Understanding Socket Head Screw Dimensions: 3/8-Inch Diameter Explained

Socket head cap screws, also known as socket caps, socket heads, or socket screws, are a type of threaded fastener with sockets in their heads through which torque is applied to screw the fastener. The dimensions of a 3/8-16 flat-head socket cap screw, for example, are detailed by several retailers. These screws are typically made of stainless steel and are suitable for projects requiring the screw to sit flush with the material.

Socket head cap screw dimensions

Socket head cap screws are a type of threaded fastener with sockets in their heads through which torque is applied to screw the fastener. The most common uses of socket head cap screws include heavy machinery, industrial equipment, automotive assemblies, and structural projects.

Socket head cap screws come in a variety of dimensions. The dimensions of a 3/8-16 flat-head socket cap screw, for example, are as follows: a grip range of 0.562-0.625 inches, a blind-side protrusion of 0.015 inches, a rivet shank diameter of 0.1875 inches, and 16 threads per inch.

The dimensions of a 3/8-inch socket head cap screw are as follows: a screw length of 3/8 inch, a hexagon socket size of 5/16 inch, and a hexagon width of 0.062-0.125 inches.

The dimensions of a socket head cap screw can vary depending on the specific type and size of the screw, including the basic screw diameter, head height, and thread length.

When selecting a socket head cap screw, it is important to consider the intended application and choose a screw with appropriate dimensions and specifications to ensure optimal performance and safety.

Flat-head socket cap screw dimensions

Flat-head socket cap screws are used in situations where the available space doesn’t allow for using a wrench or a socket. They are designed to sit flush with the material you are using them on. Flat-head socket cap screws are available in a variety of sizes and materials, including stainless steel.

Another example is the 3/8-16 Flat Head Socket Cap Screw by Fastenere, which is available in lengths from 5/8" to 2-1/2". The grip range decimal min and max are 0.4375 and 0.6562, respectively. The blind side protrusion is 0.0625, and the rivet shank diameter is 0.25. The threads per inch (TPI) are 16 for this particular screw.

Flat-head socket cap screws typically have a hexagonal recess and require a specific tool, such as an Allen wrench or a screwdriver, for fastening. The dimensions of the flat-head socket cap screw are important to ensure the correct tool is used and that the screw sits flush with the material.

Button head socket cap screw dimensions

Button head socket cap screws are used in high-strength assemblies that require a finely tooled appearance. The rounded "Button" head has a broader bearing surface than a standard Socket Head Cap Screw, allowing for solid seating on the mating material. They are available in stainless steel, black oxide, or zinc-baked platings.

The button head design offers a low-profile head and a larger bearing surface, making them ideal for demanding applications like automotive, industrial, and heavy-duty projects. The low-profile button head provides a smooth, rounded finish, while the Thermal Black Oxide coating adds a mild layer of corrosion resistance, making these screws perfect for indoor use and light outdoor applications.

Button head socket cap screws are easily installed using a hex socket wrench or Allen wrench, which is why they are also commonly referred to as Allen button head bolts. Their tall, uniformly domed profile allows for excellent driver engagement.

Between their alloy composition and heat treatment, these socket screws have a tensile and yield strength comparable to that of the next larger diameter of a common, low carbon steel, round head machine screw. As a result, fewer screws may be needed in a particular design to achieve specific clamp loads, meaning lighter assemblies and reduced costs.

Low head socket cap screw dimensions

Low-head socket cap screws are used in low screw head height applications. This means they are only suitable for low-strength applications. They are commonly used in the designing of metal shears, which require a very low head length, and in home furniture assembly, where their low height and clean appearance are desirable.

Low-head socket cap screws are available in stainless steel, carbon steel, or alloy steel, which means they can resist corrosion and be used in underwater applications. They also provide maximum fatigue control due to the tightly controlled fillet between the head and body.

The dimensional standards for low-head socket cap screws are as follows:

• DIN 7984: Low Head Socket Cap Screws with shank lengths ls and lg
• DIN 6912 - Cap Screws Thin Cylindrical Head above 125mm up to 200mm
• ASME B18.3- Low Head Socket Head Cap Screw with a nominal size (basic screw diameter) and maximum chamfer or radius

ITA Fasteners is one supplier of low-head socket cap screws and they stock several dimensions depending on individual requirements. They also undertake custom orders of varying sizes.

Socket shoulder screw dimensions

Socket shoulder screws, also known as stripper bolts, are a type of socket cap screw that is only partially threaded, with a shoulder. These bolts are used on machinery to provide a smooth surface for bearings to ride on. They are measured by their diameter of shoulder x length of shoulder x thread diameter.

The dimensions of a socket shoulder screw can vary depending on the specific application and requirements. For example, the Bolt and Nut Australia website offers socket shoulder screws in the following dimensions:

• 6mm Shoulder (M5 x 0.80p Metric Coarse Thread)
• 8mm Shoulder (M6 x 1.00p Metric Coarse Thread)
• 10mm Shoulder (M8 x 1.25p Metric Coarse Thread)
• 12mm Shoulder (M10 x 1.50p Metric Coarse Thread)
• 16mm Shoulder (M12 x 1.75p Metric Coarse Thread)
• 20mm Shoulder (M16 x 2.00p Metric Coarse Thread)
• 1/4" Shoulder (#10 x 24" TPI UNC Coarse Thread)
• 5/16" Shoulder (1/4" x 20 TPI UNC Coarse Thread)
• 3/8" Shoulder (5/16" x 18 TPI UNC Coarse Thread)

Additionally, United Fasteners offers shoulder socket cap screws in metric and imperial sizes. The metric sizes range from M5 to M20 in diameter and 10mm to 150mm in length, while the imperial sizes range from #10-24 to 5/8" in diameter and 1/4" to 6" in length.

It is important to note that the dimensions of socket shoulder screws can vary slightly between different manufacturers and batches. Therefore, it is always a good idea to refer to the specific product specifications provided by the manufacturer when selecting a socket shoulder screw for a particular application.

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