DIN 93 Lock Washer with Tab

The tab washer, which conforms in its technical specifications to the German standard DIN 93, is a flat ring with a projection.

The product serves as a locking element in fastening assemblies together with hexagon bolts and nuts. The central hole of the washer is sized to the metric thread diameter in the range M3-M52.

Carbon steel alloys with electroplated zinc coating, stainless steels grades A2, A4, brass, copper, and aluminium are used as raw materials for manufacturing this type of washer.

Existing equivalents of the German standard DIN 93

The tab washer is a common and widely demanded fastener. The product does not have a clearly defined scope of application; it is used in various sectors of the economy related to mechanical engineering and power engineering, instrument making and automotive manufacturing, as well as in everyday use.

Some manufacturers use designations other than the commonly accepted DIN 93 in washer markings. This is not an error: among Russian standards there are normative documents under which practically identical products are manufactured:

1. GOST 13463-77 applies to lock washers with projection, product grade A. The main purpose of these products is to secure nuts and bolts with hexagon heads and metric thread M3-M48.
2. GOST 13464-77 contains requirements for lock washers with tab, product grade A, having reduced dimensions. They are intended for use with fasteners of the same reduced size and thread diameter from 6 mm to 24 mm.

Although these standards are considered equivalents of the German regulation, when selecting fasteners you should confirm the matching parameters with FLOK sales managers.

Technical requirements for DIN 93 washers with tab

DIN 93 washers with tab in the FLOK catalogue fully comply with the specified standard in all parameters. The outer diameter ranges from 12-105 mm, the hole size is 3.2-54 mm. The tab width can be 5-32 mm, and the thickness of the product also varies.

The main purpose of a tab washer installed under the head of a bolt or under a nut is to reinforce the fastening assembly and create a barrier against spontaneous loosening of the joint. The locking effect is created not so much by the washer itself as by the tab. As the fastener is tightened, the tab is bent toward the nut or the head of the bolt/screw/stud into a vertical position.

The use of different metals allows for a more precise definition of the products’ application. Copper and brass washers are intended for specific tasks, serving not only a functional but also a decorative role. Steel washers with tab and electroplated zinc coating are not susceptible to corrosion and work well in conditions of increased humidity. Stainless fasteners can be used in contact with aggressive environments.

How to buy a DIN 93 lock washer with tab

FLOK supplies DIN 93 washers with tab in quantities sufficient for orders of any size. The company works with legal entities and individuals on a wholesale and retail basis.

d	d1	d2	ds	b	L
M5	5.3	17	0.5	6	16
M6	6.4	19	0.5	7	18
M8	8.4	22	0.75	8	20
M10	10.5	26	0.75	10	22
M12	13.0	30	1.0	12	28
M16	17.0	36	1.0	15	32
M20	21.0	42	1.0	18	36
M24	25.0	50	1.0	20	42
M30	31.0	63	1.6	26	52
M36