Difference between Cold Riveting and Hot Riveting - Advantages and Limitations

🔗What is riveting fastening process? Applications of riveting
🔗Advantages and disadvantages of riveting

The cold riveting and hot riveting are a classification of riveting based on the temperature of rivet shank.

What is cold riveting?

When the riveting use a cold rivet/ rivet in ambient temperature then it is called cold riveting. Here the shank of rivet mainly subjected to shear stress. This type of riveting is done when using steel rivet having a diameter less than 10mm and suitable for rivet made of comparatively ductile metal like aluminum, copper, brass etc. (nonferrous rivets). The cold riveting used for normal structural joints, wood works, ceiling works etc.

Advantages and Disadvantages cold riveting

Advantages
• Since there is no heating involved, it requires less time than hot riveting.
• Cold riveting do not cause temperature-effect on the joined material.

Disadvantages
• The cold riveting requires more hammering force when compared to hot riveting of same rivet size.
• There is no internal stress development within rivet so the gripping force between the joined parts is less.
• Cold riveting not suitable for leak-proof joints.

🔗Caulking and Fullering of Rivet Joint

What is hot riveting?

In some cases, the rivet shank is heated to red hot before it slid into metal plates. Such riveting is known as hot riveting. The temperature usually 50-70% of the melting point of the rivet. When it cooling down, the rivet starts to shrink, but the reduction in length is prevented by the heads rested on the plate surfaces. It causes developing of tensile stress within rivet, while the connected parts get compressed. That helps rivet to hold the riveted parts tightly. Therefore the hot rivet is recommended for fluid tight joints. Here shank of rivet subjected to both shear and tensile stress.

This type of riveting is used when the nominal diameter of steel rivet is more than 10mm and for rivet made of comparatively less ductile material. The hot riveting is used in hydraulic machines, industrial metal work, leak-proof joints such as pressure vessel, boilers.

Advantages and limitations of hot riveting

Advantages
• It requires less hammering force.
• Tight clamping.
• Make leak proof joints.

Disadvantages
• Not suitable for joining heat sensitive workpiece.
• Require an external heat source to heat the rivet.
• Since hot riveting process includes heating of rivet shank, it is time-consuming.