A new laser profiler has been produced by the Optical Metrology Centre. The system has already been proven in both the offshore oil and water/waste industries. The profiler measures the internal shape of pipes from 150 to 500 mm diameter and is robustly built to operate in hazardous environments. Using a spinning laser, it will take more than 1,000 measurements every 5 seconds for each 360 degree scan. This information is then sent back to a computer screen for display and analysis.
The profile of a pipe or similar structure can identify characteristics such as ovality, cracks, cavitation, wear, or corrosion. In comparative mode, the information can indicate the extent of deformation over a period of time or the thickness of coatings (e.g. epoxy) in ‘before an after’ measurements. The system can also be used to create inventories (like measurements of pipe sizes for relining) and to survey internal structures for replacement and modification. Plastic pipes can be surveyed to assess whether the pipe has been over bent, which may lead to problems in the future. The profiler is likely to have many uses in the measurement of other shapes such as rectangular ducting or moulds and in quality control of key features in manufactured components
The system uses Laser optical triangulation to measure to a point on the surface 1000 times per second. Variations in the surface colour from black to white are compensated for dynamically. The resulting accuracy can exceed 0.2 mm, with small objects being measured more accurately than large ones. The system incorporates an inclinometer for use with vertical profiles to ensure that the profile is always oriented in the same way regardless of the position of the instrument.
The system comes with either Microsoft WindowsTM software or in a Software Development Kit version using National Instruments “Labview” that allows the user to integrate this system into their own applications. The basic software allows the user to perform least squares circle fits and automatically computes ovality measures where appropriate. The resulting information is automatically stored to disk in a sequential manner allowing rapid inspection of pipes or other structures.
The inventor of the laser profiler, Dr Tim Clarke, of the Optical Metrology Centre, said : “We know that many companies need this type of measurement. The profiler can be adapted to meet the needs of any industry needing fast, accurate information about internal structures. We are expecting that this tool will be of interest to users in the process industry, production engineering, and the nuclear industry, as well as the current users. An accurate profile is the key to quality control”
A previous winner of the Innovative Metrology (World Class Manufacturing) Award, the prototype also featured on the BBC’s Tomorrow’s World programme.
Distributed by Optical Metrology Centre
Dr. Tim Clarke
Director of the Optical Metrology Centre
1 Grange Road
Tel: +44 (0)1279 656038
Fax: +44 (0)8700 90014
Email: [email protected]
A JPEG image (1827x1043) of the OMC profiler available and further images are available on request.