Different Types of Socket Screws

A socket screw is a screw which is widely used in the industrial sector and assembly lines. Known by many names but the most common are Hex or Allen head screws. They are widely used because they are some of the strongest screws available (link to Tensile Strength and Torque specification chart), inexpensive, and very easy install using a hexagonal shaped wrench.  This makes them ideal for many applications where space is an issue.  Socket screws are found in various grades of Steel, Stainless Steel and Marine Grade Stainless Steel options.

Types of Socket screws – Matching Metric DIN or ISO number:

• Socket Head Cap – DIN 912
• Low head Socket Cap – DIN 7984
• Button head Socket Cap – ISO 7380
• Flat Head Socket Cap (Countersunk) – DIN 7991
• Socket set screw – DIN 916

Socket Head Cap Screws – Deep hex recess and thick side walls make these the strongest of the socket screw line with the highest preload ratings.  This is one of the most common socket screws you will find.

Low Head Socket Cap Screws – Head height 50% lower than traditional socket cap screw. Great fit where the use of a traditional Socket Head cap is unable to be used due to height restrictions. Since the head height is reduced, maximum preload is much less and therefore not a direct substitution for traditional Socket Head Cap screws.

Button Head Socket Cap Screws – Rounded head profile makes these an ideal candidate for safety use where other screws or bolts may snag clothing or other items on moving machinery.

Flat Head Socket Cap Screws – Flat head screws are countersunk and expose none of their head above the mating surface.  These are often used for assembling close tolerance machinery where head height is critical.

Socket Set Screw – Socket Set Screws are designed to be used where permanent or adjustable locations of components on shafts is required.