Crosshead C/sunk Self Tapping Screws (DIN 7982) Pan Crosshead Self Tapping Screws (DIN 7981)

A2-70 grade stainless steel - also known as grade 304 or 18/8. A general purpose grade of stainless steel. A4-70 grade stainless steel - also known as grade 316 or 18/8/3. A higher corrosion resistant, marine grade of stainless steel.

Thread galling mainly occurs with fasteners made of aluminium, titanium, stainless steel, and other alloys which self-generate an oxide surface film for corrosion protection. Galling can occur when excessive pressure is used to tighten a nut onto a thread. In our experience this is observed most on assemblies utilising Nyloc nuts.

The two most commonly produced grades of stainless steel are 304 (known as 'A2') and 316 (known as A4). Both of these grades will offer excellent corrosion resistance, cleanability, and the ability to handle extremely low (cryogenic) and high temperatures.

Stainless steel is principally known and considered for use because of its high level of corrosion resistance in both wet and dry conditions, particularly in comparison with standard carbon steels.

A2 - The most commonly produced grade of stainless steel. Also known as grade or type 304.A4 - The second most commonly produced grade of stainless steel. Also known as grade or type 316.A/F - A shortened form of 'width across flats'.Acorn Nut - Another name for a dome nut.Allen Key - A tool with a hexagonal cross section used for tightening up screws with a socket head.Allthread - A metal bar that has a thread all along its length.

The following table describes the strength specifications for the different property classes of metric steel bolts, screws and studs:

The following table lists the most popularly used threaded fasteners used today, and the DIN standard or otherwise to which they have been designed: DIN 84 Slotted Cheesehead Machine Screw DIN 125 A Form A Flat Washer DIN 125 B Form B Flat Washer DIN 137 Spring Wave Washer DIN 315 Wing Nut - American Form