What are Threaded Inserts?

Threaded Inserts are shorthand terminology for threaded screw inserts. To the casual observer of machine designs or mechanical components, the threaded insert is usually completely invisible as they sit within joint holes. However invisible they may be, they are essential to machine design components and are specified to provide critical mechanical joint functionalities. They may even make a screw fastener system possible where it was once impossible.

In short, inserts are internally threaded cylindrical metallic components designed to be placed in tightly fitting holes located within part geometries. These cylindrical inserts fit into holes to provide a functional, threaded interface for use within a fastened joint system. Threaded inserts are typically used where the mating parts consist of a plastic or non-structural metallic base material and may not be able to accept internal threads or mating metallic fasteners. This provides a robust mating thread interface and enables metallic fasteners to be used where they may not be otherwise available.

It’s this functionality that is critical to machine designs. There are many reasons why an integrated thread cannot or should not be cut into the native joint material. This is where the threaded insert steps onto the scene to save the machine design, as we will detail below.

Benefits of Threaded Inserts

Threaded inserts impart several critical advantages to the machine design that can roughly be grouped into two of the most crucial design categories below.

1. Structural/Durability Advantages: This is the most significant advantage threaded inserts afford because it spans many aspects of the structural integrity of the joint. Threaded inserts can provide structural robustness to a joint where the rest of the part is lacking.

For example, a metallic threaded insert can accept a metallic bolt in a plastic part. This gives the joint a significant strength advantage compared to internal threads cut in softer metals or plastics. Threaded fastener inserts enable high-strength threads to be used in almost any machine design or wherever a simple hole can be located. The threads cut into threaded inserts are significantly more durable than threads cut in the actual part because they can be specified from high-strength metallic alloys to high-quality thread standards.

2. Production Cost Advantage:The plain fact is that using threaded inserts instead of cutting threads directly into your part can yield savings in part manufacture and assembly times. Threaded inserts can be specified to meet a wide range of geometries and thread sizes to match design requirements precisely. This eliminates the need to tap the hole in the mating part, which can be a costly and time-consuming manufacturing process.

Threaded inserts can be easily installed into existing hole materials in simple production line operations. They can even be installed into blind holes. In this way, threaded inserts are also ideal for an automated manufacturing environment, representing a considerable production advantage over the manual process of tapping or cutting threads into parts.

There are many different variations of threaded inserts across numerous designs and configurations. This whirlwind survey of threaded inserts was designed to show you how they may significantly improve your machine design, not cover the totality of every design feature of various threaded inserts. With this knowledge, you can optimize their placement in your machine designs, and you will likely observe opportunities to realize their benefits in new design areas. To this end, MISUMI carries many sizes and configurations of threaded inserts available to fit unique applications. Explore the selection here.