Add Keps nuts and Sems screws to Content Center fasteners

[whinkle]

It'd be lovely if the Content Center fasteners included Keps hex nuts and Sems screws, even if just the basic imperial and metric machine screw sizes.  Aside from just being easily available for assemblies, they'd then be selectable for use in Bolted Connections, and also show up on Parts Lists/BOMs are discrete purchasable components.  Put an intern to work on it next summer!

[swalton]

What are Keps nuts and Sems screws? 

Please add links to the ASME/ISO standards or vendor website.

[whinkle]

I suppose "k-lock nut" would be more generic, as "Keps" is an ITW-Shakeproof trademark, apparently.

"A Keps nut, (also called a k-lock nut or washer nut), is a nut with an attached, free-spinning washer.

It is used to make assembly more convenient. Common washer types are star-type lock washers, conical, and flat washers."  (Wikipedia) See also McMaster-Carr .

I'm unaware of a specific ASME//ANSI/ISO standard for these beyond that for the component machine hex nut and washer (e.g. ANSI B18.2.2,, B18.21.1), though there is reportedly a Shakeproof standard # 501-01 - but here is an examplar of the spec table used by a number of vendors:  Nuts - K-lock

Similarly, a SEMS Screws (aka SEM Screws) is a machine screw with an integrated free-spinning lock washer, commonly internal-tooth but also available with external-tooth or spring washers, etc.  Again, widely available from a variety of manufacturers/vendors.  See McMaster-Carr .

Again, no specific ASME/ANSI/ISO spec that I know of.  A vendor spec for a variety of SEMS screws: Screws - SEMS