What Is a Ring Shim?
A ring shim is a specialized shim designed to adjust position, level, and spacing between parts or between parts and equipment. Characterized by their ring shape and uniform thickness, ring shims facilitate the absorption of dimensional and accumulated tolerances during the assembly of multiple parts, enabling precise positional adjustments in the field.
Applications of Ring Shims
Ring shims find widespread use in machinery and equipment assembly, where precise spacing or positional adjustments between components are required. Their applications include:
1. Position Adjustment of Bearings and More
Inserted into the inner and outer rings of bearings, ring shims aid in securing and adjusting positions axially. They are crucial for setting bearing preload in angular and tapered roller bearings by aligning the inner and outer rings. Similarly, ring shims adjust the shaft positions of gears and pulleys, mirroring their application in bearings.
2. Position Adjustment with Screw and Bolt Holes
Ring shims enable positional adjustments at screw or bolt fastening surfaces without the need for specially shaped shims. By inserting ring shims into threaded holes, the fastening surfaces’ positions can be finely adjusted, also facilitating height adjustments for pins.
3. Position Adjustment on Flange Surfaces
Placed around the inner and outer circumference of flange surfaces, ring shims allow for positional adjustments without special shim shapes, avoiding fastening holes for seamless integration.
Principle of Ring Shims
Ring shims serve as precision components for fine-tuning spacing and positions, thanks to their uniform thickness and ring shape. They are available in a broad range of thicknesses, from tens of micrometers to several millimeters, and are made from materials like steel, stainless steel, copper, and brass.
Types of Ring Shims
Beyond the standard ring shape, ring shims come in several variations:
1. Notched Type
Notched (or split)-type ring shims feature a partial notch, allowing for easy insertion and removal during assembly without fully disassembling bolts or shafts. Caution is advised to prevent tilting by avoiding notch alignment when using multiple shims.
2. Laminated Type
Laminated ring shims consist of ultra-thin layers bonded together, enabling thickness adjustments by peeling off layers as needed.
Other Information on Ring Shims
Usage Considerations
When using ring shims, it’s essential to minimize the stack to avoid contamination or alteration of thickness. Ring shims are distinct from washers and spacers, which are used for more significant height adjustments. Often, ring shims are marked or color-coded for easy identification of thickness and to prevent loss or reflectivity issues during assembly.