PD PD

MinMin

Min 100%

100%

MaxMax 74.1%

M2 Taps M3

MaxMax

Min Taps

Max Length of 74.1%74.1%

Length of engagement engagement=4.6mm On "middle" engagement class, 7H class can be chosen M4 in case of "L" engagement length. Internal threads made by roll taps are Engagement different from those made by cutting

Internal threads Taps classification taps on the shape of minor dimameter. Engagement Unit : mm

length D1 Unit : mm

Engagement External threads *Hole size for thread forming taps

length classificationDrill sizeMinMaxM5
(ref.)

S Short engagement length 4H 5H — S 1.5(mm) Min Max

Bored hole size 2.5 2.459 2.599 Taps

MNormal engagement length5H6H7H2.752.82
1.5 M 4.5(mm)Engagement ratio

92.4% 100% 74.1% Forming condition changes depending

L Long engagement length 6H 7H 8H 4.5 L(mm)

P=0.5mm on workpiece's Material and shape. D1 is minor diameter of JIS 6H(2nd Class) of internal threads Above is for customer's reference. M6 Taps

Tolerance area of tap's pitch diameter

M8 Thread class of cutting taps Taps 【Pitch diameter】

Internal threadsClassPD tolerance
Diameter of imaginary cylinder or cone
which makes equal the width of threadsISO224μm〜 40μm

and width of space between the threads M10 ISO2X 39μm〜 55μm Taps *Above shows the plus tolerance

ISO2 by setting PD basic size as "0". ISO2X M12 Width of Width of Taps threadsthreads Thread class of roll taps

Width of space Width of space ClassPD toleranceM1-M
between threadsbetween threadsμm〜μm
ISO2X6476Taps7
Pitch Pitchμ μ
ISO3X76m89 m
diameterdiameter
ISO2XISO2X *Above shows the plus toleranceM9-M
ISO3XISO3X by setting PD basic size as "0".24
Taps
Basic size of pitch diameter
2.675mmM25-M
+50μm -50μm -100μm -150μm +100μm+150μmTaps48
For Unified
ISO2X ISO3X 6gRoll tapsthreads
Taps
Tolerance of dies is theISO2
target of external threadsCutting taps
ISO2XFor Whitworth
Class of diesthreads
6gSolid dies6g external threads()6H internal threads()Taps
-95-200100

NR GRGR GP NP

For Pipe threads Relative position of PD tolerance area of external threads, internal threads, taps and gages. Taps

For Pg threads (–) ← Basic size of pitch diameter → (+) Taps 2.675mm

Unit : m Unit : m Ring gage pitch diameter (for external threads inspection) Plug gage pitch diameter (for internal threads inspection)

NR6g -105 〜 -95 GR6g -23 〜 -13

GP6H 2 10 NP6H 100 108

NR : NOT GO ring gage GP : GO plug gage GR : GO ring gage NP : NOT GO plug gage Unit : mm Unit : mm Accuracy of external threads Accuracy of internal threads

Major diameter Pitch diameter Minor diameter Major diameter Pitch diameter Minor diameter

6g 2.8742.980 2.5802.655 6H 2.6752.775 2.4592.599