Hollow bolts are usually used in clothing, shoes and other fields. The solid core must be riveted again to connect heavy products and workpieces. They are usually not detachable. Half space center bolts are more commonly used. Bundle mouth (small end of cable diameter) nails are manufactured with hard cables. They can pass through thick steel plate within 0.5mm without pre hole. Bolts can not be bent and deformed. Therefore, they are widely used in the industry The hollow rivet (half space center bolt) on the upper edge of trunk, trunk and military luggage leather goods shall be manufactured by copper wire. Generally speaking, it is stipulated that it can not be split after riveting. There are many types. At this stage, it has just begun to replace the shaft on the top of some small toys with large cap aluminum iron rivets, which can greatly reduce the product cost. Core pulling and core striking bolts are usually used for riveting of thin and soft raw materials, and the general regulations are not strict. The materials for production and manufacturing are generally made of raw materials with good plastic deformation. All aluminum double drum rivets are used for the key of semicircular head bolts, which are widely used in riveting places with large transverse loads. Because of its thick head and corrosion resistance, the flat cone head bolt is often used in riveting places with obvious erosion such as ship hull, water storage tank of heating furnace, etc. Countersunk head bolt and 1200 countersunk head bolt are mainly used for riveting places with smooth surface and small load. Semi countersunk head and 1200 half countersunk head bolts are used for riveting places where the surface must be smooth and the load is not large.