2/8 fields identicalno sizes in common
ASME B18.2.1 vs DIN 933
ASME B18.2.1 and DIN 933 have no size designation in common: ASME B18.2.1 covers 1/4-20 to 1-8 and DIN 933 covers M4 – M24, and no size appears in both tables, so there is nothing to compare dimension by dimension. Substituting one for the other starts from matching nominal diameters, which the equivalence claim does not do for you.
Specification comparison
| Specification | ASME B18.2.1 | DIN 933 | Verdict |
|---|---|---|---|
| Standard body | ASME | DIN | differs |
| Title | Hex Head Cap Screw — Inch Series | Hexagon Head Screw / Bolt — Full Thread | differs |
| Fastener type | Hex head cap screw | Hexagon head bolt | differs |
| Head type | Hexagon head | Hexagon head | identical |
| Drive | External hex | External hexagon | differs |
| Size range | 1/4-20 to 1-8 | M4 – M24 | differs |
| Number of listed sizes | 8 | 12 | differs |
| Thread standard length defined | Yes | Yes | identical |
Dimension differences by sizecomputed from the tables in this database
| Size | Difference in this database |
|---|---|
| 1/4-20 | size not listed in the other standard |
| 5/16-18 | size not listed in the other standard |
| 3/8-16 | size not listed in the other standard |
| 1/2-13 | size not listed in the other standard |
| 5/8-11 | size not listed in the other standard |
| 3/4-10 | size not listed in the other standard |
| 7/8-9 | size not listed in the other standard |
| 1-8 | size not listed in the other standard |
Rows shaded amber differ between the two standards. Substitution should be checked against the affected sizes rather than assumed from the equivalence alone.