Chapter Ten - Definitions

Question 1

What are alkaline cleaners?

Answer 1

Cleaners that saponification most oils and greases, and their surface-active components wash away other contaminants. These cleaners may also saponify certain coating vehicles.

Question 2

What is ceramic grit?

Answer 2

Relatively expensive abrasives that are justified by their special properties. Their particles retain sharp cutting edge, and are especially effective on hard-base materials which may resist effective blasting by chilled cast iron grit.

Question 3

What is crushed slag?

Answer 3

Relatively cheap abrasives that are formed from metallurgical process or combustion. Copper-, nickel-, coal-, and aluminum-slag are common.

Question 4

What are detergents ?

Answer 4

Cleaners that are composed or buffering salts, dispersants, soaps, and inhibitors. They function by wetting, emulsifying, dispersing, and solubilizing the contaminants, which can be washed away using water(usually hot) or steam.

Question 5

What is dry grit blasting( air blasting)?

Answer 5

Blasting that uses a highly concentrated stream of grit projected at a surface to remove rust, mill scale, or other contaminants, creating a rough surface that is good for adhesion.

Question 6

What is emulsion cleaner?

Answer 6

Cleaners that are sprayed onto the surface where they function by wetting, emulsifying dispersing and solubilizing the contaminants

Question 7

What is faying surfaces?

Answer 7

It is surfaces joined to create a friction grip

Question 8

What are gouges?

Answer 8

They are sharp indentations in the coating

Question 9

What are inclusions?

Answer 9

They are a non-metallic phases, such as oxide, sulfide, or silicate particles in a metal.

Question 10

What are organic solvents?

Answer 10

Solvents such as kerosine turpentine naphtha, mineral spirits, toluol, xylol, etc. that clean the metal by dissolving and diluting the oil and grease contamination on the surface.

Question 11

What is pre-cleaning?

Answer 11

It is checking of the surfaces for contamination before surface preparation begins. pre-cleaning involves removing all visible oil, grease, soil, drawing and cutting compounds, and other soluble contaminants from the surfaces.

Question 12

What is surface lamination?

Answer 12

It is the most common surface defects on steel substrates. it is typically caused by rolling the steel.

Question 13

What is surface profile (anchor pattern)?

Answer 13

The irregular peak in valley profile on a bare surface that can result from operations such as abrasive blast cleaning or power tool cleaning.

Question 14

What is a Venturi nozzle?

Answer 14

This blasting nozzle permits abrasive velocity up to 720 km/h ( 450mph), or 660 ft./s with an almost equal impact or the entire surface. Venturi nozzle are the most effective shape for tough cleaning jobs

Question 15

What is waterblasting?

Answer 15

Use of pressurized water discharged from the nozzle to remove unwanted material from a surface.

Question 16

What is water jetting?

Answer 16

Use of standard jetting water discharged from the nozzle at pressures of 70 MPa (10,000 psig)or greater to prepare a surface for coating.

Question 17

What is Weld spatter?

Answer 17

Particles of molten metal produced during welding and thrown into the surface adjacent to the weld.

Question 18

What are acidic cleaners?

Answer 18

Cleaners that remove soil by chemical attack, they dissolve the reaction products. They are usually composed of fairly strong acids, such as phosphoric acid(H3PO4), with small quantities of surfactants, water-miscible solvents, and organic wetting and emulsifying agents.