It should be inspected with a computer-probe type of device, such as a roundness machine (or maybe some CMMs can do it). Assuming this is based on ASME Y14.5, the default algorithm to use is the "minimum radial separation." For this reason, it can't be done very well with traditional open-setup methods.
John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems
Tolerance zone of 0.25 is formed on the taper surface? If Cylindricity tolerance zone is horizontal when it is placed at the dia 25.4 than other end of dia 24.6 will not be on tolerance zone.
so only size tolerance is accepted and Cylindricity is failed. Is this same case in Flatness and straightness also when part produced in worst condition?
Yes, form of a surface (flatness, straightness, cylindricity, and circularity) is independent of size. Size is simply size, and form looks for consistency along the size.
John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems
ashivu123
Typical form deviations for a cylindrical surface are straightness, lobing, ovality and taper, so a cylindricity tolerance will limits the straightness, roundness and taper of a diameter, it will not control the flatness on this case.
The picture on the left is not a cylindricity tolerance, because it tapers down (going from left to right). It looks to be only controlling straightness.
John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems
