How to prevent fastener galling

How to Prevent Fastener Galling

Fastener galling is a common problem that occurs when threads of fasteners, such as nuts and bolts, become damaged due to friction and heat generated during the fastening process. This can lead to thread damage, seizure or even failure. Fortunately, there are several ways to prevent fastener galling. In this article, we’ll explore some effective methods to avoid fastener galling and ensure the longevity of your fasteners.

1. Understanding Fastener Galling

Galling is a form of wear that causes materials to stick or weld together due to friction and heat. This phenomenon is common in stainless steel fasteners and other materials with high friction coefficients. When the two threaded surfaces contact each other, small amounts of material transfer from one surface to the other. These transferred materials form a bond and lead to seized or damaged fasteners.

2. Choosing the Right Materials

The selection of materials is crucial for preventing fastener galling. Materials with a low friction coefficient such as brass, aluminum, and titanium are less likely to gall than materials with high coefficients such as stainless steel. Therefore, it is important to consider the environment in which the fasteners will be used, the load they will bear, and the chemical properties of the materials.

3. Lubrication

One of the most effective ways to prevent fastener galling is to use a suitable lubricant. Lubrication reduces friction and heat during the fastening process, preventing galling and extending the life of the fastener. There are various types of lubricants available for different applications, such as silicone grease, molybdenum disulfide, and graphite. It is essential to choose the right lubricant for your fastener and use it in the appropriate quantity to achieve optimal results.

4. Anti-Seize Compounds

Anti-seize compounds are specialized lubricants designed for use in high-pressure and high-temperature applications. They work by creating a barrier between the threaded surfaces and preventing corrosion and oxidation. Anti-seize products are available in various forms such as pastes, sprays, and powders. They are highly effective at preventing fastener galling, but it is still important to select a product that is specifically designed for your application.

5. Heat Treatment

Heat treatment is another effective method of preventing fastener galling. The process involves heating the fasteners to a specific temperature and then slowly cooling them. This modifies the structure of the metal, improving its strength, ductility, and resistance to corrosion. Heat treatment is recommended for high-stress and high-temperature applications, such as aerospace or automotive assembly.

In conclusion, fastener galling is a common yet avoidable problem that can cause significant damage to your applications. By understanding the causes of galling and using appropriate prevention methods, you can ensure the longevity of your fasteners and avoid costly repairs or replacements. Remember to choose the right materials, use lubrication, anti-seize compounds, and heat treatment where necessary. With these steps, you can prevent fastener galling and maintain the reliability of your fasteners for years to come.