Technical Information
Typical Hardness: Rockwell C (HRc)
GS: 40-51 HRc
GM: 47-56 HRc
GL: 54-61 HRc
GH: >60 HRc
Shape: Angular
Bulk Density: 225-275 lbs/cu.ft.
Specific Density: Shall not be < than 7.3g/cc
Other: <1% non-metallic
Packaging: 55-gallon steel drums
G18-G40: 1700 lbs/drum
G50-G80: 1500 lbs/drum
Specifications: SAE J1993
SAE J444
SSPC-AB3
Sigma Steel Grit is manufactured to the SAE J1993 Specification for chemistry, hardness and other characteristics, the SAE J444 Specification for sizing, and the SSPC-AB3 Specification.
GH STEEL GRIT
This is the highest hardness steel grit at +61 HRc. This grit will remain highly angular in an operating mix. It is ideal for deep descaling and roll etching applications. It will yield high cleaning rates in air blast applications. It is not suited for wheel blast applications unless the wheel blast machine has been specifically designed for GH steel grits.
GL STEEL GRIT
The hardness of GL steel grit (54-61 HRc) is lower than GH but still maintains its angularity throughout the blasting process and does not round up as readily as the GM or GS steel grit. It is the ideal hardness for high efficiency closed ciruit blast rooms and will yield high cleaning rates with good efficiency and product life. GL steel grit will increase the wear rate of wheel blast machines if added to the operating mix.
GM STEEL GRIT
GM hardness is 47-56 HRc and overlaps both the GL hardness of 45-61 and the GS hardness of 40-51 HRc. The lower the Rockwell C hardness, the faster the grit will found up and the surface profile will be less consistent than it would be with a GL hardness grit.
GS STEEL GRIT
This is the softest and least aggressive steel grit hardness with a range of 40-51 HRc. This grit is designed more for wheel blast applications where a more aggressive blasting action is required as opposed to a straight steel shot mix. The lower hardness will not cause as much wear and tear on the wheel blast machines. GS grit will round up the fastest and lose most of its angularity.
Sigma High Carbon Steel Grit
COMMON APPLICATIONS
SURFACE PREPARATION to remove a prior coating and to produce an
etched or angular profile to prepare that surface for the coating process
SURFACE CLEANING of rust, mill scale and other contaminants from the
surface
DESCALING of products manufactured with forging, stamping, hot rolling or
drawing processes
SAND REMOVAL from metal castings, most commonly in a wheel blast
machine and utilizing the lowest hardness steel grit