Style SS – 4″ – 1500 PSI Rated – Super Duplex Coupling and Hardware


SKU: SS0400-C-BTD-D-D Category:


Piedmont Style SS Grooved Coupling With Duplex Hardware

Style SS couplings incorporate the more noble, SUPER-duplex-alloy construction, which although initially more expensive, offers the superior corrosion resistance and corresponding better longevity for highly corrosive environments compared to the Style B coupling which is constructed from 316 alloy.

Super Duplex are produced using a super duplex material, which offers even higher corrosion resistance than duplex, and is very similar to alloys 2507 and Zeron 100 which are commonly used for seawater piping. Made of super duplex stainless steel CE8MN alloy, our couplings are austenitic-ferritic stainless steel and highly resistant to chloride stress corrosion. Super duplex grade of stainless also offers higher strength and better mechanical properties than duplex stainless steel As an option, these couplings can be specified with CE3MN super duplex material, which offers a slightly higher Pitting Resistance Equivalent Number (PREN).

Featured Highlights:

Pressure Rating 1500 psi (103 bar) with schedule 40s pipe (special alloys) with cut groove only – all sizes.

Duplex or SuperDuplex* stainless steel type CE8MN, conform to ASTM A995 Grade 2A. Piedmont also offers this coupling style in CE3MN (Grade 5A) for even higher corrosion resistance

EPDM rubber gasket, suitable for hot and cold water service. NSF/ANSI 61 approved for drinking water system components. Not suitable for petroleum service.

Nuts and bolts are Round-head, square-neck, type 316 stainless steel bolts and heavy hex nuts conform to ASTM F-593 and 594, Group 2, condition CW.

Sizes are 3/4″- 4″ Nominal size pipe.

Duplex Duplex stainless steel is highly resistant to chloride corrosion because of its metallurgy and microstructure. Used for high pressure couplings for seawater installation our duplex alloy is made of two metallurgical phases with each their role to play in the efficiency of the couplings.

Note: Working pressure ratings based upon generally accepted pressure piping design standards and testing in accordance with ASME Section VIII Division 1 pressure vessel test method.


Piedmont Style SS Grooved Coupling Technical Information

Piedmont Style SS Grooved Coupling Product Sheet

Piedmont Style SS Grooved Coupling Technical Drawing

Additional information

Weight 5.86 lbs
Dimensions 5.90 × 7.40 × 2.02 in

Super Duplex

Nominal Size


Gasket Material




Max Pressure (PSI)

1500 psi

Max Pressure (Bar)

82.7 bar

Coupling Style

Style SS Super Duplex (CE8MN)