S.A.E. Specifications for Shot and Grit Screenings

The SAE requirement for Steel Shot and Steel Grit specifications, must be that the hardness of 90% of the sample will be within a range of 7 HRC points. Rodeco's Steel Shot and Steel Grit products meet or exceed all of the requirements of SAE terms.

Chemical Analysis

Carbon	.80 - 1.2 %
Manganese S-70 - S-110 S-170 S-230 and Larger - All Grit	.35 - 1.2 % .50 - 1.2 % .60 - 1.2 %
Silicon	.4 % minimum
Sulfur	0.05 % maximum
Phosphorous	0.05 % maximum

Microstructure

The Microstructure of cast steel shot and grit shall be uniform Martensite, tempered to a degree consistent with the hardness range, with fine well distributed carbides, if any.

Hardness

Shot
Ninety percent of random hardness check performed on a representative sample shall fall within the range of 402-558 Knoop hardness number (40-51 HRC)

Grit
Ninety percent of random hardness check performed on a representative sample shall fall within the following ranges:

S hardness range of 402-558 Knoop (40-51 HRC)
M hardness range of 495-650 Knoop (47-56 HRC)
L hardness range 612-754 Knoop (54-61 HRC)
H hardness of 732 Knoop minimum (60 HRC).

The hardness may be determined by any of the various methods applicable to small sections such as Micro Hardness Tester with a Knoop indenter, at loads determined to provide a reliable conversion to Rockwell C.

Density

The density of cast steel shall be not less than 7.3 gm/cc grit and 7 gm/cc for shot.

General Appearance

The cast steel shot shall be as nearly spherical as commercially possible and no more than 20% of the shot particles shall have objectionable defects.

Voids for Shot

No more than 10% of the cast steel shot particles shall contain voids as determined at 10X magnification. A void must be greater than 10% of the area of the abrasive particle to be considered harmful.

Shrinkage

No more than 10% of the cast steel shot particles shall contain shrinkage as determined at 10X magnification. Shrinkage is an internal cavity with irregular dendritic surface, whose area is larger than 40% of the particle area.

Cracks

No more than 15% of cast steel shot and 40% of the cast steel grit particles shall have cracks as determined at 10X magnification. A crack is a linear discontinuity whose length is greater than 3 times its width and radial in direction.

Particle Shape of Shot

When examined at 10X magnification, no more than 5% of the shot particles will have a length that is excess of twice the cross section.

Mechanical Tests

Several designs of shot testing machines are available commercially for application to routine procedures. See SAE J445 for methods of checking uniformity of shipments of shot or grit to determine relative fatigue life and energy transfer of different types of shot or grit.

M hardness - 90% minimum
495-650 KHN (47-56 HRC)
L hardness - 90% minimum
612-754 KHN (54-61 HRC)
H hardness - 90% minimum
732 KHN (60 HRC minimum)

STEEL SHOT

SAE Size No.	SAE SHOT Tolerances	Screen Opening In-mm
S780	All Pass No. 7 Screen 85% Min on No. 10 Screen 97% Min on No. 12 Screen	.1110 - 2.80 .0787 - 2.00 0.661 - 1.70
S660	All Pass No. 8 Screen 85% Min on No. 12 Screen 97% Min on No. 14 Screen	.0937 - 2.36 .0661 - 1.70 .0555 - 1.4
S550	All Pass No. 10 Screen 85% Min. on No. 14 Screen 97% Min. on No. 16 Screen	.0787 - 2.00 .0555 - 1.40 .0469 - 1.18
S460	All Pass No. 10 Screen 5% Max on No. 12 Screen 85% Min on No. 16 Screen 96% Min on No. 18 Screen	.0787 - 2.80 .0661 - 1.70 .0469 - 1.18 .0394 - 1.00
S390	All Pass No. 12 Screen 5% Max on No. 14 Screen 85% Min on No. 18 Screen 96% Min on No. 20 Screen	.0661 - 1.70 .0555 - 1.40 .0394 - 1.00 .0331 - 0.850
S330	All Pass No. 14 Screen 5% Max on No. 16 Screen 85% Min on No. 20 Screen 96% Min on No. 25 Screen	.0555 - 1.40 .0469 - 1.18 .0331 - 0.850 .0278 - 0.710
S280	All Pass No. 16 Screen 5% Max on No. 18 Screen 85% Min on No. 25 Screen 96% Min on No. 30 Screen	.0469 - 1.18 .0394 - 1.00 .0278 - 0.710 .0234 - 0.600
S230	All Pass No. 18 Screen 10% Max on No. 20 Screen 85% Min on No. 30 Screen 97% Min on No. 35 Screen	.0394 - 1.00 .0331 - 0.850 .0234 - 0.600 .0197 - 0.500
S170	All Pass No. 20 Screen 10% Max on No. 25 Screen 85% Min on No. 40 Screen 97% Min on No. 45 Screen	.0331 - 0.850 .0278 - 0.710 .0165 - 0.425 .0139 - 0.355
S110	All Pass No. 30 Screen 10% Max on No. 35 Screen 85% Min on No. 50 Screen 90% Min on No. 80 Screen	.0234 - 0.600 .0197 - 0.500 .0117 - 0.300 .0070 - 0.180
S70	All Pass on No. 40 Screen 10% Max on No. 45 Screen 80% Min on No. 80 Screen 90% Min on No. 120 Screen	.0165 - 0.425 .0139 - 0.355 .0070 - 0.180 .0049 - 0.125

STEEL GRIT

SAE Size No.	SAE SHOT Tolerances	Screen Opening In-mm
G10	All Pass No. 7 Screen 80% Min. on No. 10 Screen 90% Min. on No.12 Screen	.1110 - 2.80 .0787 - 2.00 0.661 - 1.70
G12	All Pass No. 8 Screen 80% Min. on No. 12 Screen 90% Min. on No. 14 Screen	.0937 - 2.36 .0661 - 1.70 .0555 - 1.4
G14	All Pass No. 10 Screen 80% Min. on No. 14 Screen 90% Min. on No. 16 Screen	.0787 - 2.00 .0555 - 1.40 .0469 - 1.18
G16	All Pass No. 12 Screen 75% Min. on No. 16 Screen 85% Min. on No. 18 Screen	.0661 - 1.70 .0469 - 1.18 .0394 - 1.00
G18	All Pass No. 14 Screen 75% Min. on No. 18 Screen 85% Min. on No. 25 Screen	.0555 - 1.40 .0394 - 1.00 .0278 - 0.710
G25	All Pass No. 16 Screen 70% Min. on No. 25 Screen 80% Min. on No. 40 Screen	.0469 - 1.18 .0278 - 0.710 .0165 - 0.425
G40	All Pass No. 18 Screen 70% Min. on No. 40 Screen 80% Min. on No. 50 Screen	.0394 - 1.00 .0165 - 0.425 .0117 - 0.300
G50	All Pass No. 25 Screen 65% Min. on No. 50 Screen 75% Min. on No. 80 Screen	.278 - 0.710 .0117 - 0.300 .0070 - 0.180
G80	All Pass No. 40 Screen 65% Min. on No. 80 Screen 75% Min. on No. 120 Screen	.0165 - 0.425 .0070 - 0.180 .0049 - 0.125
G120	All Pass No. 50 Screen 60% Min. on No. 120 Screen 70% Min. on No. 200 Screen	.0117 - 0.300 .0049 - 0.125 .0029 - 0.075

With a 2 lb. sample, we can test your current material to see if it meets specifications. In some cases
we have been able to offer a 40% improvement in performance and media life. Please contact Rodeco on your requirements.

Steel Shot is packaged in 55 gallon drums (2000lb) and in 50 lb bags.
Steel Grit is purchased in 55 gallon drum and 50 lb bags.
G10,G12,G14, G15 - 1800 lb/drum
G18, G25, G40 - 1700 lb/drum
G50 1600lb/drum
G80 1500lb/drum
G120 1400lb/drum