Valve inspection

Measuring System: MicroCam-3D, MicroCam-4D
Keywords: valve, tube, metrology, inspection, non-contact

Conventional methods of valve inspection using a contact profilometer are making way for the newer non-contact valve inspection technology.

Although all the standards of surface roughness all over the world are set as per the observations noted down by a contact profilometer, the convenience of non-contact inspection stations and the faster process of using such state of the art valve inspection technology are obvious reasons why more experts are opting for the new methods.

Novacam’s fiber-based low coherence profilometers easily reach inside valves with fiber-based probes  to acquire high-precision surface measurements:

  • A customized inspection station helps acquire the inner surface of a cylinder in one continuous motion
  • A single probe is rotated to acquire micron-precision dimensional information of cylinder interior
  • Simultaneous dimensional and surface roughness check

Inspection of valve interior walls with fiber-based optical probe mounted on a custom-built inspection station

Inspection of valve interior walls with fiber-based optical probe mounted on a custom-built inspection station – click for closeup

Advantages of a Customized Valve Inspection Station

In metrology, it is all about precision. Any device or method that can stretch the precision levels for a measurement will ultimately prevail over conventional methods which give less precise readings.

The biggest disadvantage of contact profilometers is that it is a time consuming method. not being an integrated solution but rather a direct manual technique, it takes longer to note down the measurements of surface roughness and dimensional info. This can be a ‘no go’ in time critical onsite inspections.

The customized valve inspection station based on non contact profilometers are easily adapted for a specific valve, provide for a much faster process. Also it takes one probe and one rotation of it to check the interior dimensions of the valve and the surface roughness simultaneously. The traditional methods involve two different instruments to check the internal dimensions and the surface roughness but with non contact profilometers, it needs only one probe and both the observations can be recorded.

Precision of Optical Profilometers

Non contact optical profilometers can have a spot size at the micrometer levels which automatically enhances the precision of the recording. The measurements are based on the light reflected from the internal surface of a valve cylinder and hence the speed is also high in customized valve inspection.

Optical profilometers can check the entire internal environment of the cylinder in one rotation of a single probe and obtain micron level precision.

Offsite Valve Inspection

If the valves are very small or in hostile conditions, the only method to measure surface roughness is by a fiber based optical profilometer. These are used to launch offsite probes and they are not only precise but the fiber probe is very small hence it can easily enter areas of a cylinder or tube that cannot be accessed using other methods. Since the detector in this process is at a remote location, many inaccessible areas can be easily measured using fiber based optical profilometers.