Over the last five years, Trelleborg has undertaken substantial research into the production and testing of rubber fenders, highlighting concerns with industry practices and making recommendations for change and improvement.
This awareness campaign has been successful in terms of driving the issue of rubber fender quality. As a result, we are starting to see the industry’s perception of rubber fenders move from being commodity products, to a more in depth understanding of the specialized, engineered solutions required.
The rich history of foam
First produced 35 years ago, foam fenders are versatile products that are used in numerous challenging applications. They provide a tough, heavy-duty fender solution for harbor, off-shore and ship-to-ship applications. Their resilient foam-filled construction provides an unsinkable fender body that permits high energy absorption with relatively low reaction force.
Foam fenders are used in many demanding applications, and as such, a deep understanding of the performance of the fender is vital. Unfortunately, performance testing and data reporting for foam fenders is not well understood across the industry and worse, can potentially be misleading. Insufficient research has been conducted into foam fender performance, although there have been numerous upgrades to foam as a raw material since the first foam fender was introduced.
In this paper, we investigate the foam material itself, and its behavior under high compression. This enables us to understand the real behavior of foam fenders and, recommend a test for quality assurance of foam fenders. So, before we delve into testing procedures for foam fenders, we will begin by examining foam itself, the most vital component of the fender.
However, foam fenders are still seen to be something of a commodity product. Solutions that can be bought ‘off the shelf’ to be installed quickly when needed. Until now, there has been a lack of standards to guide the development of foam fenders, and no guidelines on testing them. Trelleborg believes that this absence of a definitive protocol for the specification, manufacture and testing of foam fenders is playing a part in the erroneous perception that they can be so easily bought and deployed.