Steel trading companies and fabricators shot blast their steel plate, sections and pipes to achieve a degree of surface cleanliness that is required before protective coatings are applied or other surface preparation needs.
Automated roller conveyor shot blast systems offer solutions which guarantee a highly-efficient descaling, rust /oxidisation removal and general surface cleaning of all kinds of steel.
Shot blasting is a process for the surface treatment of plate, pipes, beams, tubes and bars.
Due to the design, roller conveyor shot blast systems are ideally suited for this application as it allows fast and highly-effective cleaning and surface preparation and at the same time, provides the surface with a profile to which a coating will adhere well, accommodating a wide- range of commercial to marine offshore standards.
The equipment descales the surface of the steel ready to accept a first-class coating, or further engineering processes.
Equipment design and efficiency are paramount and should include the following as basic design and inclusions;
- Infeed and outfeed vestibules should be long enough to stop abrasive escapement
- The blast chamber itself should be constructed from wear-resistant manganese steel
- The blast chamber requires to be further periphery lined with replaceable tiles again manufactured manganese steel, for durability
- The blast requires to be delivered by a number of highly-efficient blast wheels set at an ideal angle to optimise the blasting coverage of the profile or plate
- The blast wheels require to be driven by highly energy efficient electric motors, that are energy saving to the latest design standards of power efficiency
- The system requires to recycle the abrasive and to include an airwash separation screen that is also highly-efficient in its function of separating out dust, scale and fines out to waste bins
- Only good cleaned abrasive should be recycled back for re use
- Abrasive level control is a vital inclusion, as without information, the efficiency of cleaning, repeatability and uniformity of the steel surface is all but impossible
- A rotational brush and blow off unit, after blasting will complete the process and provides a very clean component that can be either removed from the outfeed conveyor or be handled automatically for further processing
- Dust and contaminated air requires to be always drawn through the shotblast system under negative atmosphere, and passed through a very efficient cartridge-type dust collector/filter unit with a discharge back into the hall as low as 1mg/cu mtr down to 0.5 micron particulates and has an efficiency of upto 99.09%
- By placing the cleaned spent air back into the building, residual and any ambient heat can be retained in the winter months which can contribute to the reduction of heating costs of the internal working environment
Generally, standard equipment concepts allow the processing of components from 1000mm wide, upto 5200mm wide and 600mm high. Other configurations may be offered as bespoke equipment and to accommodate more complexly designed fabrications.
Click here for information on cleanliness standards
Click here for information on surface profile
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Shot Blasting Technical Manager
One thought on “Structural Steel Descaling”
The shot blast is very important, it use the steel sand to remove the rust on steel, then process the paint, the shot blast sandard is Sa2.5 for steel structure