CHAPTER 23 131

CHAPTER 23
REVISION QUESTIONS REVISION QUESTIONS
CORROSION
SURFACE PREPARATION
(Answer of question from course notes) (Answer of question from course note)

01- Direct Current ( DC ) 01- BS 410.

02- Anodes 02- BS 410.
03- Anodes, Cathodes and Electrolyte. 03- COSHH REGULATION.
04- A substance which will conduct a current and be broken down by its. 04- Cross section of Blasting Profile.
05- Degradation of metal by a Chemical or Electrochemical means. 05- To remove contamination for better adhesion between a paint and the substrate.
06- From Cathodes to Anodes. 06- Lamination or crack, appear to be a longitudinal crack, which one lip curling back.
07- Hydrogen gases. 07- A small surface lamination which stand upright like a needle after blasting.
08- Steel. 08- Surface Preparation, Key, Peak to through height.
09- Aluminum. 09- As a permanent records.
10- Steel. 10- Degree of cleanliness.
11- Iron Sulphate and Iron Chlorides. 11- Dependant on the time spent on the area and velocity of the particles.
12- Zinc, Alloy and Magnesium. 12- Cannot, surface comparator used for assess degree of roughness only.
13- 25 - 100µm. 13- 40 - 115µm.
14- Zinc will corrode. 14- 20 - 50µm.
15- Galvanic Series, Electrochemical Series, Electromotive Force Series. 15- Molecular Attraction and Molecular Interference.
16- Marine’s environment. 16- Molecular Attraction – negatively charge particle attracted to positively areas and vise versa (
17- Wustite, Magnetite and Hematite. analogy magnet )
18- Magnesium. Molecular Interference – Because the surface is rough and uneven the paint wets and lock into
19- Industrial and agriculture. the profile (analogy Velcro/physical).
20- Causes by Hygroscopic Salts. 17- 25.4µm.
21- Positively or negatively charge atom. 18- Blast profile, anchor pattern and amplitude.
22- Current either positive or negative ( DC + or DC - ) 19- 450 mph.
23- Positive Charge 20- Moisture.
24- Cannot, because three factors needed for corrosion to occur, anodes, cathodes and electrolyte. 21- 20% - 30% Grit to 70% - 80% Shoot.
25- Proton, Electron and Neutron. 22- Create more uniform profile which Grit cut a profile and a Shot will control peak to through
26- Blue layer on the surface of substrate causes by combination of oxides compress together in height.
high temperature during rolling process of steel with approximate thickness 25 - 100µm. 23- Steel Shot.
27- Temperature, Hygroscopic Salts, Aerobic Condition, Bacteria, acid and alkalis. 24- Surface Profile Needle Gauge, Dial Micrometer and Replica Tape and Surface Comparator.
28- Because the nobility between steel and mill scale, mill scale more noble than steel and mill 25- Blast to long time at a same area.
scale is easily flack off if temperature applied and will lack of adhesion due to different 26- Factory and confine space.
expansion. 27- Refer to the Engineer for His/Her discretion.
29- Because of three elements for corrosion was there. 28- Fine, Medium and Course.
30- Because there is no protection at the steel. 29- Finer than Fine and Coarser than Coarse.
30- Garnet size 3060.

132

SURFACE PREPARATION
40- 65 till 70°C.
(Answer of question from course note) 41- After Pickling Process complete, immerse the steel substrate into a bath of
phosphoric/Chromic acid, 2 % solution at 80°C for approximately one to two minute with iron
01- Preparation of steel substrate before application of paints and related product. filling (0.5%) and after that rinse in clean water and check for Ph values. Value should be at
02- Size of particles, hardness, density and shape of particle. the range of 4.5 till 7pH.
03- Remove or reduce electric static shock. 42- 20 000psi
04- Hypodermic Needle Gauge. 43- Lot of slurry, use large amount of water and use inhibitor.
05- Long production run, Can control quality, more safety, efficient use of abrasive. 44- After Pickling Process complete, immerse the steel substrate into a bath of
06- Impossible. phosphoric/Chromic acid, 2 % solution at 80°C for approximately one to two minute with iron
07- Yes, the appearance. filling (0.5%) and after that rinse in clean water and check for Ph values. Value should be at
08- No different. the range of 4.5 till 7pH.
09- Yes, Rust grade D have a heavy pitted. 45- Reduce dust and good to remove toxic paint.
10- 220mph. 46- To forms rust inhibitive layers, which passivate the surface and increase the adhesion
11- 100psi per nozzle. properties and also extremely resistant to cathodic disbondment.
12- Polishing and smooth shiny areas which does not provide good adhesion. 47- Treated by abrading with emery clothes.
13- SA 1 48- No.
14- 7pH 49- 14 photos, 2 for rust grade A, 4 photos for each rust grade B, C and D.
15- Using pH indication strip paper. 50- Grit Blasting.
16- To retards the formation of corrosion product.
17- Rust Grade A and D.
18- Pickling process followed by passivation process.
19- 0 till 7pH.
20- 7 till 14pH
21- Litmus paper to measure of either acid or alkalis.
22- Supply a large amount of water, disposal of slurry and mix of inhibitor.
23- Revert, screw, bolt and nuts.
24- Expansion, Dehydration and Heat penetration.
25- AF1, BF1, CF1 and DF1.
26- Needle Jetting or Needle Gun.
27- Standard of tooling- ST 2 means thorough hand and power tool cleaning and ST 3 means Very
thorough hand and power tool cleaning.
28- Phosphorus Bronze and Beryllium Bronze.
29- Burnishing did not provide a good adhesion of paint.
30- Leave a very coarse profile and need to repair by abraded with emery clothes.
31- 4.5 Till 7pH.
32- Oil or water filter/separator.
33- 80% production.
34- Xylene
35- Blasting Triggers which always under operator control.
36- To reduce or remove electric shock of static.
37- By Air Wash Separator.
38- Very hazardous to the operator.
39- High pressure water blasting up to 30000psi, High pressure water plus abrasive injection, Low
pressure water plus abrasive injection and Water Blasting.

133
 133 & 134 30- Carbon and aluminium.
135
PAINT TECHNOLOGY (1)

01- Powder paint.

02- Ketones / Acetone.
03- High resistance to mould growth, non-flammable, resistance to chemical attack, non toxic and PAINT TECHNOLOGY (2)
easy maintenance.
04- Low resistance to some solvent, low temperature tolerance (65°C maximum) and spray
application resulted in ‘cobwebs ‘. 01- Poly means many and Mers means single units, can be single atom or molecule.
05- White Spirits. 02- Joining together of a string structure of repeated units.
06- Chlorine. 03- Linear polymer, branched polymer and cross linked polymer.
07- No, CR contain with strong solvent and Alkyd contain with weak solvent, if CR applied over 04- Less than 45% oil to resin.
Alkyd its will result a lifting. 05- More than 60% oil to resin.
08- Aliphatic Hydrocarbon/White spirits. 06- Inert particle with excellent scattering properties in order to give covering power, opacity and
09- From words of Alcohol and Acid reaction. colour.
10- Inert particles with excellent light scattering properties in order to give covering power, 07- 1/10th micron.
opacity and colour. 08- Saturated oil will not solidify by polymerisation to form a film and unsaturated oil will
11- A Binder. combine with oxygen.
12- Acceptable, weak solvent binder over strong solvent binder not creates any paint fault. I.e. 09- Semi drying oil and Non drying oil.
lifting. 10- Dye can easily dissolve but pigment cannot.
13- Not acceptable, strong solvent binder over weak solvent binder will spoilt the paint system. 11- Animal, vegetable, mineral and synthetically produce.
I.e. lifting. 12- White colour.
14- Acceptable, weak solvent binder over strong solvent binder not creates any paint fault. I.e. 13- Red Lead, calcium plumbhate, Coal tar and zinc chromate.
lifting. 14- Kaolin, china clay, calcium plumbhate, magnesium silicate and aluminium silicate.
15- Not acceptable, strong solvent binder over weak solvent binder will spoilt the paint system. 15- Micacous iron oxide, Glass flake, Graphite and Aluminium flake.
I.e. lifting. 16- A film have a good gloss properties but poor covering power and have tendency to blister or
low cohesive strength.
16- Acceptable, weak solvent binder over strong solvent binder not creates any paint fault. I.e. 17- Critical Pigment Volume Concentration.
lifting. 18- For a shelf life of paint.
17- Not acceptable, strong solvent binder over weak solvent binder will spoilt the paint system. 19- A black colour.
I.e. lifting. 20- Ease of application, adhesion to substrate, abrasion resistance, chemical resistance and
18- Dye and varnish. cohesive strength.
19- Very brittle and fast dry. 21- Added into primer to protect the steel substrate by by passivation.
20- Must be a type that will combine with oxygen (unsaturated). 22- ??????????
21- Forms thick impermeable layer of high electrical resistance. 23- All particle are not wetted, the paint film would be porous, low in cohesive strength and
22- Causing a chemical reaction between the paint constituent and the substrate. adhesion.
23- By sacrifical coating. 24- Zinc phosphate.
24- Multi Component Liquids paints. 25- Provide adhesion, cohesion, films strength and durability.
25- For ease application, adhesion to substrate, abrasion resistance, chemical resistance, cohesive 26- Green, yellow and oranges.
strength and ability to resist the passage of water. 27- T o give paint flexibility and reduce brittleness.
26- Copal, dammar and coumarone. 28- Zinc and Aluminium.
27- Linseed oil, castor oil, olive oil, tung oil, Soya oil and palm oil. 29- For oxidizing oil and resin which are added during paint manufacturing.
28- A mixture of oil and resins. 30- A jelly paint, non drip and if stir would be change into normal liquid.
29- Silicones, usually carbon or aluminium pigmented.

136 & 137

136 & 137 71- The temperature at which water vapor in the air will condense.
31- Process of milling or grinding a paint ingredient to a suitable size. 72- The amount of water vapor in the air expressed as a percentage of the amount of water vapor
32- Its will retard the formation of skin on the paint surface. which could be in the air at that same temperature.
33- Alkyd resins and non drying oil. 73- Always wet bulb first and immediately.
34- The resulting liquids I.e. salts mix with water will result salty water. 74- At a speed of 4meter/second.
35- Salt mix into water will result salty water, sugar mix into water will result sweeten water. 75- Distilled water.
36- Paint consist of solid particles suspended in the vehicle where is no solubility. 76- Aspirated Hygrometer and Psychrometer.
37- Suspension and Emulsion. 77- Decrease.
38- Convertible/Non Reversible. 78- Must be according to BS 2482.
39- Cross linked Polymer. 79- Limpet Gauge, Digital Thermometer, Thermocouple and Touch Pyrometer.
40- Chlorinated Rubber, Vinyl, Acrylic, cellulous material and lacquer. 80- Impossible.
41- Allowing the polymer in a paint structure back into solution.
42- Not allowing the polymer in a paint structure back into solution.
43- Solvent Evaporation, Oxidation, Chemical Curing and Coalescence.
44- Chlorinated Rubber, Vinyl’s, Acrylic and fall into Linear Polymer categories.
45- The Hegman Grind Gauge which used to measure degree of dispersion of paint.
46- Alkyd, Phenolic and neutral oil and resin.
47- Cross linking Polymer.
48- Reversible or non convertible and linear polymer.
49- Physically joint together.
50- The periods of time after mixing which paint must be used.
51- Amides, Amines and Isocycnate.
52- ????????
53- Giving off heat, the container will warm up.
54- The length of time after mixing which the paint should stand before used.
55- Thermosetting means the material will cure with the application of heat. And Thermoplastic
means materials soften with the application of heat.
56- Cross Linking Polymer.
57- Stand Time and Lead Time.
58- Yes, the time depends on Paint Manufacturer recommendation.
59- Vinyl, Chlorinated Rubber, Alkyd and Cellulose.
60- Thermosetting, the powder will cure with the application of heat.
61- It’s a Barrier coat.
62- ?????????
63- Endothermic reaction, taking in heat, the paint container will cold and forming condensation.
64- Stoving, using oven or infra red.
65- Depends on Technical Data Sheet recommendation from paint manufacture.
66- Heavy metal salts, Octoates or naphtanes of cobalt, manganese and zirconium.
67- To keep solid particulated constituents in depression within the paints.
68- Alkyd and Non drying oil.
69- ?????
70- By oxidizing.

136 & 137

 31- Testing a pain in a situation of tropical condition.
32- Higher than density of water.
PAINT TESTING 33- Solvent would reduce or change the volume solids percentage in paint.
34- 100cc capacity.
35- Specific Gravity used for water and Density used for solvent.
36- Water absorption.
01- Fluids resistance to flow, where the liquids with a high viscosity is one which a high 37- Subject to constant cycle temperature from hot to cold and hot again.
resistance to flow and it would not run easily, a low viscosity is fluids runs very easily. 38- Constant expansion and contraction which can result in a crack.
02- Liquids with a high resistance to flow. And would not run easily. 39- Ballotini Test and BK Drying Time Recorder.
03- One centi poise. 40- When there are no any scratches visible on a paint surface.
04- CGS-Poise and SI-Newton per square meter. 41- Black and white fused plate, Through Type and Hiding Power Chart and micrometer
05- Ford Flow Cup, Zhan and Frikmar and DIN. adjustable film applicator.
06- Time in second at the measure temperature (second/20°C±0.5) 42- Capability of paint to giving hiding power to the underlying surface.
07- Diameter of nozzle opening at the bottom of cup. 43- To checked opacity of paint.
08- Dynamic Viscosity and Kinematics Viscosity. 44- To determine the individual thickness of paint film.
09- Comparing the sample taken from the operator at the point of application and the sample from 45- To control thickness during application which give a confidence that after paint dry the
the paint manufacture technical data sheet. thickness still in the range of dry film thickness a per spec requirement and control a paint
10- Ford Flow Cup. consumption.
11- Temperature would effect the drying and curing of paint under test. 46- Eccentrics Rims and Wet Combs.
12- Rotothinner giving dynamic viscosity and Krebs Stomer giving kinematics viscosity. 47- To determine accurate thickness reading.
13- Clean and dry the cup, put on the triangular stand and make it parallel using spirit bubble 48- Comparing with paint manufacturer technical data sheet.
leveling on the lid of cup, open a cup, place a finger at a nozzle under a cup, fill a cup with a 49- No, used for ferrous metal substrate only.
paint under test and clean out any accesses if paint by ruler, standby with stop watch, at the 50- No, used for non ferrous metal substrate only.
time we remove our finger from nozzle immediately at the same time press start button at stop 51- No, used for ferrous metal substrate only.
watch and look at the first brake of paint which drop from nozzle under cup and stop the stop 52- Hiding power chart in opacity test.
watch. The reading should be Second/20°C±0.5. 53- Glossmeter.
14- The Hegman Grind Gauge. 54- By a reflectance of light at specified angle.
15- NO, the higher temperature is better and safer. 55- Degree of dispersion, particle size, resin type, solvent type and pigment volume concentration.
16- (page 68) 56- 40µm.
17- (page 65) 57- 10-20µm.
18- Able Cup. 58- Almost 100%.
19- Blue flame flash over the cup. 59- Degree of gloss for primer and mid coat paint.
20- Weight per Volume. (W÷V) 60- Light would be deflected and the gloss percentage reading would be lower.
21- Density of X ÷ Density of water. 61- V-Cut test, Cross Hatch Cut and Dolly test.
22- Density of Water. 62- Dolly Test units in Mpa/psi/lb/Newton.
23- Relative Density Cup, Specific Gravity Cup, Weight per liter Cup, Weight per gallon Cup and 63- Cohesive failure within a paint film.
Pyknometer. 64- Sodium Chlorides.
24- Kinematics Viscosity. 65- Hydrogen and Chlorine gas.
25- Taber Rotary Abraser. 66- After V-Cut the paint must not exposed the substrate. I.e. F.B.E 5mm only after 28 day.
26- Conical Mandrels. 67- Sacrificial Anodes and Impress Current.
27- Tubular Impact Tester. 68- ??????????
28- Test the hardness of paint after fully cured. 69- ??????????
29- Determine correct mixing ratio and correct percentage of thinner added into a paint. 70- No, these systems only control the corrosion formation.
30- Humidity Cabinet, Salt Spray Cabinet, Water Soak Test, Temperature Cycling and prohesion
test. 138 & 139
138/139

71- Yes, by primary defence ( coating)

72- No, at the liquids level only by cathodic protection, the rest, by paint.
73- Setting at 9volts.
74- Setting at 67.5volts or 90volts.
75- Detergent or washing liquids.
76- To allow immediate penetration of the water and providing a very low resistance circuit back
to the control box.
77- No advice.
78- To wet out the entire surface.
79- Direct Current.
80- High voltage Holiday Detector.