Advances in Inspectability & Validation of Non-Metallic Composite Repair Systems

Introduction

In recent years, the growing use of composite repair systems for the rehabilitation of piping systems in the refining and chemical industries has increased the need for associated technologies for their manufacturing, installation, and inspection. One critical aspect of these repair systems is how to inspect and validate them for fitness for service. Until recently, the inspection and validation methods have been based on visual and subjective techniques. Existing radiographic technology has been demonstrated to provide proper validation and quality assurance, allowing a full fitness-for-service program to be implemented, which could indefinitely extend the service life of a composite repair.

This article covers the testing completed for fiberglass and carbon fiber composite repair systems with specialty epoxy for full inspection capabilities. 

Background

Fiber-reinforced polymer (FRP) systems are widely utilized in the reinforcement of infrastructure, including steel piping, in the oil and gas industry. With design standards of these systems in place from ASME and ISO, the acceptance of composite systems as a reliable and cost-effective repair method continues to increase. Inspection methods of these types of repairs, however, are very limited, with codes referring to the repair system supplier for guidance on methods of inspection.