Evaluation of internal surface roughness in fiberglass pipes by surface roughness instruments

Abstract

Abstract Introduction: Investigation of the internal surface roughness of fluid transmission systems pipes is very important in the amount of energy loss. Different concepts and methods have been used to examine surface roughness. Some of these methods are based on roughness measurement devices and equipment in this field. Significant researches are done in surface roughness measuring in steel, copper, plastic, or coated pipes. Methods: In this study, the inner surface roughness of fiberglass pipes, has been evaluated using laboratory methods and roughness measuring devices in several diameters and two different types. Calibration and verification results of the surface roughness tester machine on sandpaper and U-PVC pipe wall surfaces are evaluated. In addition, the effect of roughness parameters and their calculated surface roughness and time using of fiberglass pipe have been investigated. Findings: According to the results, the roughness parameters Rz and Ra in the cut length of 0.8 and 2.5 respectively are suitable parameters to estimate the roughness of the inner surface of the fiberglass tube. Also, the roughness of the inner surface of biaxial tubes is lower than uniaxial tubes. In addition, in comparing the roughness of newly produced and old fiberglass pipes, the surface roughness parameters decrease due to the passage of time and the use in projects. Whereas, the roughness parameters related to the type of pipe have not changed. Conclusion: Based on the results of the Surftest SJ-210 device has best results with accuracy of the roughness height reported for fiberglass pipes is equal to 98.84%. In U-PVC, similar to fiberglass pipe, the average roughness values has been estimated with high accuracy using the Ra with a cutting length of 2.5.

Keywords

• surface roughness measuring devices
• glass reinforced plastic pipe (grp)
• roughness parameters
• sandpaper
• u-pvc pipe