Fastener

Fastener Industry

• The United States fastener industry has 350 manufacturing plants and employs 40,000 workers.
• It is strongly tied to the production of automobiles, aircraft, appliances, agricultural machinery, commercial construction, and infrastructure.
• Over 200 billion fasteners are used per year in the U.S., with 26 billion used by the automotive industry.
• The Fastenal Company is the largest distributor of fasteners in North America.

Materials

• The three major steel fasteners used in industries are stainless steel, carbon steel, and alloy steel.
• Stainless steel fasteners are categorized into 200 series, 300 series, and 400 series.
• Titanium, aluminum, and various alloys are also common materials for metal fasteners.
• Coatings like zinc, chrome, and hot-dip galvanizing can be applied to improve performance characteristics.
• Specialized coatings or plating may enhance corrosion resistance.

Applications

• Factors to consider when selecting a fastener for industrial applications include threading, applied load, stiffness, and the number of fasteners needed.
• Specifics of the application, such as accessibility, environment, installation process, materials to be joined, reusability, and weight restrictions, should be taken into account.

Types

• Threaded fasteners have internal or external screw threads.
• Common types include screws, nuts, bolts, and washers.
• Other specialized types are captive threaded fasteners, studs, threaded inserts, and threaded rods.
• Multiple standards bodies exist for fasteners, including the US Industrial Fasteners Institute and the European Industrial Fastener Institute.

ASME B18 Standards and Military Hardware

• The American Society of Mechanical Engineers (ASME) publishes standards on fasteners.
• Examples of these standards include B18.3 for socket cap, shoulder, set screws, and hex keys (inch series) and B18.6.3 for machine screws, tapping screws, and metallic drive screws (inch series).
• B18.18 focuses on quality assurance for fasteners.
• B18.24 provides a part identifying number (PIN) code system standard for B18 fastener products.
• American fasteners historically did not fit British equipment properly, leading to the development of United States Military Standards and specifications.
• Traceability is a key component of most military standards, ensuring that materials and parts can be traced back to their source.
• Bar codes or similar methods are used to provide traceability in the supply chain.
• Traceability helps ensure the use of correct parts and adherence to quality standards.
• World War II played a significant role in the development of military standards for fasteners.

Fastener Data Sources