Dear readers, in this blog post we will go over just a few facts regarding cast steel shot and grit, and cut wire shots.

Steel Shot and Grit – Due to production process microstructure contain internal defects such as: cracks, voids, shrinkage etc.

Defect can be present in a volume up to 10% by mass. Due to internal microstructure defects particles experience premature failure (breakdowns).

Cut Wire ShotDue to production process, microstructure does not contain any internal defects. No particle premature failure.

Density:

SS & Grit – Due to internal microstructure defect density of steel shot and grit is cca. 7 kg/dm3.

CW Shot – Density of cut wire shots is 7,86 kg/dm3

Grain size consistency:

SS & Grit – Cast steel shot and grit doesn’t have uniform particle size distribution within new product.

For example:

Shot S390 contain particles of 0,85mm, 0,9mm, 1,0mm, 1,2mm in size.

Grit G16 contains particles of 1mm, 1,2mm, 1,4mm, 1,6mm in size.

Proportion of grain size distribution isn’t uniform among product packages or transportation packages.

Due to non-uniform particle size distribution, difficult to maintain stable operating mix.

Operational mix should be checked on regular basis.

CW Shot – Cut wire uniform grain size particle distribution within new product comparing to all other types of blast cleaning media.

For example:

Cut wire shot of 1,4mm in size; contain only particles with 1,4mm in size. Due to uniform particle size distribution easy to maintain stable operation mix. Operational mix doesn’t need to be checked on regular basis.

Operation mix:

SS & Grit – Operation mix is the most important property of blast cleaning efficiency.

Not stable.

Due to uneven wear rate and particle breakdowns during operation, very difficult to maintain stable operation mix.

Blast cleaning efficiency varies.

Surface roughness profile varies.

Surface coverage varies.

Increased consumption of subsequently applied coatings.

CW Shot – Stable operation mix.

Constant and maximum blast cleaning efficiency during all the time of blast cleaning operations.

No variation in blast cleaning efficiency.

No variation in surface roughness profile.

No variation in surface coverage.

Decreased consumption, up to 30%, of subsequently applied coatings.

In the next blog posts regarding cut wire shots in general, we will go over more facts and case studies and help you decide what is best for your surface treatment.

For further information, feel free to contact us via e-mail, phone, social media or through our website chat.

Best regards,

SPAJIC doo team