Dimension measuring for bearings parts
The Universal Length Measurer (ULM) is a kind of length measuring instrument that integrates fine mechanics, an optical system and electrical parts into an organic whole. This instrument is used for direct measurement and comparative measurement for dimensions of parts and components. It also offers additional equipment for carrying out various special measurements.Bearing “tolerances”, or dimensional accuracy and running accuracy, are regulated by ISO standards. For dimensional accuracy, these standards prescribe the tolerances necessary when installing bearings on shafts or in housings. Running accuracy is defined as the allowable limits for bearing runout during operation. Dimensional accuracy constitutes the acceptable values for bore diameter, outer diameter, assembled bearing width and bore diameter uniformity in chamfer dimensions, allowable inner ring tapered bore deviation and shape error. Average bore diameter variation, outer diameter variation, average outer diameter unevenness as well as raceway width and height variation (for thrust bearings) are also included. Running accuracy constitutes the acceptable values for inner and outer ring radial runout and axial runout, inner ring side runout and outer ring outer diameter runout. All these dimensions of the bearing parts are measured with high-quality equipment.