![High Strength Galvanized 2/5/8 Round Head Square Neck Carriage Coach Bolts ANSI/ASME B18.5](//www.micstatic.com/athena/img/transparent.png)
Round Head Square Neck Bolt / Carriage Bolt
A carriage bolt (also called coach bolt and round-head square-neck bolt) is a type of bolt. It is also known as a cup head bolt in Australia and New Zealand.
It is distinguished from other bolts by its shallow mushroom head and the fact that the cross-section of the shank, though circular for most of its length (as in other kinds of bolt), is square immediately beneath the head.[2] This makes the bolt self-locking when it is placed through a square hole in a metal strap. This allows the fastener to be installed with only one wrench, working from the opposite end. The head of a carriage bolt is usually a shallow dome. The shank has no threads and its diameter equals the size of the square cross-section.
The carriage bolt was devised for use through an iron strengthening plate on either side of a wooden beam, the squared part of the bolt fitting into a square hole in the ironwork. It is common to use a carriage bolt on bare timber, the square section giving enough grip to prevent rotation.
Standard |
ANSI/ASME B18.5/DIN603 |
Strength Grade |
Gr 2/5/8; Gr 4.8/8.8/10.9; A2-70, A4-70 |
Material |
Q195/35K/10B21/40CR/Stainless Steel 304/316 |
Size |
Dia 1/4''-1'', M5-M20, or customized |
Exterior Finish |
Plain/Zinc/Black/Decromet |
Package |
Cartons + pallets, or customized |
![High Strength Galvanized 2/5/8 Round Head Square Neck Carriage Coach Bolts ANSI/ASME B18.5](//www.micstatic.com/athena/img/transparent.png)
DIN 603
Thread d |
M5 |
M6 |
M8 |
M10 |
M12 |
M16 |
M20 |
P |
0,8 |
1 |
1,25 |
1,5 |
1,75 |
2 |
2,5 |
b |
l < 125mm |
16 |
18 |
22 |
26 |
30 |
38 |
46 |
125 < l < 200mm |
22 |
24 |
28 |
32 |
36 |
44 |
52 |
l > 200mm |
- |
- |
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 |
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 |
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 |
r1 |
approx. |
10,7 |
12,6 |
16 |
19,2 |
24,1 |
29,3 |
33,9 |
r2 |
max. |
0,5 |
0,5 |
0,5 |
0,5 |
1 |
1 |
1 |
r3 |
max. |
0,75 |
0,9 |
1,2 |
1,5 |
1,8 |
2,4 |
3 |
v |
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 |
ASME B18.5
Nominal Size or Basic Diameter |
E |
A |
H |
J |
T |
U |
Body Diameter |
Head Diameter |
Head Height |
Slot Width |
Slot Depth |
Fillet Radius |
Max |
Min |
Max |
Min |
Max |
Min |
Max |
Min |
Max |
Min |
Max |
Min |
1/4'' |
0.2500 |
0.2500 |
0.2450 |
0.4370 |
0.4180 |
0.1910 |
0.1750 |
0.0750 |
0.0640 |
0.1170 |
0.0970 |
0.0310 |
0.0160 |
5/16'' |
0.3125 |
0.3125 |
0.3070 |
0.5620 |
0.5400 |
0.2450 |
0.2260 |
0.0840 |
0.0720 |
0.1510 |
0.1260 |
0.0310 |
0.0160 |
3/8'' |
0.3750 |
0.3750 |
0.3690 |
0.6250 |
0.6030 |
0.2730 |
0.2520 |
0.0940 |
0.0810 |
0.1680 |
0.1380 |
0.0310 |
0.0160 |
7/16'' |
0.4375 |
0.4375 |
0.4310 |
0.7500 |
0.7250 |
0.3280 |
0.3020 |
0.0940 |
0.0810 |
0.2020 |
0.1670 |
0.0470 |
0.0160 |
1/2'' |
0.5000 |
0.5000 |
0.4930 |
0.8120 |
0.7860 |
0.3540 |
0.3270 |
0.1060 |
0.0910 |
0.2180 |
0.1780 |
0.0470 |
0.0160 |
9/16'' |
0.5625 |
0.5625 |
0.5550 |
0.9370 |
0.9090 |
0.4090 |
0.3780 |
0.1180 |
0.1020 |
0.2520 |
0.2070 |
0.0470 |
0.0160 |
5/8'' |
0.6250 |
0.6250 |
0.6170 |
1.0000 |
0.9700 |
0.4370 |
0.4050 |
0.1330 |
0.1160 |
0.2700 |
0.2200 |
0.0620 |
0.0310 |
3/4'' |
0.7500 |
0.7500 |
0.7420 |
1.2500 |
1.2150 |
0.5460 |
0.5070 |
0.1490 |
0.1310 |
0.3380 |
0.2780 |
0.0620 |
0.0310 |
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