What Is Blast Cleaning?
Blast Cleaning is the operation of forcibly propelling a stream of abrasive material against a surface under high pressure. Pressurised liquids, air, or a centrifugal wheel are generally used as the propellant. In previous years it was often referred to as Sandblasting or Media Blasting, it is an excellent process used to clean building facades.
There are several different media used for the process, such as Dry Ice, Grit, Water and Soda blasting. The choice of technique will be dictated by:
- the nature of the substrate or material to be blasted or cleaned
- the nature of the surface contamination
- any environmental considerations
- the cost and speed of application
Uses of blast cleaning
In summary, blast cleaning can be used to:
- smooth a rough surface
- roughen a smooth surface
- shape a surface
- remove surface contaminants
Why blast cleaning is a highly skilled task
The two main variants of blast cleaning refer to the type of particle that is “blasted” and the pressure at which this is done.
- Pressure: Blast cleaning is a specialist commercial cleaning task because the pressure used has to be adjusted to ensure that only the desired layers of material are removed. If the surface that is to be cleaned or treated is not uniform, the pressure may also need to be adjusted as the work is carried out.
- Particle size and type: grit, water, co2 etc. Each media used has cleaning up implications following application, some more serious than others.
Materials used in blast cleaning
- Grit is the most traditional substrate used for blast cleaning. Standard grit is suitable for cleaning heavily corroded steel, marine growth and cement build-up. It is also used as a base treatment before metal particles are employed.
Finer grits will give a more efficient clean in terms of time and amount of substrate required and would typically be used on surfaces with a special finish such as stainless steel or aluminium.
Coarser grits, containing more stone particles, are used to remove thick layers of grime and oil from stone surfaces to create an authentic aged effect on older stone once cleaned.
- Calcium Carbonate is normally used either to strip paint from aluminium surfaces or (at low pressure) to remove grime from delicate surfaces such as fabric or wood, including interior beams. This is known as soda blasting.
- Dry Ice – Dry ice is becoming an increasingly popular choice because it evaporates upon contact with the surface and is therefore less disruptive to the environment. It also releases no harmful contaminants into the environment, and generally it can be used more readily in built up areas or in a densely populated area . It produces a sudden cooling effect on the surface which can, for example, be used to separate a coat of resin from metal.
Dry Ice Blasting eliminates the need for disassembly and relocation, solvents, hand-scrubbing, equipment damage and drying time.
- Specialist Materials – There are also some more unusual substances that can be used for particular processes to decarbonise or harden surfaces, or to make them non-slip.
Blast Cleaning applications
Rainbow International are highly experienced in the delivery of blast cleaning for:
- Graffiti removal
- Stone & masonry cleaning
- Soot removal following fire (both internal and external)
- Cleaning building façades
- Cleaning driveways, car parks & public areas
- Rainbow has a wide portfolio of blast cleaning techniques available for all types of applications. The local Rainbow branch will be able to advise the most suitable in any given situation
Rainbow International’s business provides a network of more than 70 multi-personnel, multi-vehicle franchises. Its specialist cleaning services, like blast cleaning, are available to both domestic and commercial clients. It is used by the UK’s top insurance companies and all major loss adjusters as well as many commercial organisations.