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Te ch D a t a & Ca lcu la t ion s

Technical data and calculations

• An inspector is required to be able to carry out

simple calculations related to the coatings, like WFT

vs DFT, volumes required for specific jobs,

spreading rates, consumptions, simple cost

calculations, solid content and thinning, etc

• Participants will be given the various formulations for calculation and required data during this course

• They must however know where to find such

information on their own once the course has

finished

Technical Data

• Most of the product data we need for carrying out inspections and for carrying out necessary calculations can be found in the Technical Data Sheets (TDS) and/or in the Material Safety Data Sheets (MSDS).

TDS for inspections & calculations

• Corresponding DFT &

WFT

– Minimum

– Maximum

– Typical

• Physical properties

– Vol% solid

– Flash point

– VOC

• Surface preparation

– On various substrates

• Application

requirements

– Ambient conditions

– Methods

• Application Data

– Mixing ratio – Induction time – Pot life

– Thinner No.

– Airless spray data – Thinning

• Drying times

– At various temperatures

• Typical system

– Nos coats – DFT

• Pack size

MSDS for inspections &

calculations

I m por t an t sect ions:

1 Identification

– Where to contact for more info.

2 Composition

– Hazardous ingredients

3 Hazard identification

– Warnings

4 First-aid measures

– What to do in an emergency

5 Fire-fighting measures

6 Accidental release

– Spillage

7 Handling & storage

8 Personal protection

– What PPE must be used

9 Physical properties

– Colour / Odour – Flash point – Density (Sp.G.) – Lower explosion limit – Solubility

10.Stability

– Reactive?

11.Toxicological

– Danger to humans

12.Ecological

– Environment

13.Disposal

– waste

14.Transport 15.Regulation 16.Other

• Can you calculate how high wet thickness to apply

of a product with 65% solid content that has been diluted 15%, in order to achieve a dry film

thickness of 60 microns, and how much will the

total paint and thinner cost should when applying two such coats on the outside of a cylindrical 8

meter high tank with diameter 12 meter, when the loss is estimated to be 35% and the purchase price

is $8.25 for the paint and $2.90 for the thinner?

• You cannot? By the end of this course you should

be able to (might be included in the final

examination)

Calculations : Paint

Abbreviations

Wet Film calculations

• RATIO:

M e a n in g: Sq.m / lt r * W FT = 1 0 0 0

1 : 1 : 1 0 0 0

Ex a m ple :

WFT x % VS

100

250 x 50 100 Formula for determining the DFT

Formula for determining the WFT

Ex a m ple :

DFT x 100 %

% VS

100 x 100 %

65 %

Formula : WFT =

Ex a m ple :

DFT x (100 % + % thinner)

% VS

100 x (100 % + 20 %)

65 %

Formula for determining the WFT after

Formula for determining the WFT after

Volume of thinner = 0,2 litre

65 1,2

100 % x 100 microns

54 %

Theoretical spreading rate

= 6,5m2/litre

% VS x 10

DFT

65 x 10 100

= m2/litre

Formula:

Spreading rate:

Consumption of paint, no loss (1 of 2)

10 x % VS

Consumption of paint, no loss (1 of 2)

500 x 200

10 x 85

500 x 50

10 x 50

Formula: Area, m2 x DFT

10 x % VS

Consumption of Paint with loss

500 x 200

10 x 85 x 0,6

500 x 50

10 x 50 x 0,6

To be painted: Tank, area of 500 m2 , 40 % loss

40 % loss implies that only 60 % will remain on the surface

The correction factor, Loss factor, will be 0.6

Formula: Area, m2 x DFT

10 x % VS x loss factor