What is a Screw?
A screw is a type of fastener with external threads, designed to be inserted directly into a pre-tapped hole or material by rotating itself. It typically does not require a nut and is commonly used for direct fastening in materials such as metal, plastic, or wood. Screws include types like self-tapping screws and machine screws, and they are widely applicable in both pre-drilled and non-drilled joining scenarios.
What is a Bolt?
A bolt is a fastener used in conjunction with a nut or tapped hole. It features a uniform cylindrical body with a flat or slightly chamfered end. Bolts are generally inserted through aligned holes in parts and clamped by tightening a nut, providing high-strength fastening. They are essential components in industrial assemblies requiring reliable structural connection.
Key Differences Between Screws and Bolts
Connection Method:
Screws are usually driven directly into a component, relying on the thread’s frictional force to secure. Bolts require a nut or a tapped hole, offering clamping force from both ends of the assembly.
End Shape:
Screws typically have pointed or tapered ends for self-piercing or self-tapping into material. Bolts usually have flat ends, ideal for insertion into pre-drilled holes and securing with nuts.
Usage Scenario:
Screws are ideal for light-duty connections, soft materials, or assemblies that may need frequent disassembly. Bolts are better suited for high-load connections in structural or heavy-duty applications.
Nut Requirement:
Screws generally do not need nuts, whereas bolts nearly always require a nut or an internally threaded component for secure fastening.
Common Types of Screws
Phillips head screws, socket screws, self-tapping screws, self-drilling screws, machine screws, stud screws, countersunk screws, round head screws, flat head screws, pan head screws, hex head screws, plastic anchor screws, washer-integrated screws, and specially shaped screws.
Source: https://blog.thepipingmart.com/other/what-are-the-various-screw-types-and-their-applications/
Common Types of Bolts
Hex bolts, heavy hex bolts, flange bolts, T-bolts, anchor bolts, expansion bolts, U-bolts, eye bolts, square head bolts, socket head bolts, fully threaded bolts, partially threaded bolts, stud bolts, slotted bolts, shear bolts, step bolts, anti-theft bolts, combination bolts, and custom-shaped bolts.
Application Differences
Screws:
Used in household appliances, electronics, lightweight machinery, woodworking, and other low-load fastening tasks.
Bolts:
Widely used in structural steel assemblies, bridges, industrial machinery, piping systems, wind turbines, and heavy-duty connections.
Common Fastener Materials for Screws and Bolts
- Carbon Steel: Economical with good strength; suitable for general structural use.
- Stainless Steel (304/316): Corrosion-resistant, ideal for food, chemical, and medical industries.
- Duplex Stainless Steel: Combines austenitic and ferritic structures for both strength and corrosion resistance.
- Monel (Nickel-Copper Alloy): Excellent in marine and chemical environments.
- Hastelloy: Superior resistance to strong acids and alkalis.
- Inconel: High-temperature resistant nickel alloy.
- Incoloy: Suitable for acidic and high-temperature environments.
- Nickel Alloy: Offers excellent corrosion, thermal, and electrical properties for chemical and electronics industries.
Contact MT.BOLTS
MT.BOLTS specializes in the manufacturing and supply of industrial fasteners including screws, bolts, nuts, and washers. Our products conform to international standards (ANSI / ASTM / DIN / ISO / JIS) and are available in various materials, dimensions, and surface finishes.
Contact us today to learn more about fasteners and to procure high-quality products. Our technical team is ready to provide expert support and custom selection solutions.
