Understanding Seal Sections and the Phantom Failures

Abstract Seal/protector sections can be difficult to understand and properly apply. The components in seal/protector sections can fail for reasons that are not fully understood or obvious. Typically, the driving factor for seal/protector section application is temperature (thermal) cycles. Some advocate the use of more mechanical shaft seals, while others advocate parallel chamber configurations, allowing for more expansion/contraction. The question is, "What is the correct approach to take for seal/protector selection?" This paper will attempt to address some of these issues, and focus on seal/protector section failures and areas for improvement. This paper will also give an overall explanation of how seal/protector sections should work and the problems that are often encountered. A current practice in the industry is to apply tandem seal/protector sections as a method of redundancy and in theory, increasing reliability. Advanced materials developed for the harsh temperature environments may be helpful in adapting a single seal section capable of providing superior motor protection in comparison to tandem seals.