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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 |
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 |
BOLTS | SCREWS | NUTS | WASHERS |
CARRIAGE BOLT | SHOULDER BOLT | HEX HEAD BOLT | FLANGE BOLT |
1. Bolts: hex head bolts, hex socket bolts, carriage bolts, flange bolts, etc
2. Screws: machine screws, self-drilling screws, set screws, 12.9 shoulder screws, hex head wood screws, self-tapping screws, etc
3. Nuts: hex nuts, k-nuts/k-lock nuts, nylon inserted nuts, stamped metal self-locking nuts, hex flange nuts, cap nuts, rivet nuts, etc
4.Non-standard fasteners: semi-hollow rivets, step rivets, etc
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