Riveting Process     

Stainless steel rivets commonly come in various types such as dome head, flat head, countersunk head rivets, blind rivets, hollow rivets, and semi-hollow rivets. These are typically used to connect components through their own deformation (cold riveting for sizes smaller than 8 millimeters, and hot riveting for larger sizes). However, there are exceptions, such as the nameplate on a padlock, which is attached by riveting through an interference fit between the rivet and the lock body.

Additionally, there are pop rivets, consisting of two parts: a thicker section with a cap and a hole in the middle, and a thinner section with a cap. During riveting, the thinner rod is inserted into the thicker rod.

The stainless steel rivet riveting process involves using a metal cylinder or tube (the rivet) with a slightly smaller diameter than the hole in the components to be joined. The rivet is passed through the parts that need to be connected, and then both ends of the rivet are hammered or compressed to cause the metal cylinder (tube) to deform and thicken, forming rivet heads at both ends. This secures the components and prevents them from detaching under external forces. The riveting process includes cold riveting and hot riveting. Cold riveting is done at room temperature, while hot riveting is used in applications with higher requirements, such as steel beam connections in iron bridges. During hot riveting, the rivet is preheated, inserted into the rivet hole while red hot, and the stress generated during the cooling process ensures a tighter connection. Riveting typically requires work from both sides, but the introduction of blind rivets has made single-sided operations more convenient.

Methods for removing stainless steel rivets:

1. Use an appropriately sized drill to bore through the rivet and remove it.

2. Use a small grinding wheel to grind down the rivet and then use pliers to extract it.

3. Insert a metal strip into the gap between the rivet and the item, then insert a screwdriver between the metal strip and the rivet, and apply force to turn it. With a few gentle twists, the rivet will come out without damaging the item.

Introduction to Riveting Process

Riveting Methods

The process of joining two or more components using rivets is called riveting.

Classification

1. Hinged Riveting: Assemblies can rotate relative to each other. It is not a rigid connection. Examples include scissors and pliers.

2. Fixed Riveting: Assemblies cannot move relative to each other. It is a rigid connection. Examples include angle rulers, nameplates on padlocks, and bridge structures.

3. Sealed Riveting: The rivet joint is airtight, leak-proof, and corrosion-resistant. It is a rigid connection.

The process involves drilling, countersinking, removing burrs, inserting the rivet, using a rivet gun to form the rivet (or manual setting, thickening, rivet forming), and finishing.

Riveting can be classified into cold riveting and hot riveting.

Blind riveting is used when a simple and convenient process is needed.

This type of rivet is the most common solid flat head rivet. To make such rivets, a cold heading machine, also known as a heading machine, is used. The model to be used is selected based on the shape of the rivet head and the diameter of the shank. For example, rivets with a diameter of less than 3mm use a No. 0 cold heading machine. Rivets with a diameter of less than 7mm can be made using a one-die two-blow or a two-die four-blow cold heading machine. The product's special shape and the greater deformation required, the more dies and strokes are required. For example, there are three dies and three blows, four dies and four blows, five dies and five blows, and so on.

If you don't have a rivet gun, you can use a hand hammer to replace it for rivet installation. When riveting, use a hand hammer to strike the rivet head until the rivet core is flush with the rivet head, completing the riveting operation. Pop rivets are especially useful in cases where it is inconvenient to use regular rivets (requiring riveting from both sides) or where a rivet gun is not available. However, it is essential to use a rivet gun for blind rivets.

Rivet installation tools are compact and can be easily carried, similar in size to electric drills, and they generate very little noise during operation, which does not have a significant impact on the physical and mental health of workers. Riveting can generally be performed by a single operator, making training relatively easy. The construction process is simple and convenient, requiring minimal time and effort, resulting in low cost.

Riveting Process Requirements

When permitted by lifting and transportation conditions, longer sheet materials should be used to minimize joints, which can improve the insulation and waterproofing of the steel structure factory building's sheet materials.

At the ends of each color steel plate on the steel structure factory building, the density of screws should not be less than three screws, and rivets should be used to connect the overlapping parts, with waterproof treatment.

When overlapping the bargeboard color steel plates, they should be oriented away from the wind, with an overlap length of more than 2-5 cm, and the spacing of rivets should be less than 50 cm. The color steel plate surface should not have scratches or rust. If present, remedial measures such as painting or replacement should be taken.

Rivet Compression Process

From the working principle: Riveting machines are generally divided into two types, radial riveting and swing peening riveting. Both types of riveting machines have an eccentric angle.

In contrast, compression riveting is a hydraulic or pneumatic direct compression riveting, without an eccentric angle. In simple terms, it's gentler than punching and forming. In terms of pressure: Riveting machines have greater riveting force compared to compression riveting machines. For example, a riveting machine with a maximum riveting pressure of 34 kN is equivalent to a compression riveting machine with a pressure of 340 kN. In terms of riveting effects: Riveting machines form the rivets through a motion path, which results in better riveting effects and better stress relief, especially for rivets that are brittle. Compression riveting is more likely to cause cracks.

Rivet Riveting Process Flowchart

If the rivet is a semi-hollow type, it needs specific molds designed to support the rivet relative to the product's shape. Then, you can use a Rivet machine to perform the riveting.

If you need to rivet the rivet into a semi-hollow head, it's also straightforward. Design a customized rivet head of the desired size and use it with a Rivet machine for the riveting process.

When permitted by lifting and transportation conditions, longer sheet materials should be used to minimize joints, which can improve the insulation and waterproofing of the steel structure factory building's sheet materials.

At the ends of each color steel plate on the steel structure factory building, the density of screws should not be less than three screws, and rivets should be used to connect the overlapping parts, with waterproof treatment.

When overlapping the bargeboard color steel plates, they should be oriented away from the wind, with an overlap length of more than 2-5 cm, and the spacing of rivets should be less than 50 cm. The color steel plate surface should not have scratches or rust. If present, remedial measures such as painting or replacement should be taken.

Rivet Removal Tips:

1. The air pressure source does not reach the required level.

2. The air supply pipe is not well sealed, or the air supply pipe is damaged, causing insufficient suction in the pneumatic riveting tool.

3. There is too much iron debris in the gun nozzle, leading to improper air passage and insufficient suction. The gun nozzle is blocked.

Rivet Forming Process

Semi-hollow rivet self-piercing riveting is a cold forming process that creates a strong interlocking connection between the rivet and the sheet metal. It mechanically locks components together and is used to join various combinations of sheet materials, including galvanized layers, organic coatings, or pre-coated steel sheets, as well as aluminum-steel composites or plastic-metal hybrid sheet materials. Semi-hollow rivet self-piercing riveting can be applied to steel sheets with a total thickness of up to 6mm and lightweight alloys with a total thickness of 10mm.

Semi-hollow rivets are typically made from high-strength steel and designed with specific shapes and dimensions to meet riveting requirements. The die is usually made of die steel.

To achieve the desired results, it is essential to follow these basic principles:

1. Avoid riveting fragile materials such as glass or brittle plastic sheets.

2. The base sheet should preferably be made of metal with an elongation rate of over 12%.

3. When joining sheets of different thicknesses and strengths, it is recommended to place the thinner, less rigid sheet on top of the thicker, stronger sheet.

4. For optimal riveting results, the thickness of the base sheet should exceed one-third of the total thickness of the sheet assembly.

5. Self-piercing riveting requires simultaneous pressure from both sides of the workpiece, and sufficient space should be available on both the upper and lower sides to ensure this.

6. In the self-piercing riveting process of semi-hollow rivets, when joining two layers of the same metal material, the thicker one should be placed on the bottom layer. When joining two layers of different metal materials, the more ductile material should be placed on the bottom layer. When joining metal and non-metal materials, the metal material should be placed on the bottom layer.

Peak Fasten Tech has been dedicated in developing and manufacturing different kinds of custom rivets for many years. The typical rivet types include hollow rivets, tubular rivets, semi-tubular rivets, eyelets etc. Just feel free to contact for any inquiry or consultants for problems you meet in the application of rivets in your industry. All your query shall be responded within 12 hours.