Innovative Technologies Can Help
Aldyl-A pipe, a type of solid wall polyethylene (PE) piping introduced by DuPont in the 1960s and named “Aldyl ‘A'” around 1965, quickly became commonplace in natural gas distribution networks across the United States. However, experience over subsequent decades has revealed that certain vintages of Aldyl-A are prone to brittle-like cracking, also referred to as slow crack growth. This issue has prompted safety concerns, reports of pipe failure and advisories from the Pipeline and Hazardous Materials Safety Administration (PHMSA). Dr. Gene Palermo, in a 2011 white paper on the topic, noted that Aldyl-A’s solid wall PE formulation—enacted by DuPont after phasing out polyacetal blends—became a significant focus in the industry due to these concerns.
As a result, utilities are now required to identify and address Aldyl-A as part of their integrity management programs, with many states and utilities prioritizing the removal and replacement of this pipe due to its vulnerabilities. As utilities seek efficient, low-disruption methods to replace aging Aldyl-A pipes, trenchless technologies have come to the forefront.
The Kobus Pipe Puller is one such innovation, capable of extracting decommissioned pipes while simultaneously pulling in a new pipe, such as PE or copper, along the same bore path. Unlike open-cut replacement, this trenchless process requires only minimal excavations at each end of the pipeline, reducing impacts on roads, landscaping, and surrounding infrastructure. Notably, the Kobus system has already demonstrated success in safely and effectively removing brittle Aldyl-A pipe in other regions, setting a benchmark for how legacy materials can be addressed without major surface disruption.
Key benefits of the Kobus Pipe Puller approach
- Efficiency and Speed: Pipes can often be replaced in hours, not days.
- Safety: The risk of striking adjacent utilities is greatly minimized.
- Reduced Disruption: Minimal excavation helps keep neighborhoods and environments intact.
- Cost-Effectiveness: Reduced site restoration and faster project turnaround lower overall costs.
California’s aging water and wastewater systems are undergoing major upgrades, fueled by public demand, environmental imperatives, and major federal investment. The Biden-Harris Administration’s Bipartisan Infrastructure Law (BIL) and state-level initiatives have unlocked historic funding, over $510 million was announced in 2024 by the EPA alone, much of it to serve disadvantaged communities most impacted by deteriorating infrastructure. These funds are supporting wide-ranging projects, from lead service line replacements to stormwater and drinking water system modernizations. A cornerstone of California’s infrastructure transformation is the transition to advanced PE pipe systems. With federal and state funding driving systematic replacement of legacy materials, PE pipes are rapidly becoming the standard for new installations and upgrades, including replacement of legacy Aldyl-A lines.
Transformative Technologies: Kobus Pipe Pullers and the Way Forward
As states and utilities remove Aldyl-A and similar legacy pipes, the Kobus Pipe Puller is emerging as a practical, proven trenchless alternative that meets today’s demands for safety, efficiency and community sensitivity. By enabling the direct extraction and replacement of brittle, aging Aldyl-A pipe, the Kobus Pipe Puller helps utilities and project managers minimize risk, speed up timelines, and keep control of costs.
With a proven track record with challenging pipes like Aldyl-A, the Kobus Pipe Puller is positioned as an ideal partner for efforts to modernize and safeguard America’s pipeline networks. As infrastructure mandates increase and networks continue to age, solutions like the Kobus Pipe Puller can drive the next wave of safe, smart and sustainable pipe replacements.
