FLAT HEAD CAP SCREW
This fastener is a quality, close tolerance product with dimensions conforming to USASI B18.6.2. Made of Grade 2 steel, it provides a tensile strength of 74,000 psi. The flat countersunk head has an accurately milled slot for holding or tightening with screwdriver. Available from stock in diameters from 1/2 through 3/4 inches; lengths from 1 through 3 inches. Coarse threads. Note: length of flat head cap screws is measured from the largest diameter of the bearing surface of the head to the extreme point, in a line parallel to the axis of the screw.
GRADE 2 HEX CAP SCREW
Most commonly used type, made to meet SAE Grade 2 specifications, and offering tensile-strength of 74,000 psi to 60,000 psi depending on size. Used in tapped hole, or with nut. Available from stock in diameters from 1/4 inch to 2 inches; lengths from 1/2 inch to 8 inches. Bright finish is standard; also finished to specification, in zinc or cadmium plate; phosphate coated; galvanized. Copper, nickel, chromium plated on a special basis. Threads are UNC-2A and UNF-2A to a standard length of twice the diameter plus 1/4 inch for screws through 6 inches long; plus 1/2 inch for screws over 6 inches. Other materials in production runs.
Large, flattened thin head requires minimum clearance and provides for an unobstructed surface in yielding materials such as wood, leather, rubber belting etc. UNC-2A threads. Sizes: 1/4, 5/16, 3/8-inch diameters; 3/4 through 3- inch lengths.
GRADE 5 HEX CAP SCREW
High strength heat treated fastener with tensile strength of 120,000 psi to 105,000 psi depending on size. Identified by 3 radial dashes on head. Used in tapped hole or with nut. Stocked in diameters from 1/4 inch to 1 inch; lengths from 1/2 inch to 12 inches. UNC-2A and UNF- 2A threads. Black finish; other finishes to specification as above. High strength of this product provides stronger joints that stay tight when torqued to recommended pre-load.
GRADE 8 HEX CAP SCREW
High strength, heat treated alloy fastener offering tensile strength of 150,000 psi. Identified by six radial dashes on head. Black finish; other finishes to specification. UNC-2A and UNF-2A threads. Diameters from 1/4 inch to 1-1/2 inch; lengths from 1/2 inch to 8 inches.
A325 HEAVY HEX STRUCTURAL BOLT
Has tensile strength of 120,000 psi to 105,000 psi depending on size. Conforms to ASTM A325 specification for structural steel fasteners. Head is larger across the flats than the Hex Cap Screw dimensions. Permits washers to be eliminated and same size wrench for nut and bolt. Has shorter thread length, too, to exclude threads from shear planes in structural joints. Black finish; available galvanized to order. Developed for use in steel frame buildings, bridges, large equipment. Diameters from 5/8 inch to 1-1/4 inch; lengths from 1-1/2 inch to 8-1/2 inches. Coarse thread only.