Pipe made of polyamide 12 (PA12): The right choice for trenchless installation

In recent years pipes of polyamide 12 (PA12) have been thoroughly investigated for high pressure gas installations with operation pressures up to 20 bar (290 psi). After overall positive results from feasibility studies and various test installations, the gas industry followed up with its first service installations under waiver to develop more experience with and confidence in this new material for high pressure distribution lines as an alternative to steel.
To gain additional experience and confidence in the performance of PAI2 pipes installed by alternative installation technologies Evonik investigated the behavior of its PA12 grade VESTAMID® LX9030 if installed trenchless. The authors will summarize the relevant lab test data and will present results of directional drilling and pipe cracking trials performed in Germany. Horizontal directional drilling installation of PA12 in a service installation in Mississippi will be highlighted.

Review of PA 12 high performance thermoplastic material First, as a quick review : PA 12 1s a specialty polyamide manufactured by four companies 1n the world. Due to the specific carbon-amide group in the polymer chain polyamides have strong inter-molecular actions which induce high mechanical strength, high melting temperatures and chemical stability. The “long chain” PA 12 with 11 carbon atoms between carbon-amide groups has the lowest water absorption of all commercial available PA and represents the best compromise in thermal and mechanical properties. That is why PA 12 became the material of choice for some challenging applications e. g. in the automotive industry for fuel lines of passenger cars or for airbrake tubing of trucks and recently also for non-bonded flexible pipes for oil exploration.