As an essential element in mechanical connections, the selection of fasteners' parameters is crucial for ensuring the stability and safety of the connection.
1. Product Name (Standard)
The fastener product name is directly associated with its structure and usage scenario. For fasteners that comply with specific standards, labeling the standard number can accurately reflect their design and performance. In the absence of clear standards, non-standard parts (non-standard parts) require detailed drawings to illustrate their dimensions and shapes.
2. Specifications
The specification of fasteners usually consists of two parts: the diameter of the thread and the length of the screw. The metric and American systems are the two main specification systems. Metric screws such as M4-0.7x8, where M4 represents a thread outer diameter of 4mm, 0.7 represents pitch, and 8 represents screw length. American screws such as 6 # -32 * 3/8, where 6 # represents the outer diameter of the thread, 32 represents the number of threads per inch of thread length, and 3/8 is the length of the screw.
3. Material
The material of fasteners determines their strength, corrosion resistance, and service life. Common materials include carbon steel, stainless steel, stainless iron, copper, aluminum, etc. Carbon steel can be subdivided into low carbon steel, medium carbon steel, high carbon steel, and alloy steel. It is crucial to choose the appropriate material based on the application scenario and performance requirements.
4. Strength level
For carbon steel fasteners, the strength grade reflects their tensile strength and yield strength. Common levels include 4.8, 5.8, 6.8, 8.8, 10.9, 12.9, etc. High strength screws, such as products of grade 8.8 or above, usually require quenching and tempering heat treatment to improve their mechanical properties.
5. Surface treatment
Surface treatment is mainly aimed at increasing the corrosion resistance and aesthetics of fasteners. Common processing methods include blackening, galvanizing (such as blue and white zinc, white zinc, etc.), copper plating, nickel plating, chrome plating, etc. Choosing the appropriate surface treatment method based on the usage environment and requirements can effectively extend the service life of fasteners.
In short, when selecting fasteners, it is necessary to comprehensively consider factors such as product name (standard), specifications, materials, strength grade, and surface treatment to ensure that they meet usage requirements and have good performance and lifespan.
Post time: Aug-28-2024