Buyer’s Guide to Steel Bushings
Steel bushings are the unsung heroes of the manufacturing floor. In short, they take a beating so that the drive shaft and housing on your machines don’t have to. Think of the cartilage around the bones in your knee. Much like a bushing, knee cartilage absorbs vibration, reduces friction, and maintains smooth rotation.
Some types of bushings are referred to synonymously with plain bearings. Depending on their intended use, they can be made using a variety of materials such as rubber, cast iron, nylon, and neoprene. Skateboard bushings, for example, are commonly made of polyurethane.
But in an industrial environment in which low speed / high load applications are the norm, steel bushings are the only viable solution. Due to the heavy loads being exerted on steel bushings, they have less of a cushioning and noise-cancelling benefit than rubber and polyurethane bushings.
Bushing Dimensions
While the total diameter, depth, length-thru-bore, and several other specific dimensions may be required for your specific application, the most commonly searched bushing dimension is bore size. Here at MDS, bushing bore size can range anywhere from ½” to 4-5/8”. It is common for individual products to include a diagram showing the dimensions of the bushing so that you can ensure it will work within your application.
Bushing Types & Sizes
QD Bushings
Quick detachable bushings feature a flange on the outside diameter which is often used to secure the bushing to a sprocket or pulley. More distinctly, QD bushings also feature a split through the flange and taper which makes installation and removal much easier while also improving the holding power by tightening cap screws.
A QT bushing is a specific size of quick detachable bushing which features reverse mounting and, unlike most QD bushings, do not have a setscrew over the key. Other QD bushing sizes include: SD, SK, J, F, E, SF, SDS, SH, and JA.
Idler Bushings
The most prominent feature of an idler bushing is its permanently lubricated ball bearing units. A threaded shaft passes through the ball bearing unit of the bushing and is secured on the other side with a locking nut. This allows sheaves and pulleys to be removed without removing the idler bushing.
Taper-Lock Bushings
Like QD bushings, taper-lock bushings also feature a split side for enhanced clamping power. Unlike QD bushings, taper-lock bushings gradually taper along the length-thru-bore in order to provide an even tighter fit on the drive shaft. This tapering allows for a shorter length-thru-bore and narrower sprocket hubs. Taper-lock bushing sizes include: 1008, 1108, 1210, 1215, 1310, 1610, 1615, 2012, 2517, 2525, 3020, and 3030.
Steel bushings, like most power transmission products, come in a wide variety of types and sizes. For help determining which particular product you need, request information from the professionals at MDS.
