Value Collection 221055PR Shoulder Screw 3/8x5/8 Alloy Steel

Product Description

The VALUE COLLECTION 221055PR is a hex socket shoulder screw made from Grade 8 alloy steel in an uncoated finish. The shoulder measures 0.375 inches in diameter and 0.625 inches in length, with a 5/16-18 UNC threaded end for secure fastening. The hex socket drive requires a 3/16-inch hex key for installation. Head height is 0.250 inches, and head diameter ranges from 0.543 to 0.562 inches. This fastener is used in precision mechanical assemblies where a tight-tolerance cylindrical shoulder is needed to guide, pivot, or locate components. Machinists, maintenance technicians, and mechanical assemblers are the primary installers.

Shoulder screws of this type are commonly used in jigs, fixtures, dies, and machine tooling where a controlled-diameter bearing surface is required. The 5/16-18 UNC thread provides a standard coarse-thread engagement suitable for steel and aluminum tapped holes. The Grade 8 alloy steel construction supports high shear and tensile loads typical of industrial production and tooling environments. This screw suits both OEM assembly and field maintenance applications across general manufacturing and precision machining.

Key Features

• Shoulder diameter of 0.375 inches provides a precise bearing and locating surface
• Shoulder length of 0.625 inches accommodates standard tooling and fixture stack-ups
• Grade 8 alloy steel construction for high shear strength and durability
• 5/16-18 UNC thread standard for compatibility with common tapped holes
• 3/16-inch hex socket drive for installation with standard hex keys or Allen drivers
• Uncoated finish; meets ANSI B18.3, ASME/ANSI B18.3, and ASTM A574 standards

Compatibility

Designed as a standard shoulder screw for use in precision fixtures, jigs, dies, and mechanical assemblies requiring a 0.375-inch shoulder diameter and 5/16-18 UNC threaded engagement. Minimum order quantity is 25 pieces.

Installation Notes

Installation requires a 3/16-inch hex key or matching Allen driver. Ensure the mating tapped hole is clean and properly threaded to 5/16-18 UNC specification before driving the screw. Do not exceed the design shear load of the shoulder by overtightening the threaded section. De-energize and lock out any machinery before replacing shoulder screws in live equipment per applicable OSHA lockout/tagout procedures.