COMBINED PHOTOGRAMMETRY AND 3-D CAD FOR PLANT DOCUMENTATION AND PLANNING OF REFITS

Meticulous advance planning and erection studies using a three-dimensional computer-aided design model of the plant area concerned can reduce the problem that unexpected events during a plant refit will prolong the required inspection period. This presupposes that a 3-D CAD scale model of the running plant has been generated. A method is described with which the as-built condition of the plant area is converted into a 3-D CAD model by combining photogrammetry with 3-D CAD. The minimum amount of time required for in-plant surveying and the completeness and clarity of results are the special advantages of this method in comparison with other measurement techniques. Selected applications are presented.