will cause a(n) _______ in power consumption.

a) Increase
b) Half-wave
c) Decrease
d) Beta ratio

Answer 13

a) Increase

Question 14

When specifying the correct filter for a given application, which of the following would not be considered?

a) Weight of particles to be held
b) Flow rate capacity
c) Flow sampling method
d) Pressure drop through element

Answer 14

c) Flow sampling method

Question 15

Which is not a source of contamination in a hydraulic system?

a) Ingressed
b) Entrained
c) Internally
d) Built-in

Answer 15

b) Entrained

Question 16

The preferred location for dynamic sampling is directly _______ of the return line filter.

a) Downstream
b) Midstream
c) Center
d) Upstream

Answer 16

d) Upstream

Question 17

After hydraulic system assembly, tubing must not be soldered, welded or ________ .

a) Flared
b) Threaded
c) Brazed
d) Plugged

Answer 17

c) Brazed

Question 18

When transferring clean oil, the transfer pump should be equipped with a _________ filter.

a) Beta
b) Coarse
c) 5 micron
d) Mesh

Answer 18

c) 5 micron

Question 19

Filters that can trap much smaller particles than inlet line strainers are _______ _______ filters.

a) Pressure line
b) Return line
c) Off line
d) Pilot line

Answer 19

a) Pressure line

Question 20

The higher the sieve or mesh number the _________ the screen.

a) Thicker
b) Finer
c) Thinner
d) Coarse

Answer 20

b) Finer

Question 21

To test for filter material compatibility, the filter element is immersed for ____ hours in system fluid.

a) 59
b) 63
c) 84
d) 72

Answer 21

d) 72

Question 22

In cylindrical shaped filter elements, ________ tubes are used to support the media against pressure differential.

a) Stainless
b) Flared
c) Perforated
d) Bypass

Answer 22

c) Perforated

Question 23

Hydraulic fiberglass filter elements tend to have a _________ filtering structure.

a) Stainless
b) Mesh
c) Surface
d) Pleated

Answer 23

d) Pleated

Question 24

To eliminate the possibility of filter element collapse, a __________ valve is used.

a) Bypass
b) Inlet
c) Rotary
d) Check

Answer 24

a) Bypass

Question 25

To monitor initial and subsequent levels of contamination _______ points must be provided.

a) Filter
b) Sampling
c) Static
d) Dynamic

Answer 25

b) Sampling