DUCTILE IRON FITTINGS - ACCESSORIES - RUBBER GASKET
Why SBR/EPDM gaskets are used in place
of NR
Rubber Gaskets have been
used in metallic / non metallic pipes for more than a century in Europe and some of these
pipelines are still working with joints giving continuous effective service. Initially all
rubber gaskets were manufactured from Natural rubber. But later it was found , that the
presence of protein in Natural rubber attracts white ants and apart from that
micro-biological growth also takes place. These action deteriorates the gaskets and the
water quality. In-depth studies were made and different types of Rubbers viz. SBR (Styrene
Butadiene Rubber), EPDM (Ethylene Propylene Diene Rubber), Neoprene (Polychloroprene
Rubber) were developed to suit varied application conditions.
The better efficacy of
the specialized rubbers against different site conditions like higher temperature,
presence of hydrocarbons are time tested and is the basic reason for the prevalent use of
SBR and EPDM gaskets in pipelines. Currently most of the gaskets used in India are SBR
quality and in Europe they are made of EPDM. ECL manufactures both. A qualitative chart is
provided indicating the characteristic advantages of different types of rubbers.
