Types of Solid Rivet

Solid rivets are available in a variety of shapes and metals. The common types of British rivet are:

• The Snap Head: It is used for general purposes.

FIGURE

• The Mushroom Head: In this, less resistance to the air is essential.

FIGURE

• The Countersunk Head: A flush finish is required for countersunk heads. These types of rivets are available in a variety of different head angles, usually 60°, 90°, 100° and 120°, with the most common being the 100°.

FIGURE

In the USA, the common heads are the universal (similar to the mushroom head) and the countersunk head.

Rivet Materials

Unless otherwise stated, the rivets must be of the same material as the work being riveted. The rivet material may be identified by markings, colour, anticorrosion treatment or magnetic properties.

Solid rivet markings are usually situated on the head or tail of the rivet. These rivets can be made from a variety of materials with aluminium alloy being the most common. Tubular rivets are not marked.

The material and specifications of British and American rivets are not the same. The type of rivet used for repair is dictated by an aircraft’s maintenance manual. Permission from the aircraft manufacturer is required before any changes, to rivet specification, are allowed. When in doubt as to the identification of rivets, reference should be made to the packaging label.

Basic Rivet Location Terminology

Basic terminologies (refer to below figure) are employed to describe the location of rivets relative to each other and to the limiting boundaries of the assembly.

The most common terms are stated below.

• Pitch: It is the distance between two rivets in a row, measured centre to centre. It should be at least four times the rivet diameter (4D).
• Spacing: It is the distance between adjacent rows and it should be between 3D and 4D. A zigzag pattern of spacing is normally used for liquid-tight joints.
• Land: It is the distance between rivet centres and the edge of the metal sheet. It should not be less than 2D.
• Allowance: It is the amount of rivet shank that protrudes beyond the material before the rivet is formed.
• Clearance: It is the amount that the rivet hole is larger, than the rivet shank diameter.

FIGURE