Socket Screws & Fasteners
Socket Fasteners
Socket products are fasteners that have an internal hex drive for use with a hex key, or Allen wrench, which requires very little clearance around the fastener. Socket fasteners include screws, bolts, set screws and shoulder bolts. Socket products are widely used in industrial production and assembly lines, including automotive, furniture manufacture, machine tooling applications and steel fabrication.
Socket Head Cap Screw
ASTM A574 socket head cap screws (also known as Allen head screws) have a cylindrical head with a flat chamfered top surface, knurled cylindrical sides and hexagonal recess. A key feature in the design of ASTM A574 socket head cap screws is the ability of the head to sit down into a recess, as no clearance around the OD of the head is required for wrenching.
Flat Head (Countersunk) Cap Screw
Countersunk ASTM F835 flat head cap screws are designed to recess into an 82° counter bore for a flush installation, with the hex key offering a more effective drive when compared to other drive types (such as phillips or slotted).
Button Head Machine Screw
Button head machine screw have a wide range of uses, designed for light duty applications such as securing guards, covers, and ornamental fixtures. Most button head machine screws have no stamping or marking, which presents a pleasing appearance to an assembly.
Socket Shoulder Bolt
Socket shoulder bolts are very specialized. Sometimes called stripper bolts or just shoulder bolts, have a smooth shoulder that is larger than the thread diameter, running down the majority of the length of the fastener. The shoulder, having a larger diameter than the threads, allows the fastener to be used in rotating applications such as pulley shafts, bearing pins, axles, and pivot points. The thread length is standard for a given diameter. Unlike most fasteners, ASTM A574 socket head shoulder bolts are not sized by the thread diameter and length under the head, rather the diameter and length of the shoulder itself.
Socket Set Screw
Socket Set Screws are a headless fastener threaded its entire length (except for the point) used commonly for fastening mated parts such as a shaft and collar. These set screws are intended for compression applications only and are not customarily subjected to embrittlement tests. The ASTM F912 socket set screw's headless design allows the fastener to sit flush, or inset, into the threaded part.
Square Head Set Screw
Square head set screws, also known as jack bolts, are fully threaded fasteners with a square head and most commonly, a cup point, though other types of points are available. They have a large wrenching area that provides positive gripping for a hand wrench. They are ideal for holding pulleys, collars, and other machinery shafts where fine adjustments are necessary.
Socket Fastener Grades
Socket fasteners are available in either quenched and tempered alloy steel, or 18-8 stainless steel intended for use in applications requiring general corrosion resistance.
ASTM A574 Alloy Steel Socket Head Cap Screws & Socket Shoulder Bolts
ASTM A574 covers the requirements for quenched and tempered alloy steel hexagon socket head cap screws, 0.060 through 4.000 inches in diameter, where high strength is required.
ASTM F837 18-8 Stainless Steel Socket Head Cap Screws
Intended for use in applications requiring general corrosion resistance, ASTM F837 covers the chemical and mechanical requirements for stainless steel inch socket head cap screw, 0.060 through 1.500 inches in diameter.
ASTM F835 Alloy Steel Flat Head (Countersunk) Cap Screws & Button Head Machine Screws
Possessing material properties for high-strength conditions, ASTM F835 covers the requirements for quenched and tempered alloy steel flat head countersunk cap screws, 0.060 through 1.500 inches in diameter, and hexagon socket button head screws, 0.060 through 0.625 inches in diameter.
ASTM F879 18-8 Stainless Steel Flat Head (Countersunk) Cap Screws
ASTM F879 covers the chemical and mechanical requirements for stainless steel flat head countersunk cap screws with nominal thread 0.060 through 0.625 inches, intended for use in applications requiring general corrosion resistance.
ASTM F912 Alloy Steel Socket Set Screws
ASTM F912 covers the requirements for quenched and tempered alloy steel socket set screws in nominal diameters 0.060 through 2.000 inches, having Rockwell hardnesses from 45 to 53 HRC.
ASTM F880 18-8 Stainless Steel Socket Set Screws
Intended for use in applications requiring general corrosion resistance, ASTM F880 covers the requirements for austenitic grade stainless steel socket set screws sizes 0.060 through 1.000 inches in diameter.
Square Head Set Screws
Square head set screws are manufactured from alloy steel for maximum strength, as well as high resistance to galling, wear and fatigue.