403 - Contamination & Filtering

Question 1

Contamination is

Answer 1

The enemy to modern hydraulic systems.

Question 2

Types of Contamination

Answer 2

Solid
Liquid
Gas

Question 3

Solid contamination

Answer 3

Dirt
Metal from welding and grinding
Wear of pump

Question 4

Liquid contamination

Answer 4

Water from condensation

Question 5

Gas contamination

Answer 5

Entrained air from loose hose

Vaporize the oil at high temp

Question 6

At what size micron do we start testing?

Answer 6

15

Question 7

At what size do we start in removing?

Answer 7

5

Question 8

Human eye can only see down to how many microns?

Answer 8

40

Question 9

1 micron, micrometer =

Answer 9

.001 m

.0000039”

Question 10

What percent of all hydraulic oild is contaminated?

Answer 10

90% and you can’t see it.

Question 11

ISO/NAS Codes

Answer 11

Are the measure of particles/particulate per a specific volume of fluid

Question 12

28/18/11

Answer 12

28 would be the total # of particles
18 would be the # under 15 microns
11 would be the # under 10 microns

Question 13

Higher the Cleanliness #:

Answer 13

The dirtier the oil

Question 14

Sources of Contamination:

Answer 14

Built in during manuf. and maintenance.
Tank Leakage
Air through the breather
Dirty new oil - worst Problem
Pump wear
Piping Scale - piping needs to be honed after extruded
Dirt on rods due to broken seals

Question 15

What percent of wear and failure is contamination related?

Answer 15

70-90%

Question 16

Collapse Pressure

Answer 16

Point at which element filter media fails.

Question 17

Beta Stability

Answer 17

Beta Ratio remains at a relatively constant level at high pressure drops beyond ormal element operating ranges.

Question 18

Beta 100 Stability means:

Answer 18

Beta Ratio at the rated micron will not drop below Beta Ratio 100 until 250 psi is reached.

Question 19

Poor Beta Stability causes:

Answer 19

Significant loss of filter efficiency through element life.
Loss of Equipment.
Increased wear and component failure.
Increase in downtime.
Decrease in customer satisfaction.

Question 20

Absolute Rated Filter

Answer 20

Bx>=75
Beta Ratio, eff, and dirt holding capacity determinded by conducting a multipass test.
All absolute filter elements are depth type filtration.

Question 21

Nominal Rated Filter:

Answer 21

No industry standard exists to determine nominal element ratings.
Suface filtration (nominal) applied in actual systems can not achieve dirt holding capacities derived through multipass testing.