Flat Washer

Federal Supply Class (FSC) 5310 encompasses various nuts and washers, including flat washers. These washers are essential components used in many applications to distribute load evenly, prevent damage to mating surfaces, and provide isolation.

Here's an overview of flat washers included in FSC 5310:

Function:

• Distribute load evenly across a larger surface area, preventing concentrated pressure that could damage the mating surfaces.
• Act as a spacer, providing a gap between the screw head or nut and the surface to prevent binding or galvanic corrosion.
• Isolate the screw or nut from the surface, preventing electrical conductivity or chemical reactions.

Types:

• Plain flat washers: The most common type, featuring a flat surface and a central hole. They come in various sizes and thicknesses depending on the application.

• Fender washers: Similar to plain flat washers but with a larger outside diameter that provides additional bearing surface.

• Tapered flat washers: Have a slightly conical shape, which helps to compensate for uneven surfaces and ensure proper alignment.

• Tooth lock washers: Feature small teeth on their inner diameter that bite into the mating surface to prevent the nut or screw from loosening.

• Split lock washers: Have a split through the middle that creates spring tension, ensuring a tight grip on the screw or nut.

• Countersunk flat washers: Have a tapered edge that fits into a countersunk hole, providing a flush surface.

Materials:

Flat washers are typically made from various materials, including:

• Steel: The most common material, offering good strength and durability.
• Stainless steel: Resistant to corrosion, making it suitable for applications where moisture or chemicals are present.
• Aluminum: Lightweight and corrosion-resistant, ideal for applications requiring weight reduction.
• Brass: Offers good electrical conductivity and is resistant to corrosion, making it suitable for electrical applications.
• Nylon: Provides good insulation and is resistant to chemicals, making it suitable for certain industrial applications.

Applications:

Flat washers are used in various applications, including:

• Machinery and equipment assembly
• Electrical and electronic equipment
• Automotive and aerospace industries
• Construction and building projects
• Plumbing and HVAC systems
• Furniture assembly

Standards:

Flat washers are manufactured according to various standards, including:

• ANSI/ASME B18.21.1: American National Standard for Flat Washers
• ISO 7089: International Organization for Standardization standard for Flat Washers
• DIN 125: German Institute for Standardization standard for Flat Washers
• BS 4320: British Standards Institution standard for Flat Washers

Procurement:

Flat washers are widely available from various suppliers and distributors of nuts and bolts. They can also be purchased online from various retailers. When purchasing flat washers, it is important to specify the correct size, thickness, material, and finish to ensure they meet your specific needs.

Additional Resources:

• American National Standards Institute (ANSI): https://ansi.org/
• International Organization for Standardization (ISO): https://www.iso.org/home.html
• German Institute for Standardization (DIN): https://www.din.de/de
• British Standards Institution (BSI): https://www.bsigroup.com/