Failure & Fluid Analysis

Question 1

Fluid analysis involves?

Answer 1

The identification of the physical properties and all the elements contained in the sample of used fluid

Question 2

Regular fluid testing generates data trend lines that can indicate? (3)

Answer 2

Wear rates of internal components
Rate of product deterioration and additive depletion
Amount and type of external contamination

Question 3

Random fluid analysis is known as?

Answer 3

Spot checking

Question 4

A good oil analysis report will provide information regarding 3 major areas, which are:

Answer 4

Deterioration of the oil itself, either the physical properties or additives
The amount of ppm and type of wear particles in oil
The presence of foreign contamination

Question 5

Viscosity

Answer 5

Resistance to flow

Question 6

A increase in viscosity can be caused by?

Answer 6

Contamination by product with higher viscosity
Thickening of the oil base due to contamination or high operating temperatures
Extended drain intervals

Question 7

Flash point

Answer 7

Is commonly used to indicate contamination by light hydrocarbons

Question 8

Acid number

Answer 8

provides useful info regarding the accumulation of combustion products and their reaction with various metallic surfaces and/or additive packages

Question 9

What substances indicate that anti-freeze may be present in oil?

Answer 9

Glycol

Sodium and boron when found together

Question 10

Extreme pressure agents in oil and grease commonly use what element?

Answer 10

Zinc

Question 11

Exhaust analysis

Answer 11

Is most often related to pollution standards

Question 12

Case hardening

Answer 12

A specialized process where only the surface layers of the steel are treated by methods including carbonizing, Carbon-nitriding and nitriding

Question 13

Cost of hardness

Answer 13

Hardness and resist to wear are gained at the expense of toughness required to take shock loads

Question 14

Fatigue fracture

Answer 14

Happen after several loading cycles occur over time and within normal spec. Will produce light coloured, smooth fracture surfaces with visible beach marks.

Question 15

Brittle fractures

Answer 15

Occur when a part suddenly breaks as the result of a shock or impact load. the sudden fracture produces a rough fracture surface with none or very little deformation

Question 16

Ductile fractures

Answer 16

Are caused by a single application of high shear stress. The surface of a ductile fracture will reveal plastic deformation as the molecules slipped past each other during shear

Question 17

Adhesive wear

Answer 17

Results from the formation and separation of minute atomic surface bonds at the molecular level of the surface. Small welds that were tore apart

Question 18

Abrasive wear

Answer 18

Is the scraping stress created by particles caught between 2 moving surfaces. Scratches, cuts and gouges appear without evidence of hot spots

Question 19

Surface fatigue wear

Answer 19

Occurs when surface cracks and pitting develop as a result of alternating the type of load stress applied to the surfaces. As the load is applied and released the molecules on surface shift and eventually break.

Question 20

True brinelling wear

Answer 20

Is identified as tiny indentations on the bearing race (microscopic). Visible line in the bearing race

Question 21

False brinelling

Answer 21

Material wear or removal that occurs over time from vibration without lubricant.

Question 22

Corrosive wear

Answer 22

Involves a chemical or electrochemical reaction between surfaces and the surrounding mediums

Question 23

Erosive wear

Answer 23

Involves the removal of material from a surface by high velocity particles in a fast moving fluid by the result of cavitation. Will appear as pits or notches with laser precision

Question 24

Tension

Answer 24

Is the stress placed on a component by forces that tend to elongate the component.

Question 25

Where are tension breaks usually found?

Answer 25

On components used to connect components or those used to transfer pulling forces.

Question 26

Tension break characterization

Answer 26

An increase in the longitudinal dimension of the member and a reduction on the cross-sectional dimension near the fracture

Question 27

Compression stress

Answer 27

Results when an applied force tends to compress the component, the resulting distortion normally occurs at 90 deg. to line of force

Question 28

Torsion stress

Answer 28

Stresses found rotating components

Question 29

The causes of metal component failures are categorized under what 4 major groupings?

Answer 29

Equipment operation including maintenance
Installation
Manufacture
Design

Question 30

Fluid analysis info is best utilized under what maintenance program?

Answer 30

Predictive

Question 31

T/F The higher the carbon content of steel the more malleable it will be?

Answer 31

False

Question 32

A metal fracture that indicates several beach marks and a final fracture area, is best described as?

Answer 32

A fatigue fracture

Question 33

A metal fracture that indicates sudden fractures following the molecular boundaries of the material, is best described as?

Answer 33

A brittle fracture

Question 34

3 classifications of stress found in mechanical parts of equipment are?

Answer 34

Tension
Compression
Torsion

Question 35

High wear of brass bushings would be indicated in an oil analysis as high PPM of?

Answer 35

Copper and Zinc

Question 36

Dust and dirt left inside an engine or housing during repair will be indicated in an oil analysis as?

Answer 36

Silicon