In any engineering application, corrosion is an inevitable challenge, especially in mechanical joints where different materials come together under various environmental conditions. Corrosion weakens joint integrity, increases the likelihood of wear-related failures and leads to higher maintenance costs.
As engineers face demands for stronger, lightweight and more durable designs, especially in industries like aerospace and automotive, the choice of joining solutions becomes critical. Wire thread inserts offer an effective and often underappreciated solution to these
challenges. This article delves into how wire thread inserts enhance corrosion resistance in mechanical joints and improve overall joint performance.
The corrosion problem for mechanical joints
Corrosion in mechanical joints is a significant issue, affecting the durability and safety of assemblies. Common forms of corrosion in joints include galvanic, pitting, fretting and crevice corrosion. Galvanic corrosion, for instance, occurs when two dissimilar metals are in electrical contact in the presence of an electrolyte, leading to accelerated degradation of the less noble metal. Similarly, pitting and crevice corrosion can occur in confined spaces and exposed surfaces, gradually weakening the joint and increasing the risk of failure.
- Decreased structural integrity: Corroded joints lose their original strength, making them susceptible to mechanical stress, which could result in cracks and fractures.
- Increased maintenance costs: Regular maintenance and replacement of corroded components increase operational expenses.
- Safety risks: In critical applications such as aerospace, the failure of mechanical joints can have severe safety implications.
Given these risks, it is vital to find a durable and reliable solution that can protect mechanical joints from corrosion.
Enter wire thread inserts - the universal solution to corrosion in mechanical joints
Wire thread inserts are precision-engineered helical coils that are inserted into tapped holes. These inserts provide a resilient and durable threaded surface for screws and bolts. Wire thread inserts have gained popularity because of their multiple benefits, particularly their ability to resist corrosion and enhance joint performance.
Barrier against galvanic corrosion
Wire thread inserts, particularly those made of non-passivated stainless steel or with specialised coatings such as cadmium, can effectively prevent galvanic corrosion. By isolating the fastener from the base material, these inserts minimise the risk of electrical conductivity that leads to galvanic reactions.
Resistance to pitting and crevice corrosion
These inserts shield the internal threads from exposure to corrosive elements. This barrier effect is crucial in environments where components are subjected to moisture and aggressive chemical agents, as seen in aerospace and marine applications.
Enhanced load distribution and shear strength
Wire thread inserts distribute loads more evenly, reducing the risk of stress concentration at the joint. This uniform load distribution not only prevents thread stripping but also minimises the chance of fretting corrosion caused by vibrations or fluctuating loads.
Customisable materials and surface finishes
Wire thread inserts can be manufactured from materials such as phosphor bronze, which is known for its superior corrosion resistance. Additionally, surface treatments like cadmium plating can be applied to further enhance their protective qualities, particularly in highly corrosive environments like saltwater exposure or chemical-heavy atmospheres.
Leveraging KATO® wire thread inserts for corrosion-resistant joints
In the pursuit of efficient and reliable joint designs, wire thread inserts present a versatile solution for engineers contending with corrosion and wear. By acting as both a mechanical reinforcement and a protective barrier, these inserts address key issues in threaded joints, particularly in applications where lightweight materials and extreme conditions intersect.
Acting as both a mechanical reinforcement and a protective barrier, KATO wire thread inserts address key challenges in threaded joints, particularly in applications where lightweight materials and harsh conditions intersect. With an extensive range of materials, finishes, and configurations, KATO wire thread inserts allow engineers to enhance joint integrity, reduce maintenance costs, and achieve optimal performance in demanding environments.
To find out more about our products or to get additional pricing information, contact a member of our team today.
