Fastener screws can be classified into several categories based on their different characteristics and applications. Here are some common classifications:
- Classification by Material:
- Stainless steel screws: Possess good corrosion resistance and strength.
- Carbon steel screws: Common and cost-effective screws.
- Brass screws, copper screws, aluminum screws: These metal screws are often used in applications requiring good electrical conductivity or specific aesthetic requirements.
- Titanium alloy screws: High-strength, lightweight screws commonly used in high-end or special applications.
- Classification by Application:
- Wood screws: Used for connecting wood.
- Machine screws: Typically used with nuts for fastening metal or other materials.
- Self-tapping screws: Have the ability to cut their own threads into unthreaded holes.
- Fastener inserts, clamp screws, etc.: Fasteners with specific applications.
- Classification by Thread Type:
- M (Metric thread): A widely used thread standard.
- U (Rounded bottom thread), G (Pipe thread), RC (Internal pipe thread), BSP (Tapered pipe thread), etc.: These thread types are often used for specific applications or industry standards.
- Classification by Head Type:
- Round half head, round head, countersunk head, butterfly head, etc.: The choice of head type often depends on installation and aesthetic requirements.
- Classification by Usage Method:
- Machine screws: Used with mating internal threads.
- Self-tapping screws: Only have an external thread and can create their own threads in an unthreaded hole.
- Classification by Other Specific Uses or Designs:
- Slotted common screws: Commonly used for connecting small parts and components with different head styles available.
- Eye bolts: Used for lifting and transportation purposes.
- Set screws: Used to fix the relative position of components.
- Hex socket and hex socket with flower-shaped screws: Ideal for applications where space is limited or the screw head needs to be embedded.
- Locking bolts: Including square neck and tenon bolts, they are designed to prevent rotation.
In addition, fasteners screws can also be classified based on production standards such as American standard, international standard, Japanese standard, German standard, etc. These classifications help users choose the appropriate fastener screws according to specific needs.