Contact Platform Support
Help Center
Related Products
The term cap screw refers to many different things at different times and places. Currently, it most narrowly refers to a style of head (see the gallery below). More broadly, and more commonly, it refers to the group of screws: shoulder screws, hex heads, counter-sunk heads, button heads, and fillister heads. In the US, cap screws are defined by ASME B18.6.2 and ASME B18.3. In the past, the term cap screw, in general, referred to screws that were supposed to be used in applications where a nut was not used, however the characteristics that differentiated it from a bolt vary over time. In 1910, Anthony defined it as screw with a hex head that was thicker than a bolt head, but the distance across the flats was less than a bolt's. In 1913, Woolley and Meredith defined them like Anthony, but gave the following dimensions: hex head cap screws up to and including 7⁄16 inch (11.1125 mm) have a head that is 3⁄16 inch (4.7625 mm) larger than the shank diameter; screws greater than 1⁄2 inch (12.7 mm) in diameter have a head that is 1⁄4 inch (6.35 mm) larger than the shank. Square head cap screws up to and including 3⁄4 inch (19.05 mm) have a head 1⁄8 inch (3.175 mm) larger than the shank; screws larger than 3⁄4 inch (19.05 mm) have a head 1⁄4 inch (6.35 mm) larger than the shank. In 1919, Dyke defined them as screws that are threaded all the way to the head.
A socket cap screw, also known as a socket head capscrew, socket screw, or Allen bolt, is a type of cap screw with a cylindrical head and hexagonal drive hole. The term socket head capscrew typically refers to a type of threaded fastener whose head diameter is nominally 1.5 times that of the screw shank (major) diameter, with a head height equal to the shank diameter (1960 series design). Forged heat-treated alloy examples are high strength fasteners intended for the most demanding mechanical applications, with special alloy formulations available that are capable of maintaining strength at temperatures in excess of 1000 degrees F (587 degrees C).
In addition to the 1960 series design, other head designs include low head, button head and flat head, the latter designed to be seated into countersunk holes. A hex key (sometimes referred to as an Allen wrench or Allen key) or hex driver is required to tighten or loosen a socket screw. Socket head capscrews are commonly used in assemblies that do not provide sufficient clearance for a conventional wrench or socket.
Send Inquiry to This Supplier
You May Also Like
-
Safe Top Nails Plastic Cap Roofing Nails Ring Shank Spiral Shank Umbrella Head With WasherNegotiableMOQ: 1 Ton -
Fit R175-C Roofing Coil Nailer Roofing NailsUS$ 15 - 32MOQ: 100 Cartons
-
Made in China Very Cheap Plastic Expand Nails ManufacturerUS$ 0.001 - 0.02MOQ: 10000 Pieces
-
Hard Copper Clout Nails Copper NailUS$ 0.0001 - 0.1MOQ: 50000 Pieces
-
Cup Head Weld PinsNegotiableMOQ: 1 Ton
-
Stainless Steel Materials Precision Turning Parts / Die Casting MachiningNegotiableMOQ: 1 Ton
-
Insta Hang ,nail With Hooks Kit,pegsUS$ 2 - 4MOQ: 3000 Sets
-
THUMB TACKSNegotiableMOQ: 10000 Boxes
-
All Kinds of Standard Black Concrete Nail Concrete Steel NailUS$ 456 - 465MOQ: 1 Ton
-
Common Wire NailsUS$ 700 - 900MOQ: 500 Kilograms
