Special Issue; Products for Industrial Machinery - NTN

NTN TECHNICAL REVIEW No.742006
New Product
Ultra-Clean Bearing for Clean Environments
Ryouichi NAKAJIMA
Masaaki HONDA
NTN manufactures Ultra-Clean bearings for clean
environments used for a semiconductor and LCD panel
fabrication equipments, vacuum evaporation systems, etc.
NTN developed Ultra-Clean NC bearings and Ultra-Clean
WB bearings to supply the demand for a long-life under high
temperature and heavy load conditions.
1. Overview
Extremely low dust generation is needed for the
bearings used in the systems and machines that
manufacture semiconductor devices and liquid crystal
display panels, as well as for those used in the
vacuum evaporation systems for these products.
Recently, demand has been mounting for longer
maintenance intervals for these devices and systems.
Given these demands, the bearings used in these
situations must be capable of durable operation in
high-temperature and high-load environments. To
address these engineering challenges, NTN has
developed a unique lubrication system, and with this,
they have successfully developed unique Ultra-Clean
NC bearings that feature long life in vacuums under
high bearing pressure and unique Ultra-Clean WB
bearings that boast long life in high-temperature
environments. This report introduces these unique
bearings.
Conventional oil-impregnated resin cages are made
of sintered resin materials, and, consequently, their
porosity, the ratio of pores to retain lubricating oil, was
20% at maximum. In contrast, NTN’s newly developed
Fig. 1 Ultra-Clean NC bearing
NCNetwork Cell
2. Introduction to NTN Ultra-Clean NC
Bearings (Fig. 1)
For lubrication, the authors adopted a porous resin
cage that was developed independently by NTN. This
cage is impregnated with a low-vapor-pressure oil
(Fig. 2).
Fig. 2 Porous resin cage
400
Pore
Industrial Engineering Dept. Industrial Sales headquarters
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