Analysis of Measurement System Accuracy Based on 2D Laser Triangulation Scanner When Measuring Soiled Pipe Thread Pitch and Height

Abstract

An experimental setup was assembled for precision measuring of soiled pipe nipple thread parameters. The experimental setup error was evaluated in accordance with ISO 10360-8 standard. Law of distribution was defined for thread pitch and height values measured by setup. Special composite material casts were used to verify laser scanner accuracy during thread pitch and height measurement. Casts from the thread surface were measured using a precise optical microscope to find pitch and height values with the accuracy ten times greater, than the accuracy of the assembled experimental setup. Fifteen independent measurements were made to evaluate the relative error of the pitch and height values. Comparison of the microscope and setup measurement results was made to evaluate the absolute error of the pitch and height values. The possibility of achieving by 2D laser triangulation scanner of regulatory requirements to the measurement accuracy of API 5CT standard for the soiled threaded pipe was confirmed experimentally.