GOST 11651-80 Self-Tapping Screws With Raised Countersunk Head and Pointed End

Self-Tapping Screws

With Raised Countersunk Head and Pointed End

For Metal and Plastic

GOST 11651-80*

SELF-TAPPING SCREWS WITH RAISED COUNTERSUNK HEAD AND POINTED END FOR METAL AND PLASTIC Construction and dimensions Self-tapping raised countersunk head and sharpening end screws for metals and plastics. Construction and dimensions	GOST 11651-80* Supersedes GOST 10620-63, GOST 11651-65, in respect of screws with a pointed end

Effective date: 01.01.82.

1. This standard applies to self-tapping screws with raised countersunk head and pointed end for metal and plastic, product grade B, with nominal thread diameter from 2.5 to 8 mm.

2. The design and dimensions of the screws shall conform to those shown in the drawing and in Tables 1, 2.

Type 1

Type 2

---

*Reference dimension.

Table 1

Dimensions in mm

Nominal thread diameter d		2.5	3	4	5	6	8
Thread pitch P		1.25		1.75	2.0	2.5	3.5
Head diameter D	Nom.	4.7	5.6	7.4	9.2	11.0	14.5
	Tolerance per h14	-0.30		-0.36		-0.43
Head height, K, max		1.50	1.65	2.20	2.50	3.00	4.00
Sphere height f≈		0.60	0.75	1.00	1.25	1.50	2.00
Head sphere radius R₁≈		5.4	6.0	8.0	9.4	12.0	15.0
Slot width h	Nom.	0.6	0.8	1.0	1.2	1.6	2.0
	Min	0.66	0.86	1.06	1.26	1.66	2.06
	Max	0.80	1.00	1.20	1.51	1.91	2.31
Slot depth t	Min	1.0	1.2	1.6	2.0	2.4	3.2
	Max	1.2	1.45	1.9	2.3	2.8	3.7
Runout tolerance in a specified direction (2IT14)		0.60		0.72		0.86
Tolerance of slot symmetry relative to the shank, diametral (2IT14)		0.50		0.60			0.72
Cross recess number		1		2		3
Cross recess diameter m, max		3.0	3.3	4.6	5.3	7.2	8.7
Cross recess depth h		1.50	1.80	2.10	2.85	3.20	4.65
Gauge penetration depth into cross recess	Max	1.6	1.9	2.4	3.1	3.7	5.2
	Min	1.3	1.6	1.9	2.6	3.2	4.7
Thread run-out, max		0.8			1.0

Note. The cross recess is per GOST 10753-80.

Table 2

mm

Screw length l		Nominal thread diameter d
Nom.	Tolerance per js17	2.5	3	4	5	6	8
6	± 0.75			-	-	-	-
8					-	-	-
10						-	-
12	± 0.90						-
14							-
16
(18)				Standard lengths
20	± 1.05	-
(22)		-	-
25		-	-
30		-	-
35	± 1.25	-	-
40		-	-	-
45		-	-	-
50		-	-	-	-

Note. Lengths l shown in brackets are not recommended for use.

Designation example:

screw of version 1, diameter 5 mm, length 30 mm, material group 01, without coating, with coarse thread pitch

Screw 5×30.01 GOST 11651-80

Same, version 2, diameter 5 mm, with coarse thread pitch, length 30 mm, made from material group 01, with zinc coating 6 µm thick, chromated

Screw 2-5×30.01.016 GOST 11651-80

3. Technical requirements, thread, test methods, acceptance rules, packaging and marking - as per GOST 10618-80.

4. The theoretical mass of the screws is given in Reference Appendix 1.

APPENDIX 1

For reference

Theoretical mass of self-tapping screws

Screw length l, mm	Nominal thread diameter d, mm
	2.5	3	4	5	6	8
	Mass of 1000 pcs of steel screws with coarse thread pitch, kg ≈
6	0.23	0.35	-	-	-
8	0.29	0.43	0.85	-	-
10	0.35	0.51	0.99	1.60
12	0.40	0.59	1.13	1.82	2.89
14	0.46	0.67	1.27	2.04	3.22
16	0.52	0.75	1.41	2.26	3.55	5.21
18	0.57	0.83	1.55	2.48	3.88	5.78
20	-	0.91	1.69	2.70	4.21	6.35
22	-	-	1.83	2.92	4.54	6.92
25	-	-	2.04	3.25	5.03	7.77
30	-	-	2.32	3.80	5.84	9.19
35	-	-	2.60	4.35	6.65	10.61
40	. -		-	4.90	7.46	12.03
45	-	-	-	5.45	8.27	13.45
50	-	-	-	-	9.08	14.87

Equivalent to DIN 7983, ISO 7051.