The automet® system is primarily used in it's capacity for pipe spool measurement and on site collection of piping/structural information. It does however have many other applications, one of which is the setup and alignment of mobile pipe cutting machines. By establishing a local orientation system relative to the pipe we can accurately position the cutting tool to provide a true straight cut, not corrupted by any deformations of the pipe.
mltech were first approached by Glacier in 2014 when they required a higher degree of control and accuracy for their cutting tool setup. Traditional methods, especially on larger pipe work, were not producing satisfactory cuts. This resulted in a large amount of man hours being wasted on grinding pipe ends. The current methods being used at this time involved measuring back from the pipe end to the face of the cutting tool at multiple locations around the pipe, then tightening the tool once all measurements were equal. A spirit level could also be used to check the vertical plane. The problem with this method was that the pipe ends were often not cut square to begin with, making it impossible to take an accurate measurement back from the face. With this in mind we created the Local Tubular Orientate routine to become part of the automet® software package.
The Local Tubular Orientate works by measuring either end of the pipe to provide information on the plane, ovality, end squareness and a centre point. The centre points at either end are created taking into account any out of roundness errors and as a result are the best fit centres. A line is plotted between the best fit centres at either end, which is then reference for the orthogonal plane to which the cutting tool is set. This allows the tool to be set perpendicular to the centre line of the pipe without any ovality or end squareness issues corrupting the results.
The cutting tool is set live using a Leica total station, in conjunction with a laptop running the automet® software suite. No post processing is required to produce survey results and the survey its self can be carried out comfortably by one person, making the whole process quick and easy. There is very little actual survey work required for the setting of the tool. Once the local orientation has been established it is simply a case of measuring to a prism held in place by a magnet on the face of the cutting tool. The cutting tool is rotated around at ninety degree intervals taking a measurement to the prism at each, taking four measurements in total. Within the automet® suite these points will be shown and can then be used to adjust the tool. Once adjusted it is simply a case of re-measuring the four points on the cutting tool to check the position. This process is then repeated until all observations are within tolerance. The system can achieve repeatability of up to +/- 0.2mm