ABSTRACT
As composite repairs continue to be utilized more frequently, the knowledge-base of the composite manufacturers, installers and the end users has continued to increase as well. The information to be discussed looks to address the “best practices” of the industry by briefly examining each major step within the repair process and highlighting key aspects that are often overlooked or not considered important. Intended for both composite repair novices and industry experts, this paper is split into three primary categories - design, installation and inspection.
The design portion in this paper discusses key concerns prior to installation and includes topics such as choosing the right material for the repair application and having proper repair documentation. The next major topic of discussion is regarding the installation process. When a repair underperforms expectations, the initial responsibility tends to fall on the repair installer. This focus on the installer will be re-examined throughout this paper by looking at deficiencies in training methods and supporting installation documents. Lastly, key points with regards to the inspection process will be addressed, such as types of defects to look for and what constitutes as an unacceptable defect.
INTRODUCTION
Composite repairs are becoming much more common-use and accepted as a viable and tested option to supplement steel sleeves, cut-outs and other more traditional repair technologies. The intention of this paper is to help the end-user, operators, installers and manufacturers learn some of the key aspects that need to be considered when using a composite repair. Split into three primary sections, the first and largest section will investigate design considerations while the following sections discuss key points during the installation and inspection processes.
The objective of this paper is not to provide a simplified “how-to” instructional guide but rather will bring up and address key considerations in all steps to help set the bar for an industry minimum. Current standards, such as the ASME(1) PCC-21 and ISO(2) 24817,2 do well at setting a minimum starting point for composite repairs and providing a fairly detailed testing requirement for a system to be used. This paper will not go into detail with regards to ensuring a minimum test requirement for materials beyond stating that all materials should meet the minimum of the two mentioned standards. These materials should be able to demonstrate additional testing and engineering prudence for any unique scenarios not explicitly covered by the standards. Additionally, this paper must assume that all testing and provided literature from a manufacturer are accurate and have been verified. It will always be up to the end-user to determine if the material provider and composite designer are providing reliable test data and have a complete understanding of the materials they are proposing. Many material providers build creditability for their products by having the materials tested or witnessed by a 3rd party company.
