ABRASIVE BLASTING - vsrd international journals division

VSRD International Journal of Mechanical, Civil, Automobile and Production Engineering, Vol. 3 No. 7July 2013 / 261 

e-ISSN : 2249-8303, p-ISSN : 2319-2208 © VSRD International Journals : www.vsrdjournals.com 

REVIEW ARTICLE 

ABRASIVE BLASTING 

1Satish W. Karadbhuje* and 2 Anup S. Raghuwanshi 

1Lecturer, Department of Mechanical Engineering, 

2Lecturer, Department of Electronics & Telecommunication Engineering 

1,2 

Sai Polytechnic, Kinhi (Jawade), Maharashtra, INDIA. 

*Corresponding Author : swkaradbhuje@yahoo.com 

ABSTRACT 

Abrasive blasting is the operation of forcibly propelling a stream of abrasive material against a surface under high pressure to smooth 

a rough surface, roughen a smooth surface, shape a surface, or remove surface contaminants. A pressurized fluid, typically air, or 

a centrifugal wheel is used to propel the blasting material (often called the media). The first abrasive blasting process 

was patented by Benjamin Chew Tilghman on 18 October 1870. There are several variants of the process, such as bead blasting, 

sandblasting, soda blasting, and shot blasting. 

Keywords : Abrasive Material, Blasting Material, Bead Blasting, Shot Blasting. 

1. INTRODUCTION 

Abrasive blasting of steel substrates can provide the best 

possible surface preparation for coatings adhesion. If done 

properly, abrasive blasting thoroughly cleans the surface 

and creates a surface profile for mechanical adhesion. To 

achieve the economy available through abrasive blasting, 

the operator must maintain the productivity and efficiency 

of the cleaning system through careful attention to all of its 

components. The principle of air-supported abrasive 

blasting is very elementary. Compressed air propels 

abrasive particles at high velocities to impact and clean a 

substrate. All the equipment between the air compressor 

and the emission of abrasive particles is used to supply, 

convey, and accelerate the abrasive. Three basic 

components are found in most abrasive blasting operations: 

The equipment, the abrasive, and the personnel. Careful 

attention to these three basic components is the key to the 

success or failure of the entire operation. 

2. WET ABRASIVE BLASTING 

Common features include: the ability to use extremely fine 

or coarse media with densities ranging from plastic to steel, 

the ability to use hot water and soap to allow simultaneous 

degreasing and blasting, elimination of dust—so silicacious 

materials can be used without worry, hazardous material or 

waste can be removed without danger—e.g., removal 

of asbestos, radioactive, or other poisonous products from 

components and structures leading to effective 

decontamination. 

The process is available in all conventional formats 

including hand cabinets, walk-in booths, automated 

production machinery and total loss portable blasting units. 

Process speeds can be as fast as conventional dry sand 

blasting when using the equivalent size and type of media. 

However the presence of water between the media and the 

substrate being processed creates a lubricating cushion that 

can protect both the media and the surface from excess 

damage. This has the dual advantage of lowering media 

breakdown rates and preventing impregnation of foreign 

materials into the surface. Hence surfaces after wet blasting 

are extremely clean, there is no embedded secondary 

contamination from the media or from previous blasting 

processes, and there is no static cling of dust to the blasted 

surface. Subsequent coating or bonding operations are 

always better after wet blasting than dry blasting because of 

the cleanliness levels achieved. The lack of surface 

recontamination also allows the use of single equipment for 

multiple blasting operations—e.g., stainless steel and 

carbon (mild) steel items cannot be processed in the same 

equipment with the same media without problems. 

3. BEADBLASTING 

Bead blasting is the process of removing surface deposits 

by applying fine glass beads at a high pressure without 

damaging the surface. It is used to clean calcium deposits 

from pool tiles or any other surfaces, and removes 

embedded fungus and brighten grout color. It is also used 

in auto body work to remove paint. 

4. WHEEL BLASTING 

In wheel blasting, a wheel uses centrifugal force to propel 

the abrasive against an object. It is typically categorized as 

an airless blasting operation because there is no propellant 

(gas or liquid) used. A wheel machine is a high-power, 

high-efficiency blasting operation with recyclable abrasive 

(typically steel or stainless steel shot, cut wire, grit, or 

similarly sized pellets). A specialized wheel blast machine 

propels plastic abrasive in a cryogenic chamber, and is 

usually used for deflashing plastic and rubber components. 

The size of the wheel blast machine, and the number and

Satish W. Karadbhuje and Anup S. Raghuwanshi VSRDIJMCAPE, Vol. III (VII), July 2013 / 262 

power of the wheels vary considerably depending on the 

parts to be blasted as well as on the expected result and 

efficiency. The first blast wheel was patented by 

Wheelabrator in 1932. 

5. HYDRO-BLASTING 

Hydro-blasting, commonly known as water blasting, is 

commonly used because it usually requires only one 

operator. In hydro-blasting, a highly pressured stream of 

water is used to remove old paint, chemicals, or buildup 

without damaging the original surface. This method is ideal 

for cleaning internal and external surfaces because the 

operator is generally able to send the stream of water into 

places that are difficult to reach using other methods. 

Another benefit of hydro-blasting is the ability to recapture 

and reuse the water, reducing waste and mitigating 

environmental impact. 

6. MICRO-ABRASIVE BLASTING 

Main Article: Abrasive Jet Machining :: Micro-abrasive 

blasting is dry abrasive blasting process that uses small 

nozzles (typically 0.25 mm to 1.5 mm diameter) to deliver a 

fine stream of abrasive accurately to a small part or a small 

area on a larger part. Generally the area to be blasted is 

from about 1 mm 2 to only a few cm 2 at most. Also known 

as pencil blasting, the fine jet of abrasive is accurate enough 

to write directly on glass and delicate enough to cut a 

pattern in an eggshell. The abrasive media particle sizes 

range from 10 micrometers up to about 150 micrometers. 

Higher pressures are often required. 

9. BRISTLE BLASTING 

Main Article: Bristle Blasting : Bristle blasting, unlike 

other blasting methods, does not require a separate blast 

media. The surface is treated by a brush-like rotary 

tool made of dynamically tuned high-carbon steel wire 

bristles. Repeated contact with the sharp, rotating bristle 

tips results in localized impact, rebound, and crater 

formation, which simultaneously cleans and coarsens the 

surface. 

10. EQUIPMENT 

Portable Blast Equipment : Mobile dry abrasive blast 

systems are typically powered by a diesel air compressor. 

The air compressor provides a large volume of high 

pressure air to a single or multiple "blast pots". Blast pots 

are pressurized, tank-like containers, filled with abrasive 

material, used to allow an adjustable amount of blasting grit 

into the main blasting line. The number of blast pots is 

dictated by the volume of air the compressor can provide. 

Fully equipped blast systems are often found mounted 

on semi-tractor trailers, offering high mobility and easy 

transport from site to site. Others are hopper-fed types 

making them lightweight and more mobile. 

In wet blasting, the abrasive is introduced into a pressurized 

stream of water or other liquid, creating slurry. Wet blasting 

is often used in applications where the minimal dust 

generation is desired. Portable applications may or may not 

recycle the abrasive. 

The most common micro-abrasive blasting systems are 

commercial bench-mounted units consisting of a power 

supply and mixer, exhaust hood, nozzle, and gas supply. 

The nozzle can be hand-held or fixture mounted for 

automatic operation. Either the nozzle or part can be moved 

in automatic operation. 

7. AUTOMATED BLASTING 

Automated blasting is simply the automation of the abrasive 

blasting process. Automated blasting is frequently just a 

step in a larger automated procedure, usually involving 

other surface treatments such as preparation and coating 

applications. Care is often needed to isolate the blasting 

chamber from mechanical components that may be subject 

to dust fouling. 

Fig. : Device Used For Adding Sand to the Compressed 

Air 

Blast Cabinet 

8. DRY ICE BLASTING 

In this type of blasting air and dry ice are used and with the 

help of a huge mass and air pressure the parent material is 

cleaned without destroying the properties of the parent 

material. 

Fig. : A Sand-Blasting Cabinet


A blast cabinet is essentially a closed loop system that 

allows the operator to blast the part and recycle the 

abrasive. It usually consists of four components; the 

containment (cabinet), the abrasive blasting system, the 

abrasive recycling system and the dust collection. The 

operator blasts the parts from the outside of the cabinet by 

placing his arms in gloves attached to glove holes on the 

cabinet, viewing the part through a view window, turning 

the blast on and off using a foot pedal or treadle. Automated 

blast cabinets are also used to process large quantities of the 

same component and may incorporate multiple blast 

nozzles and a part conveyance system. 

There are three systems typically used in a blast cabinet. 

Two, siphon and pressure, are dry and one is wet: 

A siphon blast system (suction blast system) uses the 

compressed air to create vacuum in a chamber (known 

as the blast gun). The negative pressure pulls abrasive 

into the blast gun where the compressed air directs the 

abrasive through a blast nozzle. The abrasive mixture 

travels through a nozzle that directs the particles 

toward the surface or workpiece. 

Nozzles come in a variety of shapes, sizes, and 

materials. Tungsten carbide is the liner material most 

often used for mineral abrasives. Silicon carbide and 

boron carbide nozzles are more wear resistant and are 

often used with harder abrasives such as aluminum 

oxide. Inexpensive abrasive blasting systems and 

smaller cabinets use ceramic nozzles. 

In a pressure blast system, the abrasive is stored in the 

pressure vessel then sealed. The vessel is pressurized to 

the same pressure as the blast hose attached to the 

bottom of the pressure vessel. The abrasive is metered 

into the blast hose and conveyed by the compressed gas 

through the blast nozzle. 

Wet blast cabinets use a system that injects the 

abrasive/liquid slurry into a compressed gas stream. 

Wet blasting is typically used when the heat produced 

by friction in dry blasting would damage the part. 

BlastRoom : A blast room is a larger version of a blast 

cabinet and the blast operator works inside the room. A 

blast room includes three of the four components of a blast 

cabinet: the containment structure, the abrasive blasting 

system and the dust collector. Most blast rooms have 

recycling systems ranging from manual sweeping and 

shoveling the abrasive back into the blast pot to full reclaim 

floors that convey the abrasive pneumatically or 

mechanically to a device that cleans the abrasive prior to 

recycling. 

Media : In the early 1900s, it was assumed that sharp-edged 

grains provided the best performance, but this was later 

demonstrated not to be correct. 

Mineral : Silica sand can be used as a type of mineral 

abrasive. It tends to break up quickly, creating large 

quantities of dust, exposing the operator to the potential 

development of silicosis, a debilitating lung disease. To 

counter this hazard, silica sand for blasting is often coated 

with resins to control the dust. Using silica as an abrasive is 

not allowed in Germany, United Kingdom, Sweden, 

or Belgium for this reason. 

Another common mineral abrasive is garnet. Garnet is more 

expensive than silica sand, but if used correctly, will offer 

equivalent production rates while producing less dust and 

no safety hazards from ingesting the dust. Magnesium 

sulphate, or kieserite, is often used as an alternative 

to baking soda. 

Agricultural : Typically, crushed nut shells or fruit kernels. 

These soft abrasives are used to avoid damaging the 

underlying material such when cleaning brick or stone, 

removing graffiti, or the removal of coatings from 

printed circuit boards being repaired. 

Synthetic : This category includes corn starch, wheat 

starch, sodium bicarbonate, and dry ice. These "soft" 

abrasives are also used to avoid damaging the underlying 

material such when cleaning brick or stone, removing 

graffiti, or the removal of coatings from printed circuit 

boards being repaired. Soda blasting uses baking soda 

(sodium bicarbonate) which is extremely friable, the micro 

fragmentation on impact exploding away surface materials 

without damage to the substrate. 

Additional synthetic abrasives include process byproducts 

(e.g., copper slag, nickel slag, and coalslag), engineered 

abrasives (e.g., aluminum oxide, silicon carbide or 

carborundum, glass beads, ceramic shot/grit), and recycled 

products (e.g., plastic abrasive, glass grit). 

Metallic : Steel shot, steel grit, stainless steel shot, cut wire, 

copper shot, aluminum shot, zinc shot. 

Many coarser media used in sandblasting often result in 

energy being given off as sparks or light on impact. The 

colours and size of the spark or glow varies significantly, 

with heavy bright orange sparks from steel shot blasting, to 

a faint blue glow (often invisible in sunlight or brightly lit 

work areas) from garnet abrasive. 

Safety : Cleaning operations using abrasive blasting can 

present risks for workers' health and safety, specifically in 

portable air blasting or blast room (booth) applications. 

Although many abrasives used in blasting rooms are not 

hazardous in themselves, (steel shot and grit, cast 

iron, aluminum oxide, garnet, plastic abrasive and glass 

bead), other abrasives (silica sand, copper slag, nickel slag, 

and staurolite) have varying degrees of hazard (typically 

free silica or heavy metals). However, in all cases their use 

can present serious danger to operators, such as burns due 

to projections (with skin or eye lesions), falls due to 

walking on round shots scattered on the ground, exposure to 

hazardous dusts, heat exhaustion, creation of 

an explosive atmosphere, and exposure to excessive noise.


Blasting rooms and portable blaster's equipment have been 

adapted to these dangers. Blasting lead-based paint can fill 

the air with lead particles which can be harmful to the 

nervous system. 

The Occupational Safety and Health Administration 

(OSHA) mandates engineered solutions to potential 

hazards, however silica sand continues to be allowed even 

though most commonly used blast helmets are not 

sufficiently effective at protecting the blast operator if 

ambient levels of dust exceed allowable limits. An adequate 

level of respiratory protection for blast operations in the 

United States is approved by the National Institute for 

Occupational Safety and Health (NIOSH). 

Typical safety equipment for operators includes: 

Positive pressure blast hood or helmet – The hood or 

helmet includes a head suspension system to allow the 

device to move with the operator's head, a view 

window with replaceable lens or lens protection and an 

air-feed hose. 

Grade-D air supply (or self-contained oil-less air 

pump) – The air feed hose is typically attached to a 

grade-D pressurized air supply. Grade-D air is 

mandated by OSHA to protect the worker from 

hazardous gases. It includes a pressure regulator, air 

filtration and a carbon monoxide monitor/alarm. An 

alternative method is self-contained, oil-less air pump 

to feed pressurized air to the blast hood/helmet. Oilless 

air pump does not require an air filter or carbon 

monoxide monitor/alarm, because the pressurized air is 

coming from a source that cannot generate carbon 

monoxide. 

Ear protection – ear muffs or ear plugs 

Body protection – Body protection varies by 

application but usually consists of gloves and overalls 

or a leather coat and chaps. Professionals would wear a 

cordura/canvas blast suit (unless blasting with steel 

abrasives, then they would use a leather suit). 

In the past, when sandblasting was performed as an openair 

job, the worker was exposed to risk of injury from the 

flying material and lung damage from inhaling the dust. 

The silica dust produced in the sandblasting process would 

cause silicosis after sustained inhalation of the dust. In 

1918, the first sandblasting enclosure was built, which 

protected the worker with a viewing screen, revolved 

around the workpiece, and used an exhaust fan to draw dust 

away from the worker's face. 

Sandblasting also may present secondary risks, such as falls 

from scaffolding and absorption of lead particles when 

removing lead-based paint from infrastructure. 

Several countries and territories now regulate sandblasting 

such that it may only be performed in a controlled 

environment using ventilation, protective clothing and 

breathing air supply. 

11. WORN-LOOK JEANS 

Many consumers are willing to pay extra for jeans that have 

the appearance of being used. To give the fabrics the right 

worn look sandblasting is used. Sandblasting has the risk of 

causing silicosis to the workers, and in Turkey, more than 

5,000 workers in the textile industry suffer from silicosis, 

and 46 people are known to have died from it. Sweden's 

Fair Trade Center conducted a survey among 17 textile 

companies that showed very few were aware of the dangers 

caused by manually sandblasting jeans. Several companies 

said they would abolish this technique from their own 

production. 

12. APPLICATIONS 

The lettering and engraving on most modern cemetery 

monuments and markers is created by abrasive blasting. 

Sandblasting can also be used to produce three-dimensional 

signage. This type of signage is considered to be a higherend 

product as compared to flat signs. These signs often 

incorporate gold leaf overlay and sometimes crushed glass 

backgrounds which is called smalts. When sandblasting 

wood signage it allows the wood grains to show and 

the growth rings to be raised, and is popular way to give a 

sign a traditional carved look. Sandblasting can also be 

done on clear acrylic glass and glazing as part of a store 

front or interior design. 

Sandblasting can be used to refurbish buildings or create 

works of art (carved or frosted glass). Modern masks and 

resists facilitate this process, producing accurate results. 

Sandblasting techniques are used for cleaning boat hulls, as 

well as brick, stone, and concrete work. Sandblasting is 

used for cleaning industrial as well as commercial 

structures, but is rarely used for non-metallic workpieces. 

13. CONCLUSION 

It is well known that correct surface preparation is essential 

to achieving the full life of any coating or coating system. 

Abrasive blasting is recognized as the most effective means 

of obtaining the correct surface cleanliness and surface 

profile. Careful attention to all the components of an 

abrasive blasting system, including the air supply, the 

abrasive blast equipment, the abrasive, and the expertise of 

the operator, can assure that any abrasive blasting operation 

obtains its maximum level of efficiency. 

14. REFERENCES 

[1] Smil, Vaclav (2005). Creating the twentieth century: 

technical innovations of 1867–1914 and their lasting impact. 

Oxford University Press US. ISBN 978-0-19-516874-7. 

[2] "BRIDGEPORT PROJECT / SOUTHWEST DIVISION 

HISTORY". Archived from the original on 23 June 2011. 

Retrieved 9 June 2011. 

[3] 1919 Popular Science article on types of minerals found to be 

suitable for sandblasting – Little Grains of Sand, Popular


Science monthly, February 1919, page 64, Scanned by 

Google 

Books:http://books.google.com/books?id=7igDAAAAMBAJ 

&pg=PA64 

[4] "OSHA Asked to Ban Silica in Abrasive Blasting". Paint 

Square. 11 May 2009. Retrieved 9 June 2011. 

[5] "Abrasive Blasting". NIOSH Topics. NIOSH. Retrieved 10 

July 2012. 

[6] Making Things Easier for the Sand-Blaster, Popular Science 

monthly, December 1918, page 76, Scanned by Google 

Books:http://books.google.com/books?id=EikDAAAAMBAJ 

&pg=PA76 

[7] Buer, Kathleen (11 December 2010). "Dettedør folk for" 

[People are dying for this]. TV 2 Norway (in Norwegian). 

Retrieved 11 December 2010. 

Bibliography: 

[8] Manufacturing Processes Reference Guide by Robert H. 

Todd, Dell K. Allen, and Leo Alting—1st ed. 

[9] Tool and Manufacturing Engineers Handbook, Vol1 : 

Machining, 4th Edition, 1983. Society of Manufacturing 

Engineers. 

•••

Satish W. Karadbhuje and Anup S. Raghuwanshi VSRDIJMCAPE, Vol. III (VII), July 2013 / 266

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