Ductile Iron Pipe Restrained Joints – Basics and Design

The rubber gasket inside a Ductile iron (DI) pipe joint will keep it watertight against internal water pressures well above 1,000-psi yet that same gasket provides less than 100-psi worth of longitudinal resistance towards preventing joint separation in shallow or above-ground assemblies, hence the need for joints restrained by some additional mechanism.  This presentation outlines how and why this occurs, through discussion of the forces, features, and functions of restrained joint DI pipe.  Concepts addressed in this session include:

  • The “math of force” related to internal water pressure in the pipeline, 
  • comparing working pressure, design pressure, test pressure, and pressure rating, 
  • old-fashioned thrust blocks vs. modern restrained joint pipe, 
  • calculating restrained joints requirements quickly and accurately, 
  • ductile iron restrained joint pipe assembly procedures, and 
  • the use of segmented restraining gaskets and/or wedge-action retainer glands. 

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Presentation Duration: can be tailored from 30 to 45 minutes at the clients’ request. 

Available Presenters: McWane Ductile Regional Sales Engineers, Product Engineers and select local Sales Representatives.  Details provided upon scheduling of a Training Session. 

Prior Presentation Locations: Contact your local McWane Ductile Sales Representative to determine which locations we can provide this presentation. CEU / PDH / TCH professional development hours available in select locations. 

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