5/16-18 Stainless Hex Head Cap Screws

5/16-18 hex head cap screws with USS coarse (UNC) thread, made from 18-8 stainless steel. We stock 1/2", 3/4", 1", 1-1/4", 1-1/2", 1-3/4", 2", 2-1/4", 2-1/2", 2-3/4", 3", 3-1/2", 4", 4-1/2", 5", 6" lengths. They take a 1/2" wrench. Short lengths are fully threaded and longer lengths partially threaded.

Hex Head Cap Screw Stainless | The Nutty Company, Inc.

Specifications

Size: 5/16-18 (USS coarse)
Lengths: 1/2", 3/4", 1", 1-1/4", 1-1/2", 1-3/4", 2", 2-1/4", 2-1/2", 2-3/4", 3", 3-1/2", 4", 4-1/2", 5", 6"
Wrench size: 1/2"
Thread: USS coarse (UNC)
Material: 18-8 stainless steel

The length of a cap screw is measured from the under-head bearing surface to the extreme end of the screw.
(FT)=Full Thread | (PT)=Partial Thread
Thread Length on a 5/16-18 bolt is approx. 7/8"
Wrench Size = 1/2"

Common Uses

Outdoor and marine assemblies
Food and process equipment
Corrosive and washdown areas

FAQ

What nut fits a 5/16-18 stainless cap screw?
A 5/16-18 18-8 stainless hex nut, or a nylon insert lock nut where vibration is a concern, with a 5/16" stainless flat washer.

How do I stop stainless threads from galling?
Stainless threads can seize (gall) when tightened fast or under heavy load. Put anti-seize on the threads, tighten slowly at low speed, keep the threads clean and don't overtighten.

How strong are 18-8 stainless bolts?
18-8 stainless bolts to ASTM F593 have a minimum tensile strength of about 100,000 psi in 1/4" to 5/8" and about 85,000 psi in 3/4" to 1-1/2". That is stronger than Grade 2 steel but not as strong as Grade 5 or Grade 8.

Free shipping on orders over $100, and orders placed before noon EST ship the same day. Purchase orders are accepted from government agencies, schools, hospitals, municipalities and companies with established credit with The Nutty Company, Inc.