Ultra High Precision Ceramic Ring Gauges Ceramic Setting Ring Innovacera developed a series of ceramic accessories for Inside Micrometers, Holtest and Dial Bore Gages. The ceramic material used mostly is zirconia. The zirconia ceramic setting ring advantages: High wear resistance and long service life The coefficient of thermal expansion is very small, the effect of temperature is very small The hardness is very high, there is no need to worry about surface scars. Ring gauge management is simple (regular inspection interval is long, saving cost). The Zirconia Ceramic Ring Gauges Technology: Surface Roughness: Not more than Ra0.1um Straight Angle: 0.05/φ100 Parallelism: Not more than0.015mm Each 0.5mm as one size, from 1mm to 50mm. Size Dimensional interval Roundness Outer diameter tolerance: Inner diameter tolerance Hardness 1-29mm 0.5mm 0.5um ±1um ±1um 1200HV 30-50mm 0.5mm 0.8um ±1.6um ±1.5um 1200HV Some Zirconia Ceramic Ring Gauges Innovacera made and size detail: ...