Designation for washers and machine screws

[JSten]

I'm organizing the chaos of machine screws and washers out in the workshop. As part of this, I've totally nerded out on the naming for screw heads, nuts, and washers. By naming, I mean the letters that often appear in the product name. For example, if I have an M6 60mm M6SF, it's an M6 that is 60mm long with a hex flange head:

or if I say MC6S it's a cylindrical socket head:


So far, I've concluded that the letters are decoded in the following order (entirely based on googling):
* Initial M stands for metric, and U for inch
* Then comes the shape, 6S = hexagonal, C = cylindrical, R = round, F = countersunk, K = dome, KF = dome-countersunk
* Then "bits" S = slot, X = Phillips or Pozidriv, T = torx, 6S = hex socket
* Finally, any additional attributes, such as F = flange

Nuts are similar:
* First M = metric, U = inch
* Optional L = low
* Number of sides, or V = wing
* Always an M, as in mutter (nut)(?)
* Any additional attributes F = flange, FT = serrated flange

For example:
* ML6M is a low hex nut
* M6LM is a hex nut with nylon insert/lock
* MVM is a wing nut
* M6MFT is a hex nut with a serrated flange

Washers are a bigger question mark, for example, what is the difference between RB and BRB... Or why not an RBS, SRKB, TBRSUB, etc.

Now to my question, does anyone have a complete (or better insight) into what the different letters mean? I've searched and searched, but there doesn't seem to be any decent guide online, especially concerning washers. Of course, you can find a ton of names through image searches or by navigating Arvid-Nilson's website (https://shop.arvidnilsson.com/sv/). Unfortunately, it's not the most convenient way to get an overview, and it's not always obvious what a letter combination stands for, even if you can make a qualified guess in most cases.

 

[fb35523]

I believe this is described in the standard ISO 225:2010 which unfortunately costs 1195 kr. It would be quite interesting if you found a cheaper list!

 

[tobiast]

What does your need look like, do you need to know the standard designation for washers to be able to order, are you going to manufacture, or why do you want to explore this almost impenetrable jungle of standards and designations? Each type of washer has a standard designation (DIN, ISO, ANSI, BS etc. + number) and then an indication, sometimes of one or more letters to indicate diameter and thickness. A is thus the lowest measure and G (e.g., for British Standard/BS) is the highest measure.

This link might help a little, but a transfer table between standards and designations might be trickier to find.

https://www.fastenerdata.co.uk/fasteners/washers.html

 

[JSten]

Thanks for the responses. Argh, it looks like ISO 225:2010 is the key here, these darn standards that you have to pay for, annoying...

What are your needs, do you need to know the standard designation for washers to be able to order, are you going to manufacture, or why do you want to explore this almost impenetrable jungle of standards and designations?

Mainly, it's to satisfy my curiosity about what the different designations stand for. But, as I mentioned, I'm also going through all the stuff I have, and it would be nice to sort and label them a bit more neatly than coming up with something myself.

Perhaps I should add that I recently bought a larger quantity of machine screws and washers at a bankruptcy auction. So, my stuff isn't just a handful of leftover screws but maybe 200-300 different piles/boxes/containers with various screws. Some are labeled, but the vast majority are not...

Again, thank you so much for your responses!