As one of the common parts of Carriage bolts and conventional most common fasteners, also called half round head square neck bolt head square neck bolt, mushroom head or four step bolt, in English called Carriage bolts, or Mushroon head square neck bolts, from below the head (neck) has a four stage named as the main carriage screws. Its characteristics and functions is because the square neck fit in the square or round holes, so that the bolt will not move casually with nut to be fasteners can more closely united more force.
We used standard carriage screws into Chinese national standards, namely GB GB12, GB14 German standard, Carriage bolts, carriage bolts that German DIN603 standards of the United States, that is, ASME/ANSI made B18.5 carriage bolts, and of course Australia standard, namely the Olympic standard AS/NZS 1390 horse car bolts and French standard, the standard method NFE 27351 carriage Japanese standard bolts, carriage screws standard JIS B1171.
Carriage bolt is widely used in the general connection Ironwood through-hole mounting is not very convenient, less demanding, or car body, textile machinery, but also a large number of application and construction, machinery, logistics equipment, power equipment, bridge railings, wood and other industries. The carriage bolt installation use is applied to card slot or square cavity, usually used to connect two objects, through the light hole, and the nut (nut) with the use of single connection. The square neck (Square, neck) is stuck in the slot in the installation process, so that the bolt can be prevented from rotating, and the carriage bolts can be moved in parallel in the groove. Since the head of the carriage bolt is round, there is no cross groove or inner six corners, the design of the power assisted tool can also play a role of anti-theft in the actual connection process.

Of course, there are also non-standard pieces of the carriage bolt, also called shaped carriage bolts, mainly for short square neck, low square neck, short square neck, Gao Fangjing, small head, head type is different to the standard size of the site, according to the actual use of non standard screws carriage to custom, or use special shaped the difference of four party steps of larger carriage bolts.
Carriage bolt is widely used in the general connection Ironwood through-hole mounting is not very convenient, less demanding, or car body, textile machinery, but also a large number of application and construction, machinery, logistics equipment, power equipment, bridge railings, wood and other industries. The carriage bolt installation use is applied to card slot or square cavity, usually used to connect two objects, through the light hole, and the nut (nut) with the use of single connection. The square neck (Square, neck) is stuck in the slot in the installation process, so that the bolt can be prevented from rotating, and the carriage bolts can be moved in parallel in the groove. Since the head of the carriage bolt is round, there is no cross groove or inner six corners, the design of the power assisted tool can also play a role of anti-theft in the actual connection process.

On the production side, carriage bolt is different from other such as six angle bolts, inner six angle, flange bolts, carriage screws because the head and neck side of deformation, there is a huge demand for the power of machines, the first mock exam two red head machine production generally only, and the impact is relatively large that increase extended double car production, not suitable for small head machine multi station or new, so in the production speed is relatively slow, the yield is generally not high.
In the use of raw materials, but also different from other standard bolts, carriage bolts for large deformation, head and neck four materials are more common material that is easy to cause the head cracking, so raw materials carriage screws requirements are relatively high, steel grade 4.8 or grade 2 are Q195, 8.8 carbon steel grade 5 or at least 1035 35K, or non annealed 10B21 materials to production.

The most commonly used standard carriage bolts to the German IN603, as the metric unit is mm, the grade of the material is generally marked mostly 4.8 level and 8.8 level, many countries have adopted this standard, as one of the international standard carriage screws, metric Metric Standards of other countries are based on the DIN603 standard, carriage bolts according to the different size, cold heading specifications are M5, M6, M8, M10, M12, M16, and a large size such as M20 more difficult to fight, the general use of red red or red upsetting forging. The majority of products export or export parts to use, few domestic assembly.
Chinese general domestic use GB/T 12 or GB/T 14 carriage screws, is one of the most commonly used to China standard parts, mm mm, level is divided into 4.8, 8.8, 10.9, GB12 for small head carriage bolts, head diameter than the standard DIN603 and GB14, but the thickness ratio of the standard to thick, square neck edge and highly consistent with the DIN603 standard. The GB14 is equivalent to DIN603 Debiao, size difference, general general.


American carriage bolts standard for ASME/ANSI B18.5, divided into metric (mm or metric mm), inch (inch inches), grade and metric American Standard carriage screws are not the same, divided into grade 2 (equivalent to 4.8 Metric), grade 5 (equivalent to 8.8 grade male), Grade 8 (equivalent to 10.9 metric), and ASTM A307, the American carriage bolt fasteners are one of the most commonly used in Imperial units, and the size is similar to DIN603, the majority of countries in the use of units of inches, carriage screws for most common standards which is internationally recognized.
Non standard carriage bolts, English is also called Non-standard carriage bolt, is based on customer size or special needs to order the non-standard shaped bolts, according to the head shaped roughly divided into small head, head type carriage screws, according to the neck can be divided into short square neck, low square neck, Gao Fangjing, dwarf square neck bolts, of course, also can according to the needs of the head cross recessed or slotted, or in the rod diameter drilling thread, these are non-standard screws carriage, or special carriage bolts. Because there is no specific standard for reference, according to the general customer drawings and samples in addition to open mold customization.


Infly Fasteners factory is a professional production manufacturer of carriage bolts, carriage screws main production standards and special non-standard pieces of carriage bolts, provide standard GB12, German DIN603, ANSI B18.5 or ASTM A307 American Standard ANSI carriage bolts can be custom-made. Short square neck, short square neck, Gao Fangjing, low square neck and head type according to customer requirements, non-standard carriage bolt, small head according to the requirements, can be customized for clients head of cross slot, slotted, tail hole, rod diameter holes, cutting tail tail carriage screws of non-standard parts.

Production size: M6, M8, M10, M12, M16,  1/4, 5/16, 3/8, 1/2, 5/8, production of length 20-200mm.
We can provide the carriage bolt standard material grade 4.8, grade 5.6, grade 8.8, grade 2, grade 5, ASTM 307A.
Surface treatment for the light, color, blue white zinc plating, yellow zinc, color zinc, black zinc plating, blackening, hot galvanized, Dacromet etc.
When inquiry please provide carriage screws you need the size, quantity, grade, surface treatment, such as special requirements, please indicate in the inquiry, if you need to order non-standard carriage bolts, please provide a detailed description of the size, or drawings, or send the sample, we will give you a reply or the quotation in the first time, under normal circumstances, the price of our carriage bolts are tax ex factory price, please explain the special requirements.