Gas Industry

Gas piping, such as that used in urban distribution networks for a pressure range between 10 and 20 bar, was previously fabricated exclusively from steel. Evonik’s VESTAMID^® LX9030 is now offering a polyamide 12 alternative for this application, one that affords all the cost advantages of plastic over steel and dispenses with the need for expensive corrosion control. Extensive long-term trials over several years have confirmed the stress resistance of VESTAMID^® LX9030 piping and its welded joints. Moreover, the pipes can easily be produced, welded, and installed with standard equipment such as is used for polyethylene piping.

Polyamide replaces steel

VESTAMID^® LX9030, a molding compound specially developed for use in high-pressure gas piping, meets all the safety requirements of the system:

• The material complies with the ISO 22621 and ASTM D2513 or ASTM F2785-09 standards, and the polyamide 12 can therefore be used for gas pressures of up to 20 bar.
• The MRS, at 18 MPa, significantly exceeds the values for the PE used in low- and medium-pressure piping. This makes VESTAMID^® LX9030 an interesting alternative to PE because, for the same pressure load, the wall thickness can be significantly reduced and the internal cross-section for a given external diameter correspondingly increased. This results in a considerable increase in transport capacity. (MRS, the minimum required strength, is the minimum strength required to withstand internal circumferential stress from water at 20°C after 50 years.)
• VESTAMID^® LX9030 has excellent resistance to both slow crack growth, SCG, and rapid crack propagation, RCP.
• In May 2008 TÜV Nord Systems GmbH & Co. KG and SKZ TeConA GmbH approved the use of VESTAMID^® LX9030 specifically for high-pressure gas installations conforming to GasHLVO. The final report emphasizes explicitly that piping systems with PA 12 from Evonik can be operated safely at working pressures of up to 18 bar.

More detailed information is also available directly from our expert.