Doc. 48 - Elastomeric Seals

The Guideline Elastomeric Seals addresses hygienic aspects of elastomeric seals in food processing and packaging components. It discusses those attributes of elastomers which are important for seal effectiveness and it presents basic design principles for the interfaces between seals and product contact surfaces.
A practical guide to failure analysis and seal handling completes the document.

Contents

1 Objectives and scope
2 Definition of Terms
3 General Considerations
4 Special Considerations  
5 Basic Design Principles
5.1 Choice of Materials
5.2 Surface Quality
5.2.1 Surfaces in contact with seals  
5.2.2 Surfaces of Elastomeric Seals  
5.3 Compression
5.3.1 Constancy of Volume
5.3.2 Effect of Hardness  
5.3.3 Surface Damage due to Friction
5.4 Groove Fill
5.5 Alignment  
5.6 Avoidance of Crevices
6 The Behaviour of Elastomers used as Seals
6.1 Effects of Temperature  
6.1.1 Aging  
6.1.2 Thermal Expansion.
6.1.3 Temperature Cycling  
6.2 Effects of Pressure
6.3 Effects of Mechanical Stress
6.4 Effects of Media  
7 Hardware Design  
8 Troubleshooting
8.1 Examples of seal damage  
8.2 Failure Documentation
9 Handling of Seals
9.1 Packaging  
9.2 Storage  
10 Legislation
10.1 Documentation  
10.2 Traceability  
10.3 Marking  
11 Technical Information about the Material of the Seals which should be provided by Suppliers
12 References