Page 485 - NORTON cutting-off and grinding wheels - industrial

TECHNICALINFORMATION
485
TECHNICAL INFORMATION
Usage Key
Highly recommended
SURFACE FINISH & GRIT SIZE
SURFACE FINISH GRAIN SIZE
µ in CLA µ m Ra 46 60 80 100 120 150 180 220
42 1,10
32 0,80
26 0,70
21 0,50
16 0,40
14 0,35
11 0,25
8 0,20
7 0,17
6 0,14
5 0,12
4 0,10
3 0,08
2 0,05
MIN FORM
RADIUS
METRIC
Ÿmm) 0,75 0,50 0,40 0,25 0,20 0,18 0,13 0,10
IMP INS ,030 ,020 ,015 ,010 ,008 ,007 ,005 ,004
SURFACE FINISH
The achievable surface finish in any grinding
operation is highly dependent upon the grit size
of the grinding wheel. The following chart shows
the range of surface finishes achievable when
using grinding wheels of different grit sizes on
conventional precision grinding applications,
together with the minimum form radius that can be
ground using each grit size.
Other factors can affect the surface finish achieved.
In particular:
• Production grinding applications, with higher stock
removal ranges, will give surface finishes at the
coarser end of the range
• Plunge grinding applications will often require the
selection of a grit size one size finer than shown
• Dressing techniques & the type of material can
also affect the surface finish achieved
ACHIEVING IMPROVED SURFACE FINISHES
By changing the wheel dressing technique, it is
possible to achieve finer surface finishes than those
shown. As well as reducing the dresser infeed per
revolution of the grinding wheel, it is also possible
to reduce the infeed and traverse rate when
grinding, thus reducing the stock removal rate.
Obviously this approach will have limited application
in production grinding but it can be very useful in
tool room work.