【国外标准】 Standard Practice for Laser Technologies for Measurement of Cross-Sectional Shape of Pipeline and Conduit by Non-Rotating Laser Projector, Infrared Measurement, and CCTV Camera System

4.1 Laser profiling assessment is a quality control tool for identifying and quantifying deformation, physical damage, and other pipe anomalies after installation, providing means and methods for determining the quality of workmanship and compliance with project specifications. Laser profiling can be used for:4.1.1 Measurement of the structural shape, cross sectional area and defects;4.1.2 Collection of data needed for pipe rehabilitation or replacement design; and4.1.3 Post rehabilitation, replacement or new construction workmanship verification.4.2 A laser profile pre-acceptance and condition assessment survey provides significant information in a clear and concise manner, including but not limited to graphs and still frame digital images of pipe condition prior to acceptance, thereby providing objective data on the installed quality and percentage ovality, deformation, deflection or deviation, that is often not possible from an inspection by either a mandrel or CCTV only survey.1.1 Laser profiling is a non-contact inspection method used to create a pipe wall profile and internal measurement using a standard CCTV pipe inspection system, 360 degree laser light projector, a measurement by means of infrared sensors and geometrical profiling software. This practice covers the procedure for the measurement to determine any deviation of the internal surface of installed pipe compared to the design. The measurements may be used to verify that the installation has met design requirements for acceptance or to collect data that will facilitate an assessment of the condition of pipe or conduit due to structural deviations or deterioration. This standard practice provides minimum requirements on means and methods for laser profiling to meet the needs of engineers, contractors, owners, regulatory agencies, and financing institutions.1.2 This practice applies to all types of pipe material, all types of construction, and pipe shapes.1.3 This practice applies to depressurized and gravity flow storm sewers, drains, sanitary sewers, and combined sewers with diameters from 6 in. to 72 in. (150 mm and 1800 mm).1.4 This standard does not include all aspects of pipe inspection, such as joint gaps, soil/water infiltration in joints, cracks, holes, surface damage, repairs, corrosion, and structural problems associated with these conditions.1.5 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.6 The profiling process may require physical access to lines, entry manholes, and operations along roadways that may include safety hazards.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. There are no safety hazards specifically, however, associated with the use of the laser ring profiler specified (listed and labeled as specified in 1.3).1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.