Socket Screws

Socket screws, also known as hex socket head cap screws or Allen screws, are fasteners characterised by a cylindrical head with a recessed hexagonal drive. Designed for applications where space is limited or a clean, flush finish is required, these screws are tightened using an Allen key or hex driver. Their compact design allows for high torque transmission and secure fastening in machinery, construction, and precision engineering.

As a leading supplier in Singapore, RS Singapore offers an extensive range of high-quality socket screws sourced from trusted global brands. Our comprehensive selection includes metric and UNC (Unified National Coarse) thread options, multiple head styles such as cap, button, countersunk, and shoulder screws, and a wide variety of materials and finishes tailored to meet demanding project requirements.

When Would I Use a Socket Screw?

Socket screws, including popular types like the socket head cap screw and Allen head screw, are widely used across various industries and applications due to their compact design and high torque capability. They are especially valuable when traditional externally wrenched fasteners are impractical because of limited space.

Key reasons to choose socket screws include:

Space Constraints: Their internal hex drive allows tightening in confined or recessed areas where a conventional wrench cannot fit.
High Torque Transmission: The hexagonal socket provides excellent grip for applying strong torque without damaging the screw head.
Ease of Installation and Removal: Socket screws can be quickly installed or removed using a manual Allen key or hex wrench, as well as with powered tools equipped with Allen or hex bits.
Versatility: Commonly found in machinery assembly, industrial equipment, automotive manufacturing, and precision engineering.
Clean and Flush Fastening: Certain head styles, such as countersunk hex socket head cap screws, provide a neat, flush finish ideal for aesthetic or functional requirements.

Types of Socket Screws

Based on Head Shapes

You'll find various types of hexagon socket cap screw with distinct head shapes, including:

Hex Socket Button: With a smooth, rounded dome-shaped head, these screws offer a larger bearing surface and a more finished look. They are ideal for securing thin materials like sheet metal guards and often used where aesthetics or safety (reduced snagging) are important.
Hex Socket Cap: These socket cap screws feature a cylindrical head and deep hexagonal recess, these are the most widely used type. They provide high tensile strength and are suited for high-torque applications in confined spaces.
Hex Socket Countersunk: Designed for applications requiring the screw head to be level with or below the material surface for a flush finish.
Hex Socket Shoulder: Frequently used as a pivot or axis point due to their tightly toleranced shoulders and distinctive small cylindrical head with tall, vertical sides.

Based on Materials

Our socket screws are available in a range of materials to for various applications and environmental conditions:

Stainless Steel: Includes 316 and 304 grades, offering excellent corrosion resistance for demanding environments.
Steel: The most common choice, offering high strength and durability. Available in plain, black oxide, zinc-plated, or zinc-nickel plated finishes for enhanced corrosion resistance.
Brass: Offers good corrosion resistance and electrical conductivity, often used in electrical applications.
Titanium Alloy: Delivers exceptional strength-to-weight ratio and excellent corrosion resistance, ideal for high-performance applications.

Based on Thread Type and Size

Thread type and size refer to the form and dimensions of the screw's external threads, impacting compatibility with mating parts and the holding power achieved.

For example, metric threads are a standard in many industries, while UNC (Unified National Coarse) threads are common in others. Selecting the correct thread type and size is crucial for a secure and effective fastening in any application using a hex socket head cap screw or other socket screw types.

Industrial Applications of Socket Screws

Manufacturing

In manufacturing, socket head cap screws are vital for assembling machinery and equipment where strong, reliable fastening is required and space may be limited.

Hexagon socket cap screws are frequently used in machine tools, robotics, and automated systems due to their high torque capability and compact design. Furthermore, the use of socket screws in specific materials like stainless steel ensures durability in various production environments.

Construction

While not as prevalent as other fasteners, socket screws find applications in construction, particularly in prefabricated structures and architectural metalwork where a clean, recessed head is desired.

Hex socket countersunk screws are often used when a flush surface is necessary for aesthetic or functional reasons. The high strength of steel socket screws can also be advantageous in certain structural connections.

Maintenance, Repair, and Operations (MRO)

In MRO activities, a variety of Allen head screw types are essential for repairing and maintaining existing equipment and machinery.

Socket cap screws are commonly used for replacing worn or damaged fasteners, offering ease of installation and removal.

Automotive Manufacturing and Repair

Automotive manufacturing employs hexagon socket cap screws extensively in engine assembly, chassis construction, and interior fittings where strong, tamper-resistant fastening is needed.

Similarly, in automotive repair, mechanics rely on various sizes of socket head cap screws to replace original fasteners, ensuring the integrity and safety of vehicle systems. The availability of high-strength steel options is particularly important in this sector.

How to Choose the Right Socket Screw

Selecting the appropriate socket head cap screw will help to ensure the structural integrity and reliable performance of your assembly. When you buy a hexagon or socket head cap screw, consider these key factors:

Material Grade: Determines the socket head cap screw's strength and corrosion resistance; common options include alloy steel (various grades like 12.9, 10.9, 8.8), stainless steel (304, 316), and specialised alloys for demanding environments.
Diameter and Thread Pitch: The diameter specifies the nominal size of the screw, while the thread pitch (coarse or fine) affects the holding power and ease of installation; ensure compatibility with the tapped hole.
Length: Measured from under the head to the threaded end, the length must be sufficient to provide adequate thread engagement without bottoming out.
Head Style: While the cylindrical hex socket head cap screw is standard, variations like button head or flat head offer different aesthetic or functional characteristics.
Drive Type: The internal hexagon socket (Allen key) is standard, but other internal drives like spline or TORX® may be required for specific torque or tamper resistance needs.
Finish/Coating: Coatings such as zinc plating, black oxide, or passivation enhance corrosion resistance and can affect the screw's appearance and friction coefficient.
Application Requirements: Consider the specific demands of your application, including the load it will bear, the environment it will operate in (temperature, moisture, chemicals), and any relevant industry standards.

Buy Socket Head Cap Screws and More at RS Singapore

As a trusted supplier and distributor of mechanical fasteners and fixings in Singapore, RS Singapore offers a comprehensive selection of socket screws, including hexagon socket cap screws, Allen head screws, and more. We source our products from leading brands, such as Parker, Phoenix Contact, and our very own RS PRO, ensuring you receive products that meet stringent quality standards.

In addition to our extensive range of socket head cap screw options, you'll find other essential hardware, such as jubilee clamps and carriage screws, here. Explore our offerings online today to buy the fasteners you need and take advantage of our efficient delivery service. Check out our delivery information page to find out how our flexible options can work with your timeline.