DIN 7981 Self-Tapping Screw with Round Head, TORX

Self-tapping screws with round head and cross recess, pointed and blunt-tipped, for sheet metal, wood and plastic, DIN 7981. There are two design types: form C — pointed, form F — with blunt tip. Besides tip shapes, recess types also vary.

DIN 7981 self-tapping screw with round head

Self-tapping screws are manufactured with Phillips (PH) recess — cross, Pozidriv (PZ) recess — combination recess, and TORX recess — star-shaped recess. These screws have a cross recess and are widely used in industrial, manufacturing and construction fields for assembling structural parts. When installing into wood or plastic structures, pre-drilling is not required; when installing into metal structures, drilling is necessary. When installing into concrete, brick and plasterboard, expansion wall plugs must be used. This type of self-tapping screw is manufactured using a special technology and has a zinc-plated surface.

Applications

The DIN 7981 C self-tapping screw is used in construction and mechanical engineering for fastening products and materials to metal sheets and frames: without pre-drilling — up to 0.9 mm thick, with pre-drilling — up to 6 mm. It has a tight, self-tapping single-start or double-start thread. The DIN 7981 C self-tapping screw is made of carbon electro-galvanized, yellow passivated steel or stainless steel.

Size table

k	2.2	2.6	2.8	3.05	3.55	3.95	4.55
d1	5.6	6.9	7.5	8.2	9.5	10.8	12.5
n:o	1	2	2	2	2	3	3

L (mm)	d
	2.9	4.2	4.8	6.3
16
19
25
32
38
50

Used in construction and mechanical engineering for fastening products and materials to metal sheets and frames: without pre-drilling — up to 0.9 mm thick, with pre-drilling — up to 6 mm. It has a tight, self-tapping single-start or double-start thread. The DIN 7981 C self-tapping screw is made of carbon electro-galvanized, yellow passivated steel or stainless steel.

Dimensions of DIN 7981 (ISO 7049) round head self-tapping screws, mm

d	ST2.2	ST2.9	ST3.5	ST3.9	ST4.2	ST4.8	ST5.5	ST6.3
dk DIN/ISO	4.2/4.0	5.6	6.9/7.0	7.5	8.2/8.0	9.5	10.8/11.0	12.5/12.0
k DIN/ISO	1.8/1.6	2.2/2.4	2.6	2.8	3.05/3.1	3.5/3.7	3.95/4.0	4.55/4.6
PH, PZ	1	1	2	2	2	2	3	3
y form C	2	2.6	3.2	3.5	3.7	4.2	5	6
y form F	1.6	2.1	2.5	2.7	2.8	3.2	3.6	3.6

Designations:

d — thread diameter

dk — round head diameter

k — head height, max

PH, PZ — cross bit size

y — tip length