Union Process is the source for the most up-to-date information on grinding balls and other media. Click the link at left to download a detailed sheet, outlining factors to consider when selecting grinding media, along with specifications on the most common types of media. |
How To Select Your Grinding Balls and Other Grinding Media
Union Process, Inc., innovator and custom-manufacturer
of the ATTRITOR and DELTAMILL, meets all your grinding and
dispersing requirements with a full line of the highest quality
grinding media, including carbon steel, stainless steel and
chrome steel grinding balls. Selection of grinding media depends
upon several factors, some of which are interrelated:
* Initial feed size-Smaller media cannot easily break up large particles.
* Final particle size-Smaller media are more efficient when ultrafine particles
are desired.
* Specific gravity-In general, high-density media give better results.
The media should be more dense than the material to be ground. Also, highly
viscous materials require media with a higher density to prevent floating.
* Hardness-The harder the media, the better the grinding efficiency and,
consequently, the longer the wear.
* pH-Some strong acid or basic slurries may react with certain metallic
media.
* Discoloration-Certain media result in color development and are, therefore,
not suitable in the production of some materials such as white coatings.
* Contamination-Material resulting from the wear of the media affect the
product and may need to be removed by a magnetic separator, chemicals,
or a sintering process.
* Costs-Media that may be 2-3 times more expensive may last considerably
longer, and therefore, be well worth the extra cost over the long run.
Our skilled technical service representatives are always available for
consultation and ready to assist you with the selection of media that best
answers your particular needs.
GRINDING MEDIA SPECIFICATIONS
Sizes shown in red indicate media that is recommended for use
in small media mills except where stated otherwise.
Metallic
Carbon Steel Grinding Balls (SAE 1013 -- case-hardened, SAE 1065--through-hardened)
Specific Gravity: 7.8
Hardness: ROCKWELL C 60 - 62
Relative Cost: Low
Sizes Available:
1/8". 3/16", 1/4", 5/16". 3/8". 1/2"
Chrome Steel Grinding Balls (SAE 52100)
Specific Gravity: 7.8
Hardness: ROCKWELL C 62 - 66
Relative Cost: Low to Moderate
Sizes Available:
1mm, 1.59mm, 2mm
1/8", 5/32", 3/16", 7/32", 1/4", 5/16", 3/8", 1/2", 2mm, 2.38mm, 3.2mm
Stainless Steel Grinding Balls (AISI 440-C)
Specific Gravity: 7.7
Hardness: ROCKWELL C 55-64
Relative Cost: Moderate
Sizes Available:
1/8", 5/32", 3/16", 7/32", 1/4", 5/16", 3/8", 1/2", 3/4"
Steel Shot, Through-Hardened
Specific Gravity: 7.7
Hardness: ROCKWELL C 55 - 60
Relative Cost: Low
Sizes Available:
.25mm, .40mm, .50mm, .71mm, 1.18mm, 1.40mm, 1.70mm, 2mm
2.36mm, 2.80
Non-Metallic
Alumina
99.9% Balls
Specific Gravity: 3.9
Hardness: Hv 1750 kg/mm2
Relative Cost: Moderate
Sizes Available:
0.2mm, 0.5mm
1mm, 2mm, 3mm, 5mm, 10mm
99.5% Balls
Specific Gravity: 3.4 - 3.7
Hardness: Hv 1350 kg/mm2
Relative Cost: Moderate
Sizes Available:
0.2mm, 0.5mm
1mm, 2mm, 3mm, 5mm, 8mm, 10mm, 15mm, 20mm
99% Satellites
Specific Gravity: 3.4 - 3.7
Hardness: ROCKWELL 45N 78-79
Relative Cost: Moderate
Sizes Available:
3/16", 1/4"
96% Satellites
Specific Gravity: 3.4 - 3.7
Hardness: Hv 1400 kg/mm2
Relative Cost: Low to Moderate
Sizes Available:
1/4", 1/2"
94% Satellites
Specific Gravity: 3.4 - 3.7
Hardness: Hv 1200 kg/mm2
Relative Cost: Low to Moderate
Sizes Available:
1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 8mm, 10mm, 13mm, 15mm, 20mm
90% Satellites
Specific Gravity: 3.4 - 3.7
Hardness: ROCKWELL 45N 75
Relative Cost: Low
Sizes Available:
3mm, 7/32", 1/4", 3/8". 1/2"
Ceramic (Steatite) Satellites
Specific Gravity: 2.6 - 2.7
Hardness: ROCKWELL 45N 60-65
Relative Cost: Low to Moderate
Sizes Available:
1/8", 1/4", 5/16", 3/8", 1/2"
Glass Beads (Lead Free)
Specific Gravity: 2.5
Hardness: KNOOP 515 kg/mm2
Cost: Low
Sizes Available:
0.4 – 0.6mm, 0.5 – 0.75mm, 0.6 – 0.8mm, 0.75 – 1.0mm,0.8 – 1.0mm, 1.0 – 1.2mm, 1.0 – 1.25mm, 1.1 – 1.3mm,
1.2 – 1.4mm, 1.25– 1.55mm, 1.4 – 1.6mm, 1.55 – 1.85mm, 1.6 – 1.8mm, 1.7 – 2.0mm, 1.8 – 2.0mm
2.0 – 2.3mm, 2.0 – 2.4mm, 2.3– 2.6mm, 2.3 – 2.7mm, 2.5– 2.85mm, 2.8 – 3.2mm, 2.85– 3.3mm, 3.2 – 3.8mm,
3.3– 3.6mm, 3.6 – 4.1mm, 3.7 – 4.3mm, 4.2 – 4.8mm, 4.7 – 5.3mm, 5.0mm, 5.7 – 6.3mm, 6.0mm,
6.7 – 7.3mm, 7.0mm, 7.6 – 8.4mm, 8.0mm, 8.6 – 9.4mm, 9.0mm, 9.5 – 10.5mm, 10mm, 10.5 – 11.5mm, 12mm, 14mm, 15mm, 16mm
Mullite Beads
Specific Gravity: 2.8
Hardness: ROCKWELL 45N 70
Relative Cost: Low
Sizes Available:
1/8"
Nylon Pellets
Specific Gravity: 0.7 - 1.2
Relative Cost: Low to Moderate
Sizes Available:
1/8"
Silicon Carbide Satellites
Specific Gravity 3.1
Hardness: KNOOP 2800 kg/mm2
Relative cost: Very High
sizes Available:
3/16", 1/4"
Silicon Nitride Balls
Specific Gravity: 3.2
Hardness: Hv 1400 - 1500 kg/mm2
Relative cost: Very High
Sizes Available:
0.5mm, 0.8mm, 1mm
2mm, 3mm, 5mm, 10mm, 15mm, 20mm, 25mm
Tungsten Carbide Satellites
Specific Gravity: 14.4 - 14.8
Hardness: 88 - 89HRA
Relative Cost: Moderate to High
Sizes Available:
3/32", 1/8", 5/32", 3/16", 7/32", 1/4", 9/32", 5/16", 3/8", 7/16", 1/2"
Zirconium Oxide (Y203 Stabilized)
75% - Beads
Specific Gravity: 6.0
Hardness: Hv 1280 kg/mm2
Relative Cost: Moderate
Sizes Available:
0.1–0.2mm, 0.2–0.3mm, 0.3–0.4mm, 0.4–0.6mm, 0.6–0.8mm, 0.8–1.0mm, 1.0–1.25mm, 1.25–1.6mm
Zirconium Oxide, High-Purity (Y203 Stabilized)
95% - Balls
Specific Gravity: 6.0
Hardness: Hv 1280 kg/mm2
Relative Cost: High
Sizes Available:
0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.65mm, 0.8mm, 1mm, 1.25mm, 1.5mm, 1.75mm
2mm, 3mm, 5mm, 6mm, 8mm, 10mm, 20mm, 25mm
93% - Beads
Specific Gravity: 6.0
Hardness: Hv 1280 kg/mm2
Relative Cost: High
Sizes Available:
0.5–0.7mm, 0.7–0.9mm, 0.9–1.1mm, 1.1–1.4mm, 1.3–1.6mm, 1.5–1.9mm
Zirconium Oxide (CeO2 rare earth stabilized) Sizes up to 3/16" are beads, 3/16" or larger are satellites.
Specific Gravity: 6.0
Hardness: Hv 1150 kg/mm2
Relative Cost: Moderate
Sizes Available:
0.4–0.6mm, 0.6–0.8mm, 0.8–1.0mm, 0.7–1.2mm, 1.0–1.2mm, 1.2–1.4mm, 1.4–1.6mm
1.7–2.4mm, 2.4–2.8mm, 2.8–3.3mm, 3/16", 1/4", 5/16". 6mm, 8mm, 10mm, 12.5mm, 16mm, 21mm, 26mm, 31mm
Zirconium Oxide (MgO stabilized) Sizes up to 1/4" are beads, 1/4" or larger are satellites.
Specific Gravity: 5.4
Hardness: Hv 900 - 1000kg/mm2
Relative Cost: Moderate
Sizes Available:
0.6–0.85mm, 0.85–1.18mm, 1.18–1.4mm, 1.4–1.7mm, 1,7–2.3mm
1/4", 3/8", 1.2", 3/4"
Zirconium Sillcate Beads
Specific Gravity: 3.85
Hardness: MOHS 7.0
Relative Cost: Moderate
Sizes Available:
0.1–0.2mm, 0.2–0.3mm, 0.3–0.4mm, 0.4–0.6mm, 0.6–0.8mm, 0.8–1.0mm, 1.0–1.25mm, 1.25mm. 1,25–1.6mm, 1.6–2.0mm
2.0–2.5mm, 2.5–2.8mm, 2.5–3.15mm
NOTE: Grinding balls and media are sold on a per pound basis,
but ATTRITORS and DELTAMILLS are loaded by volume. Therefore,
the more dense the media, the more pounds of media required.
For instance, a machine requiring only 40 lbs. of stainless
steel may require up to 80 lbs. of tungsten carbide. Information
contained herein is accurate and reliable to the best of our
knowledge, but our suggestions and recommendations cannot
be guaranteed because the conditions of use are beyond our
control.
For
more information, contact Media Sales.
Phone: (330) 929-3333 x228
Fax: (330) 929-3034
E-mail: mediasales@unionprocess.com
