What is DIN 603 Carriage Bolt
The DIN 603 carriage bolt has a large round head with a square neck underneath, it is also known as the large round head square neck bolt. It is generally used in conjunction with a nut to securely fasten and connect 2 parts with holes.
When inserted into a slot, the square neck under the head of the carriage bolt fits into the slot of the connected piece, preventing the bolt from rotating in the same direction during installation and allowing for parallel movement within the slot.
Din 603 Carriage Bolts from AGICO
AGICO supplies DIN 603 carriage bolt in the material of a2, a4, which is also named sus304. Bolt grade 5.0, 7.0, 8.0, Common Dimensions: m5, m6, m8, m10, m12, m14, m16, m20.
DIN 603 Carriage Bolt Standard Specification:
| Nominal diameter d | M5 | M6 | M8 | M10 | M12 | M16 | M20 | |
| Pitch p | 0.8 | 1 | 1.25 | 1.5 | 1.75 | 2 | 2.5 | |
| b | L≤125 | 16 | 18 | 22 | 26 | 30 | 38 | 46 |
| 125≤L≤200 | 22 | 24 | 28 | 32 | 36 | 44 | 52 | |
| L>200 | / | / | 41 | 45 | 49 | 57 | 65 | |
| dk | max | 13.55 | 16.55 | 20.65 | 24.65 | 30.65 | 38.8 | 46.8 |
| min | 12.45 | 15.45 | 19.35 | 23.35 | 29.35 | 37.2 | 45.2 | |
| ds | max | 5 | 6 | 8 | 10 | 12 | 16 | 20 |
| min | 4.52 | 5.52 | 7.42 | 9.42 | 11.3 | 15.3 | 19.16 | |
| k | max | 3.3 | 3.88 | 4.88 | 5.38 | 6.95 | 8.95 | 11.05 |
| min | 2.7 | 3.12 | 4.12 | 4.62 | 6.05 | 8.05 | 9.95 | |
| s | max | 5.48 | 6.48 | 8.58 | 10.58 | 12.7 | 16.7 | 20.84 |
| min | 4.52 | 5.52 | 7.42 | 9.42 | 11.3 | 15.3 | 19.16 | |
| f | max | 4.1 | 4.6 | 5.6 | 6.6 | 8.75 | 12.9 | 15.9 |
| min | 2.9 | 3.4 | 4.4 | 5.4 | 7.25 | 11.1 | 14.1 | |
DIN 603 Carriage Bolt Standard:
The DIN 603 carriage bolt follows the German standard DIN603-1981, specifying metric thread sizes ranging from M5 to M20 and product grades as grade C carriage bolts.
Drawing of DIN 603 Carriage Bolt:
Marking Method for DIN603 Carriage Bolt
Example marking:
Thread specification d = M10, nominal length L = 60mm, uncoated round head square neck bolt marking:
Carriage Bolt DIN603-M10*60
Material and Mechanical Properties of DIN603 Carriage Bolt
DIN603 bolts are classified into carbon steel carriage bolts and stainless steel carriage bolts. The performance grades for carbon steel carriage bolts are 3.6 and 4.8. Standards can be referenced to GB3098.1, with chemical composition as shown below:
| Performance level | Material | chemical composition% | ||||
| C | P | S | B | |||
| min | max | max | max | max | ||
| 3.6 | carbon steel | – | 0.2 | 0.05 | 0.06 | 0.003 |
| 4.8 | – | 0.55 | 0.05 | 0.06 | 0.003 | |
3.6 and 4.8 grades permit the use of free-cutting steel, with maximum sulfur, phosphorus, and lead content of 0.34%, 0.11%, and 0.35%, respectively.
| Material | Performance level | Vickers hardness HV | Brinell hardness HB | Rockwell hardness HR | Nominal tensile strength | Minimum tensile strength | Yield point | guaranteed stress | Elongation after break | ||||
| min | max | min | max | min | max | Nominal | min | ||||||
| carbon steel | 3.6 | 95 | 220 | 90 | 209 | 52 | 95 | 300 | 330 | 180 | 190 | 180 | 25 |
| 4.8 | 130 | 220 | 124 | 209 | 71 | 95 | 400 | 420 | 320 | 340 | 310 | – | |
The material for DIN 603 stainless steel carriage bolts is SUS304. The material and chemical composition of stainless steel carriage bolts are:
| Use material | Chemical Composition% | ||||||||
| C | And | Mn | P | S | Cr | Mo | In | With | |
| SUS304 | 0.1 | 1 | 2 | 0.05 | 0.03 | 15-20 | – | 8-19 | 4 |
| Material | category | Group | Performance level | Thread diameter | tensile strength | Specify non-proportional elongation stress | Elongation after break |
| Stainless steel | austenite | A2、A4 | 50 | ≤M39 | 500 | 210 | 0.6d |
| 70 | ≤M24 | 700 | 450 | 0.4d | |||
| 80 | ≤M24 | 800 | 600 | 0.3d |
Application of DIN 603 Carriage Bolt
DIN 603 Carriage bolts are commonly used in dry-hanging marble installations. During tightening, the bolt shaft, due to the square neck, does not rotate, making it convenient for fixing and installation, primarily used in areas requiring countersunk screws.
Due to the round head design of the carriage bolt, without features like cross slots or hexagonal sockets for leverage tools, it also serves as an anti-theft measure during actual connection processes.
