Square Washer

Square Washer – Product Details

JMIKS Fasteners supplies square washers in SS 304, SS 316 and SS 202 for bolt sizes M8 to M36 and 5/16″ to 1-1/4″ BSW, to DIN and IS standards. A square washer gives a large, flat seat under the nut or bolt head.

Specifications

Standard : DIN 436 / IS / AISI
Size : Metric- M8 to M36, BSW – 5/16 to 1.1/4″
Grade : SS304 | SS316 | SS202

What Is a Square Washer?

A square washer is a flat plate, square in shape, with a round hole in the centre. Its large area spreads the clamping load over soft material such as timber, and its straight edges sit flat against angles and channel walls, so the washer does not turn while the nut is tightened. Square washers for timber work are made to DIN 436, which covers M10 to M30 bolts; other sizes are supplied to your drawing.

Applications

Timber structures, wooden frames and roof trusses
Solar mounting structures and strut channels
Steel fabrication with slotted holes
Column base plates and foundation bolts
Cable tray and pipe supports

Square Washer FAQs

Square washer or round plain washer?

A round plain washer suits most steel joints. A square washer is used where the load must be spread over a larger area, such as timber, or where the washer must sit against a straight edge without turning.

Can square washers be used on slotted holes?

Yes. A square washer covers a long slot better than a round washer of the same size, so the nut gets a full, flat seat.

Which grade should I choose?

SS 304 suits most indoor and outdoor work, SS 316 is used near the sea and around chemicals, and SS 202 is an economical choice for dry indoor use. Use the same grade as the bolt and nut.