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The Development History and Classification of Self tapping Screws and Rivets

The earliest rivets were small bolts made of wood or bone, and the earliest metal deformation bodies may be the ancestors of the rivets we know today. Undoubtedly, they are the oldest known method of metal connection by humans, dating back as far as the initial use of malleable metal. For example, during the Bronze Age, the Egyptians used them to rivet and fasten the six wooden fan shapes on the outer lines of slotted wheels together. After the Greeks successfully cast large statues in bronze, they used them to rivet the various components together.

In 1916, when H.V. White of the British aircraft manufacturing company first obtained a patent for blind rivets that could be riveted on one side, people hardly expected that such rivets would be so widely used today. From aerospace to office machines, electronic products, and sports equipment, it can be said that this blind rivet has become an effective and stable mechanical connection method.

Hollow rivets are mostly invented for the manufacture or maintenance of harness equipment. It is not very clear when hollow rivets were invented, but harness was invented between the 9th or 10th century AD. Riveted horses, like hooves with nails, liberated slaves from heavy labor. Rivets also sparked many important inventions, such as the iron pliers used by copper and iron workers and the shears of sheep's wool.

Solid rivets:

Use self deformation or interference to connect the riveted parts. Solid rivets are generally made of aluminum, copper, iron, and other materials, with a surface treatment of white zinc plating. A rigid connection made by using rivets to connect components, which is non detachable. Small rivets can be cold riveted, while large rivets are hot riveted in a red hot state. Solid rivets can be widely used for cutting tools, stationery books, locks, helmets, automotive hardware bags, baby carriages, automotive clutch steel plates, motorcycle accessories, and household appliances.

Hollow rivet:

A riveting machine (equipment) needs to be used for riveting, and the back of the riveting is turned over to fit the flat rivet. A hollow rivet is composed of a hollow rivet body and a rivet mandrel, and the hollow rivet body is composed of a shaft part and a flange at one end of the shaft part; Insert the head formed on one end of the spindle into the end of the rivet body shaft on the opposite side of the flange of the rivet body, causing the spindle shaft to break from the small diameter fracture part and undergo strong stretching, causing the rivet body shaft to expand and deform. The deformed shaft part and flange are used to install components such as panels. Hollow rivets have a light weight and weak head, and are used for riveting non-metallic materials with low load.