ASTM A574 High-Strength Socket Head Cap Screws (Inch) Specification

Applications & Industries

What High-Strength Socket Head Cap Screws are specified for, industry by industry.

Industries that specify High-Strength Socket Head Cap Screws

• Machine building & OEM The default fastener on production equipment: covers, brackets, motor mounts and sub-assemblies tightened to a specified torque.
• Automotive & transport Chassis, driveline and body fixings that see vibration and are assembled to a controlled preload.
• Steel fabrication Bolted connections in frames, enclosures, walkways and weldments, on the bench and on site.
• Energy & infrastructure Tower, pipework, switchgear and plant fixings specified for long service life and inspectable joints.
• Maintenance & MRO Stocked replacements matched to an existing property class, thread and finish.
• Food, pharma & cleanroom Stainless assemblies that are washed down, where the finish matters as much as the strength.

Typical applications

• assemblies that are dismantled for service and re-torqued
• joints where the property class is stated on the drawing
• clamping two machined faces to a calculated preload
• bolting brackets, motors and gearboxes to a frame

Service conditions to specify against

Marine and coastal

Available in A4 (316) stainless for chloride exposure — coastal structures, pool halls, water treatment and deck hardware, where A2 will eventually pit.

High load

Supplied in ISO 898-1 property classes, so the joint can be designed to a stated proof load and tightened to a calculated torque rather than by feel.

Torque and preload

The joint is designed around bolt tension, so lubrication, coating and the friction coefficient all change the torque figure — state them together.

Where to use something else

• Do not use a machine thread into unthreaded sheet or timber; use a tapping screw, rivet nut or insert made for that parent material.

Need help matching High-Strength Socket Head Cap Screws to your application? Send the assembly, the load and the environment with your enquiry and we will specify the size, material and finish against them.