Ball Rollers : Characteristics

NBK Ball Rollers Transport Heavy Objects Swiftly

We have achieved smooth ball rotations by surrounding the main ball with multiple sub-ball. A small friction coefficient allows for transporting workpieces with minimal force. With rotations smooth in any 360° direction, changing transport directions is easy.

Starting coefficient of friction

A heavy object (SS400 and surface polished) was loaded onto three ball rollers. The force that made the object start moving was measured by a push gauge to calculate the starting coefficient of friction μ.

Upward Type

Part Number Starting coefficient of friction μμ
BRU*S-S
(Main unit / Main ball: Stainless Steel)
0.03
BRU*S-N
(Main unit: Stainless Steel / Main ball:
Polyacetal)
0.04
BRU*N-N
(Main unit / Main ball: Polyacetal)
0.08
BRU*P-P
(Main unit / Main ball: PEEK)
0.08

Plunger Type

Part Number Starting coefficient of friction μμ
BRPSS-S
(Main unit / Main ball: Stainless Steel)
0.15
BRPSS-N
(Main unit: Stainless Steel / Main ball:
Polyacetal)
0.1
BRPPS-S
(Main unit / Main ball: Stainless Steel)
0.03
BRPIN-N
(Main unit / Main ball: Polyacetal)
0.15
BRPMS-S
(Main unit / Main ball: Stainless Steel)
0.03

Downward Type

Part Number Starting coefficient of friction μ
BRD*
(Main unit / Main ball: Steel)
0.03

● Numerical values in the tables are test measured values, but not
guaranteed values.

Abundant Lineup

Upward Type

A standard ball roller type. The lineup includes various types such as set screws, hexagon head bolts, and round head bolts. Also featured in the lineup are not only all-stainless steel types with excellent corrosion resistance, but also resin ball types which do not damage the workpiece and PEEK types suitable for clean environments. Types whose main unit is made of resin come with a drain hole. They are suitable for such applications as food manufacturing lines that require cleaning. Wide variations from M5 to M20. Available for everything from miniature workpieces through transport of heavy objects.

Types whose main unit is made of stainless steel cannot be used downward or sideways due to their sub-ball arrangements. Types whose main unit is made of resin can be used both downward and sideways.

Plunger Type

Ball rollers with plunger function. 
The internal spring enables an unbalanced load, if any, to be equally received by the roller. Can also be used as a general ball plunger for workpiece fixing / positioning etc. Smooth ball rotation reduces wear on the main ball and recipient.

About loads for plunger types

Initial load (min.) Load when main ball begins to sink
Maximum load (max.) Load when main ball has sunk to its lowest limit.

Downward Type

Ball rollers that can be used downward or sideways. The built-in strike plate makes the main ball and sub-ball come in proper contact in whatever direction they are used. Dust-proof seal prevents dirt or dust infiltration inside. Main unit, main ball and sub-ball are made of steel. They have excellent durability. Recommended applications include casters for carrying trolleys.

Response to Special Needs

We manufacture ball rollers according to customized dimensions, shapes, materials, surface treatment, cleanroom wash and special specifications. Please contact our Customer Service.
Please feel free to contact our customer service.

Customer Service

  • Usage Method
  • Technical Question
  • Customization Products

NBK America LLC

8:00 to 17:00 on weekdays, Eastern Standard Time