Empowering gas sector optimization and expertise

A joint venture of Fluxys Europe BV and GRTgaz Développement, C4Gas SAS is a common sourcing platform for multiple gas companies, designed to optimize technical specifications and equipment supply for the construction and maintenance of gas networks.

Together, we draw on shared expertise to inform smarter buying for the gas sector. Created in 2002 in Brussels, we moved to Paris in 2006, to bring specialist know-how to the buying chain for gas equipment like pipes, fittings, valves and flanges, along with related technical expertise for gas network operators.

Our unique positioning as a link between clients and suppliers enables us to provide value-added services, designed for the European and international gas industries. As a cooperative, we work better together, for gas transportation.


Fluxys is the Belgium's independent operator of the high-pressure natural gas transmission network, the natural gas storage infrastructure and the liquefied natural gas (LNG) terminal in Zeebrugge.

As a Fluxys group company it is his mission to contribute to a sustainable energy future and passionate teams secure reliable and affordable energy flows into the market.

GRTgaz is a major operator in the high-pressure gas transportation sector. The company has a public service mission aimed at guaranteeing the continuity of gas transmission, and a genuine commitment to promoting renewable gas and to the energy transition in the territories.

What we do best

We have our own technical specifications for materials and coating, ready to be adapted and personalized to each client's needs. Our transparent and rigorous processes facilitate supplier qualification and follow-up by site or production line. Everything we do, is carried out with respect to industry standards*.

From call for tender to final signature, our buyers clearly contractualise everything for our clients, making sure that you know where you are, every step of the way.

* Standards / Normes : Pipe : EN ISO 3183:2012 - Coating : EN 10301 ISO 15741 – Flange : EN 1759-1:2004 - Fitting : EN 14870-2:2004 - Valve : EN 14141:2013 + EN 13942:2009

Technical specifications General Terms & Conditions

A shared set of technical procedures and specifications, as well as transparent

Mills qualification

A commonly agreed system for qualification, coupled with meticulous supplier database management.


Constant landscape monitoring for new suppliers, with careful contact research to ensure a perfect fit.

Business services

Precise and detailed opportunity studies to provide Europe-wide support for companies.

Market vigilance

Stock market monitoring combined with thorough market research, to create a bespoke client sourcing strategy.


Stringent need gathering and analysis for both framework contract tenders and ad hoc calls for tender.

Contact us


Technical Manager: Mr Thierry KERZERHO

Sourcing Manager: Mrs Alice SOU, Mrs Justine DUMAS

Support: Mrs Marine GUILLEVIC, Mrs Marie ROBADEY

24 rue de la Pépinière - 75008 PARIS France



+33 (0) 1 42 94 04 99

Our new website is under construction, this current version is a temporary one.