Screw shopping mall---one-stop service
Language
Screw shopping mall---one-stop service
1. Thread Size and Pitch
Thread Size (Diameter): The nut must have the same thread size as the bolt. Thread size is typically measured in metric (e.g., M6, M8) or imperial (e.g., 1/4”, 1/2”) units.
Thread Pitch: Thread pitch refers to the distance between threads on the bolt and nut. In metric threads, this is measured in millimeters per thread, and in imperial threads, it's measured in threads per inch (TPI). The nut must match the bolt’s thread pitch exactly.
2. Material Compatibility
Same Material: Ideally, the nut should be made from the same material as the bolt to ensure consistent strength, corrosion resistance, and thermal expansion. For example, use stainless steel nuts with stainless steel bolts.
Corrosion Resistance: In corrosive environments, such as marine or chemical industries, choose nuts made from corrosion-resistant materials like stainless steel, brass, or coated steel to match the bolt.
Electrochemical Compatibility: In environments prone to galvanic corrosion, avoid using nuts and bolts made from dissimilar metals that can cause corrosion when in contact.
3. Strength Grade
Matching Strength: The strength grade of the nut should match or exceed the strength grade of the bolt. Strength grades are indicated by numbers on metric fasteners (e.g., 8.8, 10.9) or by markings on imperial fasteners.
High-Strength Applications: For high-stress or load-bearing applications, ensure that the nut is rated for the required load. For example, use Grade 8 nuts with Grade 8 bolts.
4. Nut Type
Hex Nuts: The most common type, used in general applications. They are available in standard (full) height and thinner (jam) versions.
Lock Nuts: Designed to prevent loosening due to vibration or dynamic loads. Types include nylon insert lock nuts, all-metal lock nuts, and prevailing torque nuts.
Flange Nuts: Have a built-in washer to distribute the load over a larger area, preventing damage to the surface and reducing the need for a separate washer.
Wing Nuts: Feature “wings” for easy hand-tightening, suitable for applications where frequent adjustment or removal is required.
Cap Nuts: Have a closed end to protect the exposed bolt threads and provide a finished appearance.
5. Coatings and Finishes
Zinc-Plated: Provides basic corrosion resistance and is suitable for indoor applications.
Galvanized: Offers superior corrosion resistance for outdoor or marine environments.
Black Oxide: Provides a decorative finish and mild corrosion resistance, commonly used in automotive and machinery applications.
Passivation: A process applied to stainless steel nuts to enhance their corrosion resistance by removing surface contaminants.
6. Environmental Considerations
Temperature: For high-temperature applications, choose nuts made from materials like stainless steel, titanium, or high-temperature alloys.
Chemical Exposure: In environments with exposure to chemicals, acids, or salts, select nuts that are resistant to chemical corrosion, such as those made from stainless steel or special alloys.
7. Application-Specific Considerations
Shear and Tension: Consider the load the bolt-nut assembly will bear. For shear loads, standard nuts may suffice, but for tension loads, high-strength nuts or lock nuts might be required.
Accessibility: In situations where space is limited or access is difficult, consider using nuts that can be easily installed or removed, such as wing nuts or nuts with a built-in flange.
8. Standards Compliance
International Standards: Ensure that both the nut and bolt comply with relevant standards (e.g., ISO, DIN, ANSI) to ensure compatibility and performance.
Industry-Specific Standards: In some industries, such as automotive or aerospace, specific standards dictate the type of nuts and bolts to be used. Always check for compliance with these standards.
9. Torque Requirements
Torque Values: The torque required to secure the nut on the bolt should be within the recommended range for both the bolt and nut to avoid over-tightening or under-tightening.
Lubrication: If using lubricated bolts or nuts, consider the reduced friction when determining torque settings, as lubrication can significantly reduce the required torque.
Conclusion
When choosing nuts according to bolts, it’s essential to match the thread size, material, strength grade, and type. Environmental conditions and specific application requirements also play a crucial role in selecting the appropriate nut. By carefully considering these factors, you can ensure a secure and durable fastening solution.
Wuxi Zhuocheng Mechanical Components Co., Ltd. is established in 1990, and one group of manufacturing and selling professional fastener
Copyright © 2021 Wuxi Zhuocheng Mechanical Components Co.,Ltd. - All Rights Reserved.
