Virina Steel:
Advancing Grinding Technology

Virina Steel LLC is a pioneering manufacturer of high-performance
grinding balls for the cement and mining industries. Leveraging a
proprietary nanotechnology steel formula, protected by a US patent
filed in 2013 with additional claims filed in 2025.

Virina grinding balls are the best in the world—period. If you’re not completely satisfied after one year, we’ll give you a 100% refund.

• Per SGS ASTM 14, it is the finest grain size grinding ball
• Per SGS, the only grinding ball has a through-hardness of 63 HRC from
surface to core
• Purchase only one Fresh Charge
• Annual top-off 3% of the original Fresh Charge weight
• Annual wear rate 2mm per ball
• No Spitzers to remove
• No annual sort
• Reduce downtime by 5%
• Extend liner lifespan by 400%
• Annual energy savings per mill up to 25%
• Increase cement production per mill up to 15%

In grinding balls, through-hardness refers to the consistency of hardness throughout the entire ball, from the surface to the core.

This is in contrast to surface-hardened balls, which have a hard outer layer and a softer interior.

Benefits of through-hardness in grinding balls:

Consistent wear and reduced breakage: Through-hardened balls wear down more evenly and are less prone to chipping or breakage, especially under high-impact conditions. This contributes to longer service life and reduced operational costs.
Improved grinding efficiency: A uniformly hard ball can better withstand the stresses and impacts of the grinding process, leading to more consistent and efficient material reduction.
Lower risk of contamination: Through-hardened balls are less likely to deform or break, which minimizes the introduction of unwanted material into the grinding process. This is particularly important in applications where purity is crucial, such as pharmaceuticals or food processing.
Enhanced durability: Through-hardening results in a more robust and durable grinding ball that can withstand demanding applications.

In summary, through-hardness is crucial for ensuring optimal performance, durability, and cost-effectiveness of grinding balls in various industrial applications.

In steel, fine grain size generally leads to increased strength, ductility, and toughness, while coarse grain size results in better machinability and hardenability. Fine-grained steel has more grain boundaries, which hinders dislocation movement and thus enhances strength and toughness. Coarse- grained steel, with fewer grain boundaries, is more ductile and easier to
machine.

Elaboration:

Fine Grain Size:

Smaller grains mean more grain boundaries per unit volume. These
boundaries act as obstacles to the movement of dislocations, which are line defects in the crystal structure that are responsible for plastic deformation. This increased resistance to the dislocation movement leads to:

Higher Strength: Fine-grained steel can withstand higher

loads before it starts to deform permanently.
Enhanced Toughness: Fine grains also increase a material's
ability to absorb energy during impact or fracture, making it less
prone to brittle failure.

Coarse Grain Size:

Larger grains mean fewer grain boundaries. This results in:

Lower Strength: Fewer obstacles mean dislocations can move
more easily, reducing the strength of the material.

Higher Ductility: The increased freedom of dislocation

movement can lead to higher ductility, making coarse-grained
steel easier to deform plastically.

ASTM 14 is the finest we report. Attached is what we observed at 500x. I also attached a copy of the chart at 100x magnification. Your grain size was much finer.
Mike Fec
Industrial Services
Technical Manager
Sr. Metallurgical Engineer, SGS MSi

In ball mills, grinding media shape is a crucial factor influencing efficiency and outcomes.

Spherical balls are generally preferred and considered the most efficient grinding media shape. They facilitate better rolling and cascading action, ensuring even and efficient grinding.

However, over time, initially spherical balls can wear and deform into non-spherical fragments. This change in shape can impact grinding performance.

Here's a comparison:

Important Considerations:

Mill conditions and material type play a significant role in determining the ideal grinding media shape and size.
Maintaining a proper balance of media shapes in the mill is essential for consistent grinding performance. Worn balls, which affect efficiency and will increase power consumption, should be removed at regular intervals.
Deformed or broken balls (scats) result from uneven wear and can
negatively affect mill throughput.
Scats are non-spherical and less effective grinding media, taking up valuable space and potentially causing further wear.
Removing scats can significantly improve throughput, as
demonstrated by a case where throughput increased by over 10% after removing 30t of scats.
SAG mills aren't designed to filter out deformed balls specifically, addressing the issue of scats is a crucial aspect of optimizing mill performance and overall circuit efficiency

Wear over time through
abrasion and impact, but
maintain their shape
better for longer periods.

Feature Spherical Balls Deformed/Worn Balls

Grinding
Action

Efficient rolling and
cascading action
promotes effective
grinding.

Movement differs significantly,
potentially leading to less efficient
grinding zones. They have surface
and linear contact interactions,
while spherical balls have point
contact.

Efficiency

Particle Size

Wear

Typically considered the most efficient grinding media shape, leading to faster size reduction and lower energy consumption.

Can reduce grinding efficiency,
increasing power consumption.

Efficient in producing finer particle sizes.

May result in coarser products.

More susceptible to self-wear and breakage.

Below is the SGS test of a Virina cut half ball, core at 63 HRC

Engineered Solutions for Superior Grinding Performance

MIDWEST CEMENT PLANT WITH TWIN MILLS INSTALL TWO NEW LINERS
HEAD-TO-HEAD COMPARISON OF WEAR RATE AND LINER LIFE

VIRINA vs TRADITIONAL BALLS

The plant has two identical, 4500 hp – 2 compartments, 100 TPH ball mill circuits grinding

Type II Portland cement.

Both mills have recent shell and division headwear liner replacements and are in similar operating condition.
Both mills have identical 88-ton 1st chamber ball charges and ball size distribution.
One mill received a fresh ball charge with Virina balls, and the other with Traditional balls.
Nanotechnology mill shell temperature at 184 F
Virina balls provide greater grinding efficiency due to their round surface in the shearing and tumbling layer.
Higher efficiency with lower energy consumption.
Traditional ball mill shell temperature at 195 F, 11 Degrees higher.
Traditional balls are made of lower-quality steel.
Traditional balls waste energy ball on ball deformation.
Deformed balls strike the liner above the toe, damaging the shelf.
Deformed balls slide on the liner, causing ball runs.
Deformed balls cause poor material flow.
Deformed balls decrease production.
Deformed balls decrease the lifespan of the liner.

Midwest Cement Plant

The plant has two identical 4,500 hp, two-compartment, 100 TPH ball mill circuits
for grinding.

Both mills have identical 88-ton ball charges in the first chamber.

After five years, Virina balls show no need for sorting, as shown in the
accompanying image.

No noticeable deformation after five years; surface and core remain at 63 HRC.

The balls’ annual wear rate is 2 mm.Ball wear progression: 90 mm to 80 mm, 80 mm
to 70 mm, 70 mm to 60 mm.

VS ball in silver and copper SAG MILL no deformation 2.jpg

HIGH COST TO CONSTANTLY REPLACING DEFORMED TRADITIONAL BALLS

After two annual grinding campaigns, a significant percentage of Traditional balls are deformed, leading to decreased production and increased energy consumption.
Sorting stops production and requires labor costs.
After five years, Virina’s 90 mm balls wear to 80 mm.
Virina balls have a grinding life of up to 40 years, 20 times that of Traditional balls.

Spherical balls have much higher grinding efficiency than deformed balls.

The value of Virina balls can be 30 times that of Traditional balls.

Traditional balls begin deforming after only four months.

Plants continue grinding with deformed balls due to the high cost of replacement.
A traditional 90 mm ball can deform to 93 mm by 88 mm in four months.
Grinding efficiency deteriorates, and deformation accelerates after the outer layer wears off, exposing the softer inner core.
Grinding with deformed balls reduces production, wastes energy, and damages the liner.

VIRINA & BRAND X LOADED IN JANUARY 2018
TEMPERATURE MEASUREMENT IN JANUARY 2024

The plant has two identical, 4500 hp – 2 compartments, 100 TPH ball mill circuits grinding Type II Portland cement.
Both mills have recent shell and division headwear liner replacements and are in similar operating condition.
Both mills have identical 88ton ball charges and ball size distribution.
Both mills received a fresh ball charge, one with Virina balls and other Brand X balls.
Virina Mill Shell temperature at 184 F.

Greater grinding with the round surface at the Shearing and Tumbling Layer

Higher efficiency with lower energy consumption.

Brand X Mill Shell temperature at 195 F 11 Degrees higher.
Deform ball at a time will strike the liner above the toe and damage the shelf
Deform ball has a higher percentage of rolling off the shelf without crushing the material.
Deform ball at time will slide on the liner and hit other deformed balls.

The presence of damage shelfs in the ball mill circuits can have a significant impact on the lifespan of the liner. This is a critical factor to consider, as it directly affects the operational efficiency and maintenance costs of the mill.

VIRINA’S MILL IS 11 DEGREES COOLER THAN THE TRADITIONAL BALL MILL, RESULTING IN 400
MBTU ANNUAL ENERGY SAVINGS.

VIRINA’S BALLS WILL NOT DEFORM
PROJECTED TO EXTEND THE LINER LIFE BY 4X

Spherical balls follow a predictable parabolic
trajectory into the cataracting and impact
zone, maximizing crushing and grinding
efficiency.
Round balls roll over one another, grinding
material in the shearing and tumbling zone.
Round balls save up to $125,000 annually in
energy costs.
Deformed balls have an unpredictable
trajectory and damage the liner’s shelf.
Deformed balls slide on the liner, causing
wear and ball runs.
The useful life of the shell liner depends on
maintaining the liner surface profile and
lifter shelf.
Most mills replace liners after using only a
fraction of their weight due to profile wear.
Round balls may extend liner lifespan by up
to 400%.

ASTM 14 is the finest we report.

Your grain size was much finer.

Attached is ASTM 10 illustration
we don’t have ASTM 14 illustration.

Mike Fec

SGS MS

iIndustrial Services

Sr. Metallurgical Engineer

Virina ASTM 14 has 128,000
grains per square mm
Traditional ball ASTM 8 has
2,048 grains per square mm
Virina grain size is 62X finer
than traditional.
Ultra-fine grain size has a larger
surface-area-to-volume ratio;
the more grain boundaries, the
stronger and tougher the
grinding ball. A coarse-grain ball
will wear much faster than a
fine-grain ball.

Mike Fec
Industrial Services
Technical Manager
Sr. Metallurgical Engineer
SGS Lab
1390 N 25th Avenue
Melrose Park, IL 60160

In an attempt to cut the ball, the
SGS mechanical lab tried their
abrasive saw with no luck.

They tried 2 separate cut.

The ball was forwarded to the
shop, where there is a more
robust abrasive saw.

That was the 3rd cut.

Virina balls, with fine grain and consistent 63 HRC hardness from surface to core, do not deform.

No sorting is required until after 10 years, when 70 mm balls wear to 50 mm and are then loaded into the second chamber.
No mill stoppage is needed except for annual inspections and adding a 3% top-off. No debris to remove or rejects to dispose of.
Sorting and handling the ball charge takes days, requires up to five workers, and at least one bobcat loader.
Sorting many 55-gallon drums of balls, a few at a time, is time-consuming.
The average cement plant earns a profit of up to $50 per ton. This is an avoidable cost.

PER SGS

Virina is the only
grinding ball that has surface
to the core at 63 HRC
Virina’s through hardness with a
spherical shape will grind evenly
and will never deform.
A 90mm ball with 2mm annual wear
rate will grind for 45 years

Deformed grinding balls lead to problems in the cement grinding process.

Deformed grinding balls lead to

problems in the cement grinding
process.

Inefficient grinding, increased wear

and tear on the mill liner, uneven

particle size distribution for

equipment damage.

Reduced grinding capacity and higher

operational costs due to the need for

more frequent ball replacement.

All stemming from the irregular

contact and impact forces caused by
the deformed balls within the mill

Decarbonization

Producing each ton of balls generates 1.9 tons of CO2 emissions (World Steel Association).

The average cement plant discards 25 tons of Traditional balls per mill annually, generating 46 tons of CO2 emissions.

Virina’s mill operates at 184°F, while the Traditional ball mill operates at 195°F.

Higher temperatures in Traditional mills result from ball runs, deformed balls hitting the liner wall and shelf, and further deforming the balls. This temperature difference equates to 400 MBTU, generating 39 tons of CO2 emissions annually.

Traditional balls contribute 46 tons (discarding) and 39 tons (operation), totaling 85 tons of CO2 emissions annually.

Virina’s annual wear is 3 tons, generating 5 tons of CO2 emissions.

Traditional balls increase CO2 emissions by 85% compared to Virina balls due to casting and
operational inefficiencies.

Virina balls further reduce CO2 emissions by: