Bolts with a diameter of 5-30 are generally formed by one-time cold pressing with a multifunctional cold heading machine, which has a fast production speed. Generally, heated round steel with a diameter of 20-60 is extruded by a friction press, and then trimmed, turned and wound. Many manufacturing steps and slow speed.
Extended data:
Stainless steel nut
Hexagon nut (GB6 170/DIN934), thin nut (GB6 172/DIN439), heavy nut (metric, American), nylon lock nut (DIN985-DIN982 thick type);
All-metal lock nut (DIN980M), cover nut (DIN 1587), hexagon nuts with flange (GB626 177/DIN6923), hexagon nuts with flange nylon lock nut (DIN6926), four-corner welding nut (DIN928) and hexagon welding nut (DIN929). Specification: M 1.6-M64
Alloy steel nut
Hexagon nuts (GB6 170/DIN934, GB6 175) and hexagon nuts with flange (GB6 177/DIN6923).
Round nut (GB8 12), small round nuts (GB8 10), American square nut, American hexagon nut (ANSI/ASME B 18.2.2), heavy nut (metric system, American system). Specification: 5/ 16-4 ".
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