Sms Screw Manufacturers - Katsuhana Fasteners Corp. Taiwan

Product Introduction

DIN7981 (ISO7049)

DIN7981

Thread size									ST 2.2	ST 2.9	ST 3.5	ST 4.2	ST 4.8	ST 5.5	ST 6.3
P⁴⁾									0.8	1.1	1.3	1.4	1.6	1.8	1.8
a²⁾ max.									0.8	1.1	1.3	1.4	1.6	1.8	1.8
da max.									2.8	3.5	4.1	4.9	5.6	6.3	7.3
dk max. min.									4	5.6	7	8	9.5	11	12
dk max. min.									3.7	5.3	6.64	7.64	9.14	10.57	11.57
k max. min.									1.6	2.4	2.6	3.1	3.7	4	4.6
k max. min.									1.4	2.15	2.35	2.8	3.4	3.7	4.3
r min.									0.1	0.1	0.1	0.2	0.2	0.25	0.25
rʃ =									3.2	5	6	6.5	8	9	10
Cross recess		Recess No.	0	1	2			3
		Type H		m ref.	1.9	3	3.9	4.4	4.9	6.4
				Penetration		min.	0.85	1.4	1.4	1.9	2.4	2.6	3.1
				Penetration		max.	1.2	1.8	1.9	2.4	2.9	3.1	3.6
		Type Z		m ref.	2	3	4	4.4	4.8	6.2	6.8
				Penetration		min.	0.95	1.45	1.5	1.95	2.3	2.55	3.05
				Penetration		max.	1.2	1.75	1.9	2.35	2.75	3	3.5
Y ref.ᶟ⁾		Type C	2	2.6	3.2	3.7	4.3	5	6
Y ref.ᶟ⁾		Type F	1.6	2.1	2.5	2.8	3.2	3.6	3.6
/⁴⁾
Type C				Type F
nom.	min.		max.		min.		max.
4.5	3.7		5.3		3.7		4.5		-	-	-	-	-	-	-
6.5	5.7		7.3		5.7		6.5		-	-	-	-	-	-	-
9.5	8.7		10.3		8.7		9.5		-	-	-	-	-	-	-
13	12.2		13.8		12.2		13		-	-	-	-	-	-	-
16	15.2		16.8		15.2		16		Range		-	-	-	-	-
19	18.2		19.8		18.2		19		Of	-	-	-	-	-	-
22	21.2		22.8		20.7		22		commercial
25	24.2		25.8		23.7		25		Iengths		-	-	-	-	-
32	30.7		33.3		30.7		32
38	36.7		39.3		36.7		38
45	43.7		46.3		43.5		45
50	48.7		51.3		48.5		50

P= pitch of the thread.
Distance from the underside of the head to the first major diameter of the thread within specified limits.
Length of incomplete thread.
Sizes with lengths marked with a dash (一) in the table shall not be manufactured.