Rivet mandrels are widely used in industrial manufacturing, construction, automotive maintenance, and other fields as fasteners, with advantages such as easy installation and firm connection. During the process of using rivet mandrels, choosing the appropriate mandrel size is crucial, as it directly affects the riveting effect and connection quality. This article will introduce in detail how to correctly select the mandrel size of the rivet mandrel gun.



Firstly, we need to understand the basic structure and working principle of the rivet mandrel. The rivet mandrel consists of the rivet body and the mandrel (core pin), which is used to pull the mandrel out of the rivet body with a special riveting gun, causing the rivet to expand and thus fasten the connected parts. In this process, the role of the mandrel is to hold the mandrel and apply tension, so the size of the mandrel must match the diameter of the mandrel.



1. Select the mandrel according to the rivet diameter



The specification of rivet mandrels is mainly represented by the diameter of the rivet body, such as Φ3.2mm, Φ4.0mm, Φ4.8mm, etc. Different diameters of rivets require matching with different sizes of mandrels. Generally, the inner diameter of the mandrel should be slightly larger than the diameter of the rivet mandrel to ensure that the mandrel can be inserted smoothly and tightly clamped. If the mandrel is too small, it may cause the mandrel to jam or break; if the mandrel is too large, it may lead to loose clamping, affecting the riveting effect.



The common rivet mandrel diameter and mandrel matching relationship is as follows:



- Φ3.2mm rivet: use Φ2.4mm mandrel

- Φ4.0mm rivet: use Φ3.2mm mandrel

- Φ4.8mm rivet: use Φ4.0mm mandrel



The specific size should be referred to in the manual of the riveting gun and rivet, to ensure accurate matching.



2. Select the mandrel according to the rivet material and type



Rivet mandrels of different materials (such as aluminum, steel, stainless steel, copper) require different tensile forces during riveting, which also affects the selection of the mandrel. For example, stainless steel rivets with higher hardness may require tools with greater tensile force and more wear-resistant mandrels. In addition, some special types of rivets (such as multi-drum rivets, closed-end rivets) may also require special mandrels to ensure the quality of riveting.



3. Check the mandrel wear condition



Even if the appropriate mandrel is initially selected, the holding effect may be affected due to wear during long-term use. Therefore, it is necessary to regularly check whether the mandrel is deformed, worn, or cracked, and replace it in time if necessary to avoid riveting failure or tool damage due to poor mandrel quality.



4. Refer to the tool manual and manufacturer's recommendations



Each type of riveting gun has its applicable rivet specification range. Before use, it is necessary to read the product manual carefully to understand the supported mandrel types and rivet sizes. For professional users or industrial applications, it is recommended to have a variety of mandrel sizes to meet the riveting needs in different scenarios.



Conclusion



Choosing the appropriate mandrel size is a key link in ensuring the quality of rivet mandrel installation. Only by correctly matching the rivet specification and material, and combining with reasonable selection based on actual working conditions, can we ensure the smoothness of the riveting process, the firmness of the connection, improve work efficiency, and extend the service life of the tool. It is hoped that this article will be helpful to you when using rivet mandrels.