Julian West
Papers # 2016 Berlin
Until the late 1950’s water and sewerage pipe lines used predominantly ridged joints often made from tared yard and cement mortar. The introduction of ‘flexible’ rubber ring joints in the 1960’s allowed, angular deflection, transverse shear load and localized pipe deformation without leakage or failure of the joint.
The main criteria for the development of pipe joints are:
- Leak tightness from both infiltration and exfiltration
- Ease and reliability of jointing on site
- Long term durability
This paper considers each criteria and presents a brief history of elastomeric seals in water and sewerage pipeline systems looking at how the existing materials and designs of joints has evolved. It considers the current material standards and how these specifications relate to the long term durability of the joint. Physical and chemical stress relaxation using ISO methodology to predict the service life of the elastomer is presented. Practical considerations in joint design to reduce or even eliminate potential site mistakes during installation are discussed. The use and advantages of non-linear finite element analysis in seal and joint design is presented.
