Looking for info on grades or classes of SS bolts 1

[erasmu]

I have found in Machinery's Handbook a chart that gives me good information about grade identification marks and mechanical properties of bolts and screws. This is good information for steels. Is there any similar info available for stainless steel bolts? We are having problems with some ss bolts. I would like to identify what we have received and determine what should be specified, as well as how to identify it. Thank you.

 

[CoryPad]

The definitive documents will be industry standards. Some common ones include:

ASTM A 193/193M, A 453/453M, A 962/962M, F 738M

ISO 3506-1




Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[threaded]

You could try contacting The Fastener Engineering and Research Association. Data files 5 and 6 are extremely helpful for selecting stainless steel fasteners.

http://www.fera.org.uk/

Regards, Nuno.

 

[Paskenell]

Besides the spec's that CoryPad has supplied you, ASTM F593 is a popular stainless bolt spec. Erasmu, if you can advise all of the headmarkings on the bolts you are having problems with I might be able to help you with some background on the fastener - ie mfg, specification the mfg meant it to meet, etc.

 

[unclesyd]

Check out this website. Make sure to chek out the technical side. Don't let the name fool you as this is a very well maintained and up to date website. The company is a very respected supplier of Stainless Fasteners as well.

http://www.marfas.com

 

[erasmu]

Paskenell, the bolts that are in question have S30400 on the head along with the letters THE. There are no other markings on the heads. These are 5/16-18 bolts. Can you tell me anything more about them? Thank you.

 

[Paskenell]

These bolts were manufactured by Tong Hwei Enterprises of either Malaysia, China, or most likely, Taiwan. As to the S30400 specification, these bolts are marked to show they were made from 304 stainless steel. These bolts can be represented and sold as 304 stainless steel or 18-8 stainless steel.

Not sure what the problem you are having is, but a comparable fastener would be to purchase the bolts to a ASTM F593C spec. Pricing is comparable and a benefit you gain is a bolt manufactured to the strict requirements of the F593C spec. This would also mean the bolt falls under the FQA (Fastener Quality Act) umbrella.

Hope this helps you.

 

[Billybaru]

Paskenell is correct. The bolts are made by Tong Hwei and very likely in Taiwan. They are a large manufacturer of stainless steel bolts and supply worldwide. ASTM F593 contains many types of SS materials for bolts and is a common spec used in the industry.

Note, the 304SS bolts (ASTM F593C) do not fall under the Fastener Quality Act. The FQA essentially applies to through hardened nuts, bolts (and DTI's) to consensus standards that require both mfg ID and grademarking. 304SS bolts, as we know, are not through hardened.