FAQ: Precision Miniature Balls /
Bearings, Stainless Steel Bearing Balls

Q: What gives chrome balls better
performance properties than plain
carbon steel?

A: Chrome balls contain greater percentages of key alloying metals,
including chromium, silicon and manganese. Chromium contributes
toughness, and helps resist wear, corrosion and discoloration;
silicon and manganese both increase strength

Q: Where are precision
miniature balls used?

Precision Miniature Balls

A: Precision miniature balls are those under 1/8 inch (3 mm) in diameter.
Precision miniature balls are commonly used in medical, dental and
optical instruments, miniature bearings, ball screws and pumps.
Material options include chrome steel, stainless steel,
tungsten carbide, plastic and glass.

Q: What are the best options for
stainless steel bearing balls?

A: Our page on stainless steel bearing balls can help you decide.

Q: What are some good criteria for
deciding whether a ball or roller is best
for a given rolling motion application?

A: There are 6 main factors to consider – here’s how balls and rollers
compare on that basis:

Precision Miniature Balls

Hartford has some excellent tools to help you through the process and
make the best decision for your application. Email us

Q. What are the main differences between
300 and 400 series stainless steel balls?

A: 300 series “austenitic” stainless steel balls contain chromium and
nickel and are non-magnetic. They have better corrosion resistance than
400 series, (in fact, the highest corrosion resistance of the stainless group).
They are less brittle, and can be hardened by cold working.

A 400 series “martensitic” stainless steel ball is “straight chromium.”
It contains more carbon to make it magnetic, and offers less corrosion
protection than 300 series. It can be readily heat treated to increase
hardness, making it more brittle. Martensitic grades are specified for
applications that demand strength, hardness and wear resistance.

Q. What standards does Hartford
adhere to for ball manufacturing?

A: Hartford products conform to these major standard industrial
specifications for precision balls:

ANSI / AFBMA Standard 10 Metal Balls
ISO 3290 Rolling Bearings – Balls – Dimensions and Tolerances
DIN 5401 Finished Steel Balls for Rolling Bearings
ASTM F 2215
ASTM F2215
ASTM F2215-08
ASTM F 2215-08

Q. What about MIL spec balls?

A: Yes – see our MIL spec balls page.

Q. Do you supply balls for valves?

A: Yes – see our balls for valves page, or our hollow steel balls page.

For more on miniature balls,
see www.hartfordtechnologies.com/miniature-balls.htm

Visit here for a quick overview of stainless steel ball facts.

Hartford Technologies is a leading b2b American manufacturer of custom ball & roller bearings and bearing assemblies,
precision miniature balls, and precision rollers, pins, and shafts with manufacturing facilities in the U.S. and China.
We provide comprehensive value-added services, including application engineering and inventory management,
to a customer base that spans automotive to medical, leisure products to agriculture.

Hartford customers include leading OEMs, and diverse, specialized manufacturers on four continents. Our commitment
is to combine technical innovation with agility, responsiveness and institutional strength - strength that comes from a
conservative management team, global manufacturing and logistics capability, and more than 80 years of leadership.

FAQ: Precision Miniature Balls / Bearings, Stainless Steel Bearing Balls

Q: What gives chrome balls better performance properties than plain carbon steel?

Q: Where are precision miniature balls used?

Q: What are the best options for stainless steel bearing balls?

Q: What are some good criteria for deciding whether a ball or roller is best for a given rolling motion application?

Q. What are the main differences between 300 and 400 series stainless steel balls?

Q. What standards does Hartford adhere to for ball manufacturing?