Thread inserts

There are more options available than you might think and selecting the right one for the job is critical.

Thread inserts are not just used to repair broken threads.

They are also used in OEM applications to strengthen threads in softer materials such as aluminium and magnesium. Because they are available in several forms it can be confusing as to which type should be selected for a particular job and why.

PowerCoil ‘wire thread’ inserts are the most well known and also the most versatile. To the uninitiated they might look like a simple spring, but in fact they are created with a specific diamond profile to suit the thread type required (Metric Coarse, UNC, BSW, etc).

Wire thread inserts also have a ‘tang’ at one end to aid installation. So what are the advantages of wire thread inserts? Firstly, they are inexpensive when compared to other inserts, simple to install, yet extremely tough, wear resistant and corrosion resistant. Secondly, they allow the stress loading from the bolt or similar threaded part to be more evenly distributed over the threads in the parent material, as the illustration shows.

Loksert threaded inserts are manufactured either from solid C1215 carbon steel or solid AISI303 stainless steel. They have pre-assembled dove-tailed locking keys which are driven into the parent material to create a positive mechanical lock against rotation.

This makes Lokserts ideal for applications where there is heavy wear and vibration such as the transport industry, mining, earthmoving and military equipment. They are used in high volume OEM applications such as railway carriages, transmission housings and suspension units.

One other advantage of Lokserts is that standard taps can be used to install them rather than the specialized STI taps used with PowerCoil inserts. This can mean a cost saving when an insert is required for low volume thread repair.

Bondserts are not well known in Australia but they should be. They are a simple and fast solution to a stronger fastener assembly in virtually any ferrous metal. Wind the insert into the tapped hole and the microencapsulated adhesive begins to set, and the newly installed inserts are fastener ready in 3-5 minutes. Maximum insert strength is achieved in 72 hours, at which point the Loctite™ 204 adhesive also seals against liquids and gases up to 6,000 psi.

Tapserts complete the picture. They are self-tapping inserts that are driven into a pre-formed or pre-drilled retaining hole. The cutting slots effectively tap the hole as the insert is wound into the parent material. Tapserts are ideal for use in low shear strength materials such as alloys, plastics and castings.

Whatever your thread insert requirement, Bordo has the expertise to help you select the most suitable type and guide you through the installation process.