CW 01 With Answers

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BGas Painting Inspection Grade 2&3 CW 01

Two examples of Hygroscopic salts would be: (a)

Iron Phosphates and Iron Chromates

(b)

Iron Chlorates and Iron Oxides

(c)

Iron Sulphates and Iron Chlorides

(d)

Iron Sulphides and Iron Silicates

What is an electrolyte? (a)

It is a mixture of salts and water

(b)

A substance which will conduct electricity and cause rusting

(c)

Oxidising liquid which will attack steel

(d)

A substance which will conduct a current and be broken down by it

Corrosion is defined as: (a)

Rusting of the Cathode by electrophysical means

(b)

Oxidation of a metal in contact with water

(c)

Degradation of a material by chemical or electrochemical means

(d)

Breakdown of the metal by hydrogen

Hydrogen is evolved at: (a)

The Anode at all times

(b)

The Cathode at all times

(c)

The Cathode as a by-product of the corrosion reaction

(d)

The Anode as corrosion takes place

The “degradation of material by chemical or electrochemical means” is: (a)

Pickling followed by passivation

(b)

Acid cleaning

(c)

Corrosion

(d)

An Electrolyte

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BGas Painting Inspection Grade 2&3 CW 01

The BGas specification for site application of paint systems is (a)

BGC/PS/PA10

(b)

BGC/PS/CW5

(c)

BGC/PS/PA8

(d)

BS 7079

Another name for the Galvanic List, is: (a)

The Corrosion List

(b)

Electro Negative List

(c)

Electrical Corrosive Properties Series

(d)

Electromotive Forces Series

In the corrosion circuit, electrons travel from: (a)

Anode to cathode

(b)

Cathode to Anode

(c)

Electrolyte to both cathode & anode

(d)

None of the above

If Zinc and Aluminium were in close contact, in the presence of electrolyte: (a)

Aluminium would corrode

(b)

They would corrode equally

(c)

Zinc would corrode

(d)

None of the above

When the electrolyte is water, what occurs at the cathode during a corrosion reaction? (a)

Rusting of the surface would begin

(b)

Oxygen is given off

(c)

Electrons are entering the material

(d)

Hydrogen is evolved

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BGas Painting Inspection Grade 2&3 CW 01

MEM’s are also known as: (a)

Moisture Enriched Materials

(b)

Metal Eating Microbes

(c)

Maximum Evolved Moistures

(d)

Material Electron Mobility

When checking surface profile using X-Course replica tape: (a)

50 micron must be added to the final reading

(b)

The average number of readings must be taken

(c)

50 microns must be deducted from the reading

(d)

A minimum of ten readings must be taken

Which of the following is not a sub atomic particle? (a)

Proton

(b)

Neutron

(c)

Micron

(d)

Electron

Three factors which can affect the rate of corrosion are: (a)

Temperature, Time, and Coating system

(b)

Bi-metallic contact, Hygroscopic Salts, and Bacteria

(c)

Coating system, Pipe diameter, and Ultra Violet light

(d)

Blasting Grades, Rust Grades, and Surface Profile

How many Abrasive Blast Cleaning photographs are in BS 7079 part A? (a)

4

(b)

14

(c)

8

(d)

16

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BGas Painting Inspection Grade 2&3 CW 01

The thickness of Millscale is approximately: (a)

25 μm to 100 μm

(b)

100 to 150 μm

(c)

zero

(d)

Dependant upon the material thickness

The three compressed oxides which form Millscale are: (a)

Iron oxide, Rust, and Iron sulphate

(b)

Wustite, Haematite, and Magnetite

(c)

Iron Sulphate, Iron Chloride, and Iron Phosphate

(d)

RSC, RSJ, and RSA

When preparing stainless steel, what abrasive should be used? (a)

Copper Slag

(b)

Steel Shot

(c)

Aluminium Oxide

(d)

Angular Chilled Iron

A Banana gauge works on which principle (a)

Magnetic resistance

(b)

Conductive resistance

(c)

Tension reluctance

(d)

Viscosity relativity

Rust Grade A can be described as (a)

Tightly adhering Millscale, with evident heavy pitting

(b)

Clean white metal

(c)

Tightly adhering Millscale, with no apparent corrosion

(d)

Millscale which has begun to flake, or can be scraped away

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BGas Painting Inspection Grade 2&3 CW 01

Which Blasting Grade best describes “Thorough Blast cleaning”? (a)

Sa 2

(b)

Sa 2½

(c)

Sa 3

(d)

Sa 1

The two factors to consider when inspecting a surface preparation: (a)

Degree of cleanliness, and time taken

(b)

Surface Profile, and material condition

(c)

Surface Profile and degree of cleanliness

(d)

Degree of cleanliness, and surface contamination

Abrasive used on site for British Gas projects must be: (a)

Mixed with sand, to reduce cost

(b)

Stored correctly prior to use

(c)

Expendable

(d)

Used up to a maximum of three times only.

Which two materials are commonly used as sacrificial anodes? (a)

Copper and Tungsten

(b)

Aluminium and Graphite

(c)

Zinc and Aluminium

(d)

Lead and Tin

Name a sub atomic particle (a)

Atom

(b)

Micron

(c)

Electron

(d)

Moron

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CW 01 Answers 1. C 2. D 3. C 4. C 5. C 6. A 7. D 8. B 9. C 10. D 11. B 12. C 13. C 14. B 15. B 16. A 17. B 18. C 19. A 20. C 21. A 22. C 23. C 24. C 25. C

BGas Painting Inspection Grade 2&3 CW 01