What are the standards and common sense of hand tightening screws

According to everyone's feedback, many people care about the standard of hand tightening screws. As a screw product that is not very simple to process, the use of this screw product is common knowledge of manufacturing industry, and its role is huge. Hand tightening screw standards need to consult with the merchant before purchase, to understand this nut product in a deeper level. Through the following content, we have a comprehensive understanding of the standard and common sense of hand tightening screws.

Hand tightening screw standard

Hand tightening screw standard:

Main standard and technical parameters

1. Nominal diameter: recognized diameter of screw design, production, inspection, etc.

2. Pitch or number of teeth: the distance between two adjacent crests or the number of teeth per inch.

3. Round diameter: The maximum average outer diameter measured by the screw.

4. Triangle diameter: The average distance from the top of the screw triangle to the opposite arc.

5. Bottom aperture: the original aperture before the tapping of the screw hole.

6, nominal length: screw design, production, inspection and other recognized length.

7. Destructive Torque: The minimum torque required for the screw to reach a twisted or twisted state.

8. Tension resistance: The minimum tensile force required for the screw to produce plastic deformation or fracture in the axial direction.

9. Surface hardness: The average hardness measured on the flat surface of the screw surface.

10. Core hardness: The average hardness measured by the screw section from the center of about 1/2 radius.

11. Carburized hardened layer depth: the thickness of the hardened layer after the surface of the screw is carburized.

Hand tightening screw specifications

The standard of the screw is generally on the market: DIN912 (GB70-85) hexagon socket head cap screws,

Its smallest size can be reached to M2 (the diameter of the threaded rod, the length of the thread is not limited), for example: M2.5 M3 M4 M5 M6 M8 M10 M12 M14, etc. (the length is not limited) Yes, I am following You said that the specification of the screw is what the oil consists of: it consists of the length of the threaded rod of the screw (excluding the head), the thread (the distance between the thread and the thread) and the diameter of the threaded rod. I take the above data for an analogy. For example: the smallest M2, its professional standard is: M2-0.4X5 (M2 is the length of the threaded rod, 0.4 is the thread pitch, 5 is the diameter of the threaded rod). Generally, their materials are: 4.8, 8.8, 10.9, 12.9, etc. There are also stainless steel, S04 S16 and so on.

The hand tightening screw standard is very popular, and it allows most people to reduce the difficulty of many repairs. The merchant should inform the purchaser of the effective information and understand the precautions. Therefore, the knowledge of metal screw products should be well known to us. When using this screw product, it can be done independently, and vice versa. Through the above, I believe that everyone has a preliminary grasp of the standard of hand tightening screws.