UNI 8842

Tooth Washer

Lock washer with internal or external teeth — UNI 8842.

Tooth Washer — technical drawing with reference dimensions
d1d2shn
Size d1 d2 s Height h n Weight /100
1.6 1.7 3.6 0.30.9 90.0019 kg
1.8 2.0 4.0 0.30.9 90.0022 kg
2 2.2 4.5 0.30.9 90.0029 kg
2.2 2.4 5.0 0.41.2 90.0047 kg
2.5 2.7 5.5 0.41.2 90.0057 kg
3 common 3.2 6.0 0.41.2 90.0064 kg
3.5 3.7 7.0 0.51.5 100.0109 kg
4 common 4.3 8.0 0.51.5 110.0140 kg
5 common 5.3 10.0 0.61.8 110.0266 kg
6 common 6.4 11.0 0.72.1 120.0345 kg
7 7.4 12.5 0.82.4 140.0501 kg
8 common 8.4 15.0 0.82.4 140.0762 kg
10 common 10.5 18.0 0.92.7 160.1186 kg
12 common 13.0 20.5 1.03.0 160.1549 kg
14 common 15.0 24.0 1.03.0 180.2164 kg
16 common 17.0 26.0 1.23.6 180.2863 kg
18 19.0 30.0 1.44.2 180.4652 kg
20 common 21.0 33.0 1.44.2 200.5593 kg
22 23.0 36.0 1.54.5 200.7093 kg
24 common 25.0 38.0 1.54.5 200.7574 kg
27 28.0 44.0 1.64.8 221.1364 kg
30 31.0 48.0 1.64.8 221.3248 kg

All dimensions in mm. Weight figures are indicative (steel), per 100 pieces.

Glossary

d1
Inner (hole) diameter
d2
Outer diameter
s
Wrench size (across flats)
h
Height / thickness
n
Number of teeth

Frequently asked questions

What standard governs the tooth washer?

UNI 8842 — the dimensions in the table below (nominal diameter, thread pitch and all fixed geometry) are taken directly from that standard.

Are these dimensions in millimetres?

Yes — all values are in mm, matching the metric ISO/UNI standards these components are drawn from. There are no imperial variants in this table.

What is the difference between d1/d2 and the nominal size?

The nominal size (used in the designation, e.g. "10") matches the bolt or screw diameter the washer is meant for. d1 is the actual hole diameter (slightly larger than nominal, for clearance) and d2 is the outer diameter of the washer.

References & further reading

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