
Flowchart : M5 tapping
PD PD
Check 1
Boring before tapping
Engagement ratio on cutting taps
Engagement ratio on roll taps
Min
Internal threads
Min 100%
100%
Max 76.9%
Internal threads
M2s
Internal threads
p
Ta
M3s
Ta
p
Min Max
Max
Length of
engagement=7.6mm 76.9%
74.1%
【Length of engagement】
Internal threads made by roll taps are
M4s
On "middle" engagement class, 7H class can be chosen
in case of "L" engagement length. different from those made by cutting
p Internal threads
Ta Engagement Unit : mm
taps on the shape of minor dimameter.
Symbol
Middle
Coarse
classification Engagement
D1 Unit : mm
Fine
d=5.0mm
Engagement length External threads
Drill size Min
*Hole size for thread forming taps
length classification
(ref.) Max
M5s S Short engagement length 4H 5H − S≦2.5(mm) Min Max
Ta
p
M Normal engagement length 5H 6H 7H 2.5<M≦7.5(mm)
Bored hole size 4.2 4.134 4.334
4.59 4.67
L Long engagement length 6H 7H 8H 7.5<L(mm)
Engagement ratio 92.4% 100% 76.9% Forming condition changes depending
P=0.8mm D1 is minor diameter of JIS 6H(2nd Class) of internal threads on workpiece's Material and shape.
Above is for customer's reference.
M6s
p
Ta
Tolerance area of tap's pitch diameter 【Thread class of cutting taps】
M8s Class PD tolerance
T ap
【Pitch diameter】
P2 20μm〜40μm
Diameter of imaginary cylinder or cone Internal threads
which makes equal the width of threads P3 40μm〜60μm
Check 2
0 and width of space between the threads
M1ps
Ta
P4 60μm〜80μm
P2
P3 P5 80μm〜100μm
2 P4 *Above shows the plus tolerance
M1ps by setting PD basic size as "0".
Ta Width of P5
threads 【Thread class of roll taps】
Width of space
Class PD tolerance
8.5 between threads
-M ps
M1 Ta G6 64μm〜76μm
Pitch
Threading
diameter G6 G7 76μm〜89μm
G7
24 G8 89μm〜102μm
-M s
M9 Tap
G8
*Above shows the plus tolerance
by setting PD basic size as "0".
Basic size of pitch diameter
48 -200μm -150μm -100μm -50μm 4.480mm +50μm +100μm +150μm +200μm
5-M ps
M2 Ta
Ⅱ G6 G7 G8
100
0-M s
P1 P2 P3 P4 P5
M5 Tap Tolerance of dies is the P2
target of external threads
nifi
ed
Class of dies 6g external threads(-119〜-24) 6H internal threads(0〜125)
r U ads
Fo r e s
NR GR GP NP
t h
Ta
p
Ⅱ Solid dies
P1 Solid dies JIS 2Class external threads(-119〜-24) JIS 2Class intenal threads(0〜125)
h
ort
itw
Wh ds P2 for Auto Lathe WR GR GP WP
For threa s
p
Ta Relative position of PD tolerance area of external threads, internal threads, taps and gages.
ed
ds us
threa es
crew hin
For S ing mac )
w
e
on s s(S
p
M
(–) ← Basic size of pitch diameter → (+)
Ta
4.480mm
ds
rea
Unit : μm Unit : μm
e th ps
Pip Ring gage pitch diameter (for external threads inspection) Plug gage pitch diameter (for internal threads inspection)
For Ta
Check 3
NR6g -133 〜 -119 GR6g -33 〜-19 GP6H 2 〜 10 NP6H 125〜133
can
eri WRⅡ -119 〜 -111 GRⅡ -36 〜-28 GPⅡ 4 〜 12 WPⅡ 117〜125
Gage check
Am ds
For threa s
e
pip Ta
p NR : NOT GO ring gage GR : GO ring gage GP : GO plug gage NP : NOT GO plug gage
WR : NOT GO working ring gage WP : NOT GO working plug gage
ure
iat
Unit : mm Unit : mm
Min ds
For threa s Accuracy of external threads Accuracy of internal threads
p
Ta
Major diameter Pitch diameter Minor diameter Major diameter Pitch diameter Minor diameter
6g 4.826〜4.976 4.361〜4.456 − 6H − 4.480〜4.605 4.134〜4.334
JIS 2class 4.826〜4.976 4.361〜4.456 〜3.994 JIS 2Class − 4.480〜4.605 4.134〜4.334
Sizes-14