Shim Alignment

Alignment Shims in Shaft Alignment Applications

In shaft alignment, the driven machine is usually considered as a stationary machine element and its driver is usually considered to be movable. The movable rotational axis is compared to that of the stationary. When these axes are not the same (i.e. not collinear), then the two shafts are misaligned.

Shim alignment corrects by adding or taking away

Misalignment can be offset or angular, which measurement by dial indicators or laser sensors will reveal. The axial locations of these sensors define the measurement planes. Correctional planes, then, are where shims for alignment can be added or removed to the driver's feet or platform to affect alignment. Foot values should be used only to make alignment corrections, as using them to calculate misalignment makes any small measurement errors worse.

What is an alignment shim?

An alignment shim is a thin piece of metal placed beneath the feet of machinery to align one rotating shaft more precisely with another. Inserting or removing alignment shims elevates or lowers one machine, most commonly the driver or motor, to marry its centerline with that of the driven unit, typically a pump, fan, turbine, or some other device that requires rotation to work.

Benefits of alignment shims for industry

Precision-engineered shims of high-quality stainless steel and laminated brass enable industries of every kind to achieve near-perfect alignments of machines at installation and during routine maintenance checks. Pre-cut steel shims for alignment offer a number of benefits worth noting:

• Sizes to fit virtually all machine feet and typical bolt sizes 
• Many thicknesses available for precise shim alignment corrections 
• Permanent labeling indicates thickness for easy identification 
• Perfect flatness over the entire face ensures stable, consistent support in any application 
• Burr-free edges and rounded corners lessen the chance of injury to technician who positions shims 
• Tab provides handling point for easier, safer insertion and removal 
• Resists corrosion from acid or alkali exposure 
• Packages of multiple alignment shims meet individual requirements

From VibrAlign: Hog brand pre-cut steel shims and shim kits

VibrAlign offers top-quality Hog brand shims for alignment with the following features:

• Oversized tab for safer insertion 
• Corrosion-resistant 300 series stainless steel 
• Full kits of 20 and half-kits of 10 
• Packages of 20 replacement shims, in 13 thicknesses, with each thickness available in 2x2, 3x3, 4x4, and 5x5 sizes.24-hour order fulfillment 

For more on alignment of shims or alignment in general call VibrAlign at 800-394-3279.

Want more information on alignment shim usage?

VibrAlign engineers and technicians are experts in all alignment methods and applications. The company provides a range of alignment services, including training, to suit the needs of individual customers. VibrAlign is the North American distributor for the USA for the entire line of Fixturlaser laser alignment systems and products. For further information on alignment shims or anything else about precision alignment, please contact VibrAlign at 800-394-3279 or by email.