Applicant: NORDITUBE TECH SE [BE]
Inventor(s): Fabrice Pirotte [BE]; Lysiane Goossens [BE]; Loïc Meinertzhagen [BE]; Gregory Boheur [BE]
Patent number: WO2025016883A1
Publication date: 2025-01-23
The current invention pertains to a method for upgrading a metal pipe, specifically an urban heating pipe, which includes a jacket made of a tubular sheath or a combination of a tubular sheath and calibration. Additionally, the invention includes a kit designed for retrofitting a metal pipe, along with its application and a refurbished metal pipe.
The problem
Metal pipes, especially those used for district heating, are frequently buried and insulated, making them susceptible to rapid damage from the hot and humid conditions that encourage corrosion. When these pipes are compromised, repairing or replacing them can be a lengthy and costly process. For instance, replacing a pipe often necessitates digging a trench to install a new one. Besides the significant expenses involved, such work can lead to various issues, including road closures, noise pollution, and extended network downtime. Additionally, only small sections of the pipes can be replaced at a time. Alternatively, pipes can be repaired using various techniques that involve inserting tubular lining materials within the existing pipe. These materials are typically treated with a resin that can be cured using radiation or ultrasound, as outlined in documents like WO 9220504 A1, U.S. Pat. No. 4,581,247, and U.S. Pat. No. 4,680,066. Alongside the renovation of district heating pipes, there is also a pressing need to enhance their thermal insulation.
The solution
To address the high expenses and various inconveniences (such as road closures, noise pollution, and extended network outages) associated with replacing metal pipes, the current invention introduces a more straightforward approach by installing a jacket within the pipe. This jacket consists of at least one tubular sheath infused with a curable resin, or a combination of a tubular sheath and a calibration sheath also infused with a curable resin.
Advantages
One goal of this invention is to introduce a method that is straightforward, quick, and cost-effective for retrofitting metal pipes, especially district heating pipes. This method aims to create a coating that not only renovates but also enhances the thermal insulation of these pipes. Additionally, the invention seeks to offer a retrofit kit that facilitates the easy application of this method.
The proposed renovation process for the pipe can be executed using either a reversion insertion method or a translation insertion method. When the liner is inserted into the pipe using either technique, it demonstrates resilience against the roughness and imperfections of the pipe's interior, including corrosion. It also withstands puncturing during the swelling phase or when subjected to air pressure against the wall.