Carriage bolts refer to round head square neck screws. According to the size of the head, carriage bolts are divided into large half round head carriage bolts (corresponding to standard GB/T14 and DIN603), and small half round head carriage bolts (corresponding to standard GB/T12-85). Carriage bolts , a type of fastener consisting of a head and a screw (a cylinder with external threads), which needs to be matched with a nut for the fastener to connect two parts with through holes.
Generally speaking, a bolt is used to connect two objects, usually through a light hole, and needs to be used in conjunction with a nut (nut). A single one does not work for connection, and the tool generally uses a wrench. The heads of carriage bolts are mostly hexagonal heads, etc., which are generally larger. The carriage bolt is applied in the groove, and the square neck is stuck in the groove during installation, which can prevent the bolt from rotating, and the carriage bolt can move in parallel in the groove.
Because the head of the carriage bolt is round, there is no design of available power tools such as cross recesses or inner hexagons, and it can also play a role in preventing theft during the actual connection process. Stainless steel carriage bolts are also called stainless steel round head square neck screws, which are made of 302 stainless steel. The use of 302 stainless steel is because the carriage screw has a large amount of deformation and requires a softer material. The annual ring-shaped concentric circles at the bottom of the head are specially designed for better extrusion deformation.