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Introduction of Performance by Use
2 Machine Tools

High-Load Life Test Using Cutting Coolant which is Contaminated with Cast Iron Particles

3 Samples of different lubricant conditions

Test conditions

Sample: LY45BN (Preload Z4)

Load: 9 800 N per one ball slide

Preload: 4 400 N Grease: AV2

Feed: Average 24 m/min Stroke: 400 mm

Contamination: Coolant dilution 30:1

FCD45 particles 115 MESH (125 μm or less) added at 5% (by

weight)

Pattern: 2 days in coolant (ball grooves of rail are immersed) 5 days no

coolant

Friction force change Test results

150 No.1 No.2 No.3 Sample Lubricating Condition Lost Result
condition (*1) Broken end cap Flaking Preload Distance (km)
100 Running year (*2)

50 End cap broke

0Friction force, N No.1 Grease Yes No Yes prematurely
0 only Test due to inadequate
Lubricant volume, cm3 stopped way of lubrication and
particles.

600 km, 0.8 years.

NSK K1 Running uninterrupted
No.2 (4 pcs.) No
No No over 3 600 km,
+ Grease
5 years.

Shortened life

No.3 Oil only No Slight Yes because of particle
and inadequate way of
500 1 000 1 500 2 000 2 500 3 000 3 500 4 000 lubrication. 3 000 km,

Running distance, km 4.1 years.

(*1): No replenishment of grease to sample No.1 and No.2 during test.

(*2): Running year is calculated by 720 km/year (average 3 m/min × 16 hr/day ×

250 days/year).

Merit Comparison of lubricant consumption
Estimated oil consumption in the test equivalent to 5 years
• Reduced expense for lubricants (see graph in the right) running (for 4 LA45 slides)

• No oil or grease supply systems required 40 000
 Reduced equipment cost
35 000 0.45 cm3 × 16 hr/day
• Improved machine design time and efficiency 30 000 × 250 days/year × 5 years
 No piping design required × 4 slides 36 000 cm3

• Better for the environment 25 000
 NSK K1 reduces lubricant consumption, minimizes waste
oil

20 000

15 000

10 000

5 000

3