Understand The Standards And Dimensions Of External Hexagonal Bolts

In our daily lives, the outer hexagonal bolt is a very common industrial bolt. When decorating, we often use external hexagonal bolts. If we understand the standards and sizes of external hexagonal bolts, it will make it easier for us to choose bolts that are suitable for our needs.

Standard for external hexagonal bolts
The national standard GB/T5782-86 specifies the thread specifications for external hexagonal bolts: the thread specifications are M3~M64, grade A and B hexagonal head bolts. Among them, Class A is suitable for bolts with D<=24 and L<=10D or L<=150mm (whichever is smaller); B-grade is suitable for bolts with D>24 or L>10D or L>150 (whichever is smaller).
Dimensions of external hexagonal bolts
The standard for external hexagonal bolts includes DIN, ANSI, BS, and GB, and stainless steel or carbon steel can be selected as the material. The diameter is 5mm~20mm, 1/4 "~3/4", the length is 8mm~200mm, and 5/16 "~8". Thread specifications include metric, coarse, fine, and imperial. There are mechanical performance levels of 4.8, 5.8, 6.8, 8.8, 9.8, 10.9, and 12.9. Surface treatment options include natural color, galvanizing, blackening, and nickel plating.
In addition, the head size may vary depending on the specifications of the outer hex bolts. Specifically, as follows:
Size standard M6 M8 M10 M12 M14 M16 M18 M20 M22 M24 M27 M30
Opposite side S GB30 10 14 17 19 22 24 27 30 32 36 41 46
GB1228 21 27 34 36 41 46 50
GB5782/5783 10 13 16 18 21 24 27 30 34 36 41 46
DIN931/933 10 13 17 19 22 24 27 30 32 36 41 46
Thickness K GB30 4 5.5 7 8 9 10 12 13 14 15 17 19
GB1228 7.5 10 12.5 14 15 17 18.7
GB5782/5783 4 5.3 6.4 7.5 8.8 10 11.5 12.5 14 15 17 18.7
DIN931/933 4 5.3 6.4 7.5 8.8 10 11.5 12.5 14 15 17 18.4
It should be noted that:
1. GB5782 refers to half teeth; GB5783 refers to full teeth, with the same technical dimensions for the head;
2. DIN931 refers to half teeth; DIN933 refers to full teeth, with the same technical dimensions for the head;
GB1228 is a large hexagonal head bolt used for steel structures;
GB30, commonly known as the old national standard; GB5782/5783 is commonly known as the new national standard.
Overall, the standards and sizes of external hexagonal bolts are very diverse, with many different options to meet different occasions and requirements. Understanding the specifications and dimensions can help us better choose the external hexagonal bolts that are suitable for our needs.