Special Issue; Products for Industrial Machinery - NTN

NTN TECHNICAL REVIEW No.742006
Super High-Speed, Long-Life Double Row Cylindrical Roller Bearing
A precision double row cylindrical roller bearing that boasts the highest speed in the world,
while maintaining high load carrying capacity and high rigidity compared to previous design
Features
¡High-speed
Maximum dmn value of 1.75 million with
air-oil lubrication
(50% improvement over previous NTN design)
Maximum dmn value of 1 million with
grease lubrication
(20% improvement over previous NTN design)
Temperature increase on the outer ring ˚C
30
25
20
15
10
5
New design: HSRT6 type
(PEEK cage)
Previous design:
high-strength brass cage
0
4,000 6,000 8,000 10,000 12,000 14,000 16,000
Bearing speed min 1
Structure
¡Optimized internal structure design with
much improved cage
50 75 100 125 150 175 200
Test conditions
dmn value10 4
[New design: HSRT6 type (PEEK cage)]
[Previous design: high-strength brass cage]
¡Bearing size : NN3020K
10015037 mm
¡Bearing speed : 15,000min -1
dmn=1.9 million
¡As-mounted clearance
: 0m
¡Oil supply rate : 0.02mL/20minVG32
¡Air supply rate : 30NL/min
¡Cooling arrangement on the jacket
: Available
Previous design
New design
Fig. 2 Conventional design and new design (HSRT6 Type)
Lubrication pockets
Fig. 1 Temperature rise test results (air-oil lubrication)
Applications
¡Machine tool main spindles, etc.
Fig. 3 Drawing of the retainer
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