There are many factors which need to be considered when you’re specifying a shaft collar for your application. These include holding power, operating conditions, installation mechanism and material.
The key performance factor that designers usually look for in a shaft collar is its holding power. In a set screw shaft collar, the holding power is dependent on the material of the shaft, as this impacts how far the screw is able to impinge into the shaft. In a clamp style shaft collar, the bore size and concentricity are far more significant in calculating the holding power of the shaft collar.
The holding power of a shaft collar can be further increased by opting for a black oxide surface treatment. This enhances the collar’s holding ability thanks to its anti-stick properties whilst helping to maintain the torque rating.
If you’re looking for a shaft collar which is resistant to corrosion, you may choose to opt for zinc plating. This provides an excellent resistance to corrosion, making it ideal for use in wet and contaminated environments. However, zinc plating reduces the holding power of the shaft collar.
The material that both the shaft collar and the screws are made from will also impact on the performance of the collar. Aluminium is a popular choice, resulting in a lightweight shaft collar with good holding power. If you’re looking for the highest levels of holding power, steel may be the right option. For increased corrosion resistance, stainless steel is typically the material of choice.
It’s important to ensure that both the shaft collar and the screws are suited to the operating environment. All too often, designers specify the perfect shaft collar for an application, forgetting the screws. Whilst the shaft collar will be able to withstand the harsh environment, the screw will not, leading to reduced performance and premature failure.
Although the majority of shaft collars are manufactured from aluminium, steel or stainless steel, there are also some materials available which are less common. Plastic shaft collars are lightweight and low in price, but have a much lower holding power. Titanium shaft collars have a very high cost but do not outgas, making them perfectly suited to cleanroom environments.
Choosing the right shaft collar is an important part of the application design process. Choose the wrong shaft collar and your performance will be compromised, potentially leading to premature failure and machine breakdown.
If you’re unsure when it comes to selecting the right shaft collar for your application, it’s always best to consult a specialist. After all, they’re the experts.
Our team can help you identify the appropriate shaft collar design, material, and finish for any application. To see how our team can support yours, please contact us or request a quote today.