The Evolution of a Range of Service Experience Rationalised Sealing Materials Available to Purchase

With the benefit of hindsight some of the initial non-asbestos offerings were doomed to be commercial failures and since then evolution, in the true Darwinian “survival of the fittest” sense, has resulted in the demise of those offerings. In parallel with this process of evolution, the sealing material testing tools that are available have improved. Consequently, the relationship between a material’s contents, its structure, test data and its service potential is far better understood than in previous times. This improved understanding has brought, and will continue to bring, enhanced performance benefits to the end user and increased security against unplanned shut down due to service failures. This paper reviews the evolution process, highlights the classes of materials that have proven to be successful and tries to indicate why, in terms of the properties of the material, they have been successful. The salient features of the content and structure of these materials are also discussed. The paper also speculates about the way in which further consolidation of the range of sealing materials may come about as the process of evolution, driven by cost, performance and environment pressures, continues.