Remote Visual Testing (RVT) For Internal Pressure Vessel Inspection

Abstract

Remote visual testing (RVT) of large surface areas (1 sq. meter) associated with vessel inspection requires a unique hardware approach compared to that of commercially-available borescopes, fiberscopes, and video borescopes. Faced with stricter OSHA regulations and the increased global competitiveness of today’s marketplace, process facilities have looked toward a technical solution, including manless entry into vessels, pressure vessels, and tanks for their internal inspections. A unitized pan, tilt, light, color, zoom video inspection system was developed for use in confined space and hazardous area locations associated with these components.

Introduction

Since the early 1970s commercially-available borescopes, fiberscopes, and video borescopes have been successfully applied to a very wide range of industrial inspection tasks including aircraft engines, nuclear steam generators, pharmaceutical tubing, and border crossing contraband detection. As a virtual spin-off of the medical instrument market place, industrial RVT has adopted and modified medical probe technology for suitability in the fast growing commercial sector. However, in the technical transfer of medical hardware to the larger scale applications of petrochemical process units such as pressure vessels, mixers, tanks and steam drums, it became apparent that a scaled-up approach was necessary. Additionally over the past several years, VT/RVT has been professionalized as an official NDT discipline by way of ASNT’s TCIA Level-III testing and certification process and many industrial facilities are dramatically increasing the use of RVT.