plaquette MACHLINE - Ntn-snr.com

Dimensions by series
Bore
719 70 72
Comparison of cross-sections
for a given same bore
72 70 719
Bearing series
and version codes
Series
Version code
7000 V
71900 V
7200 G1
Comparison of cross-sections
for a given outside diameter
- V version: Series 71900 and 7000 are the best suited
to high rotation speeds. They provide the best
combination of speed, capacity, rigidity and precision
characteristics.
- G1 version: The G1 version was specially designed
to meet series 7200 specifications, which is designed
to withstand predominantly major axial loads.
Outside diameter
Features
of versions on offer
- UNIVERSAL bearing, code U: with the selected
preload, the inner ring and outer ring surfaces of
these bearings are on the same plane. All types of
arrangements can be achieved with this bearing.
- Arrangements of UNIVERSAL bearings, codes DU,
TU, QU...: Arrangement of several universal bearings
whose outside diameters and bores are selected to
ensure a tolerance range no more than half the ISO
tolerance level.
- Arrangements of MATCHED bearings, codes DB,
DF, DT, Q16, Q21...: These assemblies are matched
by SNR and must not be re-arranged. They have
the following characteristics:
- Matching preload values,
- Variation of outside diameter and bore values
within a tolerance range no more than half the ISO
standard tolerance,
- Assembly is identified with a “V” marked on the
outside diameter of all bearings in an assembly.
These features, in particular the extremely precise
preload values, mean that greater spindle precision
can be achieved, with better rigidity and longer life.
Version selection:
SNR offers several options for creating
a bearing arrangement.
Examples of identification codes for matched assemblies
DB DF DT Q16 Q21
= Direction of maximum machining load applied to shaft
Specific tolerances
Certain specific applications may require bearings
with lower bore and outside diameter tolerances,
values centered with respect to ISO 4 tolerance
specifications. These bearings are identified with the
letter R, as shown in the following coding example:
71912CVURJ74.
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