Commonly used head shape dimensions





Screw heads have various functions such as workability, weight reduction, and resistance to loosening. In this issue, we will introduce commonly used head shapes and publish the No. 0 and JIS head shape dimension tables, which are very important for quality control.



No. 0 cross-recessed screw head shape dimensions

・Let Q be the depth to which the gauge sinks into the cross-hole.
・The eccentricity F of the head is assumed to be the eccentricity with respect to the center of the axis.
・0 cross-recessed shape dimensions are based on JISB1012 type S.



Diagram of Type 1, Type 2, and Type 3






Pan Head

 

(unit：mm)
Recess  Type Nominal Diameter Ｄ Ｈ m Ｑ ※F ※G
d Standard Dimension Tolerance Standard Dimension Tolerance Reference min～Max Max Max
No. 0 Type 1 ※M1.2 1.8 +0.05
-0.1		 0.45 ±0.05 1.3 0.30～0.50 0.1 2°
M1.4 2.0 0.5 1.55 0.51～0.74
(M1.6) 2.4 0
-0.14		 0.55 0
-0.1		 1.65 0.56～0.84
M1.7 2.5 +0.05
-0.1		 0.5 ±0.05 1.7 0.61～0.89
M2 3.0 +0.05
-0.2		 0.6 ±0.08 2 0.91～1.21
M2.3 3.5 0.7 2.2 1.06～1.41 0.15
(M2.5) 3.8 0
-0.25		 0.9 0
-0.14
M2.6 4.0 +0.05
-0.2		 0.8 ±0.08
 Type 2 M1.2 2.0 +0.05
-0.1		 0.45 ±0.05 1.3 0.30～0.50 0.1 2°
M1.4 2.5 0.5 1.55 0.51～0.74
M1.6 2.8 0
-0.14		 0.55 0
-0.1		 1.65 0.56～0.84
M1.7 3.0 +0.05
-0.1		 0.5 ±0.05 1.7 0.61～0.89
M2 3.5 +0.05
-0.2		 0.6 ±0.08 2 0.91～1.21
Type 3 ※M1.2 2.0 +0.05
-0.1		 0.7 ±0.05 1.35 0.35～0.53 0.1 2°
M1.4 2.5 0.8 1.65 0.56～0.84
(M1.6) 2.8 0
-0.14		 0.85 0
-0.1		 1.8 0.71～1.00
M1.7 3.0 +0.05
-0.1		 0.9 ±0.05 1.9 0.81～1.10
M2 3.5 +0.05
-0.2		 1 ±0.08 2.1 1.01～1.31
M2.3 4.0 1.1 2.2 1.06～1.41 0.15
(M2.5) 4.3 0
-0.25		 1.3 0
-0.14
M2.6 4.5 +0.05
-0.2		 1.2 ±0.08

 

 

Flat Head

 

(unit：mm)
Recess Type Nominal Diameter Ｄ Ｈ m Ｑ ※F ※G C
Reference range
d Standard Dimension Tolerance Standard Dimension Tolerance Reference min～Max Max Max
No. 0 Type 1 M1.2 1.8 +0.05
-0.1		 0.40 0
-0.05		 1.35 0.35～0.53 0.1 2° 0.1
M1.4 2.0 0.45 1.55 0.51～0.74 0.15
(M1.6) 2.4 0
-0.14		 0.50 1.65 0.56～0.84
M1.7 2.5 +0.05
-0.1		 0.50 1.7 0.61～0.89
M2 3.0 +0.05
-0.2		 0.60 0
-0.08		 2 0.91～1.21 0.1
M2.3 3.5 0.70 2.2 1.06～1.41 0.15
(M2.5) 3.8 0
-0.25		 0.80
M2.6 4.0 +0.05
-0.2		 0.80 0
-0.1
Type 3 M1.2 2.0 +0.05
-0.1		 0.50 0
-0.05		 1.35 0.35～0.53 0.1 2° 0.15
M1.4 2.5 0.70 1.65 0.56～0.84
(M1.6) 2.8 0
-0.14		 0.80 1.8 0.71～1.00 0.2
M1.7 3.0 +0.05
-0.1		 0.80 1.9 0.81～1.10 0.15
M2 3.5 +0.05
-0.2		 0.90 0
-0.08		 2.1 1.01～1.31
M2.3 4.0 1.00 2.2 1.06～1.41 0.15
(M2.5) 4.3 0
-0.25		 1.10
M2.6 4.5 +0.05
-0.2		 1.10

 

 


head shape dimensions

（JIS B 1111 Anex：Type, Shape and Dimensions Product specifications are the same as ISO 7045:2011，ISO 7046-1:2011，ISO 7046-2:2011，ISO 7047:2011，ISO 7048:2011）




Nominal Diameter

 pitch Recess Pan Head Flat Head Oval Head
dk k dk k dk k + f
d P Standard Dimension Tolerance Standard Dimension Tolerance Standard Dimension Tolerance Standard Dimension Tolerance Standard Dimension Tolerance Standard Dimension Tolerance
M2 0.4 No.1 3.5 0
-0.4		 1.3 ±0.1 4 0
-0.4		 1.2 0
-0.2		 4 0
-0.4		 1.6 0
-0.4
M2.2 0.45 4 1.5 4.4 1.3 4.4 1.8
M2.3 0.4 4 1.5 4.6 1.35 4.6 1.85
M2.5 0.45 4.5 1.7 5 1.45 5 2.05
M2.6 0.45 4.5 1.7 5.2 1.5 5.2 2.1
M3 0.5 No.2 5.5 0
-0.5		 2 ±0.15 6 0
-0.5		 1.75 0
-0.3		 6 0
-0.5		 2.45 0
-0.5
M3.5 0.6 6 2.3 7 2 7 2.8
M4 0.7 7 2.6 8 2.3 8 3.2
M4.5 0.75 8 0
-0.6		 2.9 9 0
-0.6		 2.55 9 0
-0.6		 3.55
M5 0.8 9 3.3 10 2.8 10 4
M6 1 No.3 10.5 0
-0.7		 3.9 ±0.2 12 0
-0.7		 3.4 0
-0.4		 12 0
-0.7		 4.8 0
-0.6
M8 1.25 14 0
-0.8		 5.2 16 0
-0.8		 4.4 16 0
-0.8		 6.2


Nominal Diameter pitch Recess Truss Head Bind Head
dk k dk k + f
d P Standard Dimension Tolerance Standard Dimension Tolerance Standard Dimension Tolerance Standard Dimension Tolerance
M2 0.4 No.1* 4.5 0
-0.4		 1.2 ±0.1 4.3 0
-0.4		 1.2 ±0.15
M2.2 0.45 5 1.3 4.7 1.3
M2.3 0.4 5.2 1.4 4.9 1.4
M2.5 0.45 5.7 1.5 5.3 1.5
M2.6 0.45 5.9 1.6 5.5 1.6
M3* 0.5 No.2* 6.9 0
-0.5		 1.9 ±0.15 6.3 0
-0.5		 1.9 ±0.2
M3.5 0.6 8.1 2.2 7.3 2.2
M4 0.7 9.4 2.5 8.3 2.5
M4.5 0.75 10.6 0
-0.6		 2.8 9.3 0
-0.6		 2.8
M5 0.8 11.8 3.1 10.3 3.1
M6 1 No.3 14 0
-0.7		 3.7 ±0.2 12.4 0
-0.7		 3.7
M8 1.25 17.8 0
-0.8		 4.8 16.4 0
-0.8		 4.8 ±0.3

*Truss head M3 recess is No.1