External Tooth Lock Washers

Additional information

DIN 6797 A External Tooth Lock Washers have twisted prong teeth on the largest radius, which results in superior torsional resistance, and are the preferred tooth-type lock washer when the greatest locking ability is desired. However, they are primarily suited for large diameter heads, like pan, because the teeth must contact both the fastener and mating surface; the teeth and surface indentations they create will likely be visible. Spring steel with a zinc plated and plain finish (unplated and susceptible to rust), along with stainless steel, can be supplied. Size is nominal hole size, so select a washer that matches the screw size (if you have an M6 screw, select an M6 washer for example). They may be listed as DIN 6797 Type A.

Size	1.7	2.2	2.7	3.2	3.7	4.3	5.3	6.4	7.4	8.4
d	min=nominal size		1.7	2.2	2.7	3.2	3.7	4.3	5.3	6.4	7.4	8.4
max		1.84	2.34	2.84	3.38	3.88	4.48	5.48	6.62	7.62	8.62
dc	max=nominal size		3.6	4.5	5.5	6	7	8	10	11	12.5	15
min		3.3	4.2	5.2	5.7	6.64	7.64	9.64	10.57	12.07	14.57
t	0.3	0.3	0.4	0.4	0.5	0.5	0.6	0.7	0.8	0.8
Number of Teeth	6	6	6	6	6	8	8	8	8	8
per 1000 units≈kg	0.01	0.025	0.04	0.045	0.075	0.095	0.18	0.22	0.3	0.45
For Nominal Thread Diameter	M1.6	M2	M2.5	M3	M3.5	M4	M5	M6	M7	M8
Size	10.5	13	15	17	19	21	23	25	28	31
d	min=nominal size		10.5	13	15	17	19	21	23	25	28	31
max		10.77	13.27	15.27	17.27	19.33	21.33	23.33	25.33	28.33	31.39
dc	max=nominal size		18	20.5	24	26	30	33	36	38	44	48
min		17.57	19.98	23.48	25.48	29.48	32.38	35.38	37.38	43.38	47.38
t	0.9	1	1	1.2	1.4	1.4	1.5	1.5	1.6	1.6
Number of Teeth	9	10	10	12	12	12	14	14	14	14
per 1000 units≈kg	0.8	1	1.6	2	3.5	3.8	5	6	8	9
For Nominal Thread Diameter	M10	M12	M14	M16	M18	M20	M22	M24	M27	M30