This appraisal is for a range of HYMAX GRIP® wide tolerance couplings from DN 40 to DN 300, flanged adapters from DN 80 to DN 300 and end caps in sizes DN 40 to DN 300. The couplings are nominated as PN16 classification. 

The Krausz patented HYMAX GRIP socket is a restrained joint intended for coupling various pipe materials including DI, CI, PE and steel with a wide range of outside diameters. The couplings are not suitable for use with PVC, AC or GRP pipes. The design of the socket consists of a grip chain that offers circular restraint around the pipe thereby avoiding point loads on the pipe surface.

Sealing is accomplished by tightening two top-operated Grade 316 stainless steel fasteners, one on each end of the coupling.  The grip chain is then activated by tightening four additional top-operated bolts, two on each end.

The sealing gasket features a two-layer design whereby the inner layer can be removed to allow larger pipes to be accommodated.

The couplings and flanged adapters are supplied with polymeric coated ductile iron barrels and end rings, except for sizes less than DN 80, which have polymeric cast steel end rings. Grade 316 stainless steel fasteners with an anti-galling compound are utilised. The sealing gaskets are manufactured from EPDM rubber. The flanges are compatible with AS/NZS 4087 PN16.


Product categoryMechanical Couplings - Restrained
PA NumberPA 1702 Issue 2
Report holderKrausz Industries Ltd
StandardEN 14525:2005 Ductile iron wide tolerance couplings and flange adaptors for use with pipes of different materials: ductile iron, Grey iron, Steel, PVC-U, PE, Fibre - cement
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