In various fastening applications, riveting is often chosen because of its light weight & high firmness, low cost, easy installation, high durability and reliability. In order to assemble the parts correctly, hole preparation is critical. In this article, follow us to understand the rivet sizes and dimension details, including how to express and determine it, as well as the standard rivet hole size chart for reference.
The rivet sizes or dimensions commonly applied including the rivet diameters and lengths, which can be indicated in both imperial (inch) and metric (mm) series.
– Imperial: rivet diameters are commonly measured in 1/32-inch increments and the lengths are measured in 1/16-inch increments, expressed as “dash numbers”. For example, the “dash 3 dash 4” means a 3/32-inch diameter and 4/16 -inch length. Rivet lengths are also probably expressed in half sizes, and have a dash number such as -3.5 (7⁄32 inch) to indicate they are half-size.
– Metric: rivet diameters and lengths are measured in millimeters. Rivets with diameters between 2-20 mm and lengths between 5-50 mm are common for general use.
If the dimensions of rivets are not specified on the design drawing, you can determine the rivet size based on the following rules:
Minimum Diameter of Rivet Shank (D) = Thickness of all sheets to be joined (S)/4
Length of Rivet Shank (L) = S + Allowance (A)
A=1.5 *D (For rivets of diameters of the rivet shank up to 20 mm)
Please note that the value of D (diameter) is the minimum option of the rivet shank diameter, and the rivet shank must be longer than the thickness of all materials to be riveted, otherwise, there will be no allowance for fastening. The allowance depends on the type of rivets and applications. For example, if the calculation result of the diameter is 2mm and the result of length is 12.5mm, you can choose a rivet 3 * 12.
The rivet diameter is related to the drill required to make a hole through which the rivet pass. After determining the rivet size and putting the sheets, the hole size must be marked for drilling. So, it’s important to know the rivet hole size before the installation. Generally, the actual diameter of the rivet is slightly smaller than that of the hole need to be drilled. Ideally, a rivet should be placed in a hole which is 4-6 thousandths of an inch larger in diameter. This allows the rivet to be easily and fully inserted, then make the rivet expand, tightly fill the gap and maximize strength.
Standard Rivet Hole Sizes & Drill Sizes