Fastener

Tools can hold things together.

These tools can join two parts. They can also close a box or a bag.

Many are made of metal. Some are made of strong steel. People use them to build cars and planes. They even help build big houses. You can take them apart easily. This means you can fix things later. These tools help us build our world.

A fastener is a tool used to join objects together.

Most fasteners make non-permanent joints. This means you can take the parts apart without breaking them. This is different from glue or welding. Those methods make a permanent bond.

Fasteners can also close things like bags or boxes.

Many fasteners are made of metal. Most are made of steel. There are three main types of steel used. These are stainless steel, carbon steel, and alloy steel. Some metals get a special coating. This helps them resist corrosion. Corrosion is when metal wears away from water or air.

There are many kinds of fasteners. Some have threads. Threads are the little grooves that help a screw turn. Common types include screws, nuts, and bolts. People use them to build cars and planes. In the U.S., the car industry uses 26 billion fasteners every year. There are many ways to drive a fastener. A hex head fastener has a six-sided top. You can turn it with a wrench. A wing head fastener has wings. These let you tighten it by hand.

A fastener is a device used to join two or more objects together.

Most fasteners create non-permanent joints. This means you can take the parts apart without breaking them. This is different from using glue or welding. Those methods create a permanent bond that is hard to undo. Fasteners can also be used to close things like bags or envelopes. They might even keep the sides of a flexible bag closed.

Some people use magnets or suction cups to hold things. Other things like ropes or chains can join objects too. However, these are not usually called fasteners because they have many other uses.

Many fasteners work using threads. Threads are small grooves that wrap around a part. Common threaded fasteners include screws, nuts, and bolts. You might also see specialized types like studs or threaded rods. The top of a fastener is called a head. Different heads serve different jobs. A flat head sits flush with a surface for a clean look. A hex head has six sides so a wrench can turn it easily. Some have wings so you can tighten them by hand.

Most metal fasteners are made of steel. There are three main types: stainless steel, carbon steel, and alloy steel. Manufacturers also use titanium or aluminum. To stop rust, they might add a special coating. This process is called plating. Common coatings include zinc or chrome. Some use hot-dip galvanizing to protect the metal. When choosing a fastener, people must think about many things. They consider the weight and the temperature of the area. They also look at whether the part will touch water.

Fasteners are a huge part of the world economy. In 2005, the U.S. fastener industry had 350 plants. These plants employed about 40,000 workers. The U.S. uses more than 200 billion fasteners every year. A very large number, 26 billion, are used for cars. This industry helps build planes and big buildings. The Fastenal Company is the largest distributor in North America.

Many industries rely on these tiny parts to stay together.

History shows why we need strict rules for fasteners. In the past, American and British screws did not always fit together. This was a problem for military equipment. World War II helped lead to new military standards. These rules ensure that parts are the same every time. Another important rule is called traceability. This means makers must track where their materials come from. This helps ensure that parts are safe and high quality. In 1988, the U.S. House investigated fake or bad fasteners. This led to the Fastener Quality Assurance Act of 1988.

A fastener is a hardware device used to mechanically join two or more objects together.

Most fasteners are designed to create non-permanent joints. This means the joined components can be removed or dismantled without causing any damage to the parts themselves. This differs from other joining methods like welding, soldering, or gluing. Those processes often create permanent bonds that are difficult to undo. Fasteners can also serve as closing devices for containers like bags, boxes, or envelopes.

Many fasteners operate through the use of threads. Threads are small, helical grooves that wrap around a part. The most common threaded fasteners include screws, nuts, and bolts, which may also involve the use of washers. There are also more specialized threaded items, such as studs, threaded rods, and threaded inserts. Another type is the captive threaded fastener, which is designed to stay in place. Fasteners can also be non-threaded, such as rivets, nails, or even simple items like a paper clip or a clothespin. Even items like cam dowels and cam locks are used to secure flat-pack furniture.

The design of a fastener's head is crucial for its specific job. Flat head fasteners sit flush with a surface to provide a clean, aesthetic appearance. Round heads provide a larger bearing surface, which is useful for thin plastic or sheet metal. Pan heads combine a slightly flattened top with a large bearing surface. For heavy-duty tasks, hex head fasteners are used because they can be easily driven with a wrench. Socket head fasteners are designed for high torque and are driven with a hex key to reduce the risk of cam-out. Other specialized heads include wing heads for hand tightening and flange heads to distribute clamping force.

Material selection is a vital step in industrial applications. Metals are the most common materials used for construction. There are three major types of steel fasteners: stainless steel, carbon steel, and alloy steel. Stainless steel fasteners often belong to the 200, 300, or 400 series. Other common materials include titanium, aluminum, and various alloys. To improve performance, manufacturers often apply special coatings or plating. This process helps enhance corrosion resistance, which prevents rust. Common coatings include zinc, chrome, and hot-dip galvanizing.

Engineers must consider many factors when selecting a fastener for a specific task. They must evaluate the applied load and the stiffness of the fastener. The threading and the total number of fasteners required are also important. Environmental factors are critical, such as temperature and exposure to water. If the environment is corrosive, the material must be able to withstand those elements. Other considerations include the weight restrictions of the project and whether the joint must be reusable. The specific materials being joined also dictate which fastener is appropriate.

The fastener industry is a massive part of the global economy. In 2005, it was estimated that the United States fastener industry operated 350 manufacturing plants. These plants employed approximately 40,000 workers. The industry is closely tied to the production of aircraft, automobiles, and commercial construction. In the U.S., more than 200 billion fasteners are used every year. Of that total, the automotive industry uses 26 billion fasteners alone. The Fastenal Company serves as the largest distributor of these items in North America.

History shows that standardization is necessary for safety and function. Historically, American screws and bolts were not fully interchangeable with British versions. This meant they would not fit British equipment properly. World War II was a major factor in the development of United States Military Standards. These standards ensure that parts are consistent and reliable. A key part of these standards is traceability. This means manufacturers must be able to trace materials back to their original source using methods like bar codes. This ensures that quality standards are met and substandard parts can be identified. In 1988, the U.S. House investigated the use of counterfeit or substandard fasteners in critical infrastructure. This investigation led to the Fastener Quality Assurance Act of 1988, which proposed laboratory testing for fasteners used in critical applications.