Henkel (Düsseldorf, Germany) reported on July 16 that its composites repair system for steel pipes and pipelines, Loctite Composite Repair System, has been certified by DNV GL to the global quality standard ISO/TS 24817. It defines the design, installation, test and inspection criteria for the use of composite repair systems for oil and gas pipelines and pipework carrying petrochemical media.
Because the steel shell in a steel pipe is constantly exposed, externally or internally, to the combined corrosive effects of climate factors, mechanical stress and chemical attack, pipeline operators habitually have to deal with cracks, holes, fractures and leaks. In the past, it was common practice to completely replace the affected sections of pipework. However, as this always involves a transport stoppage, maintenance and repair organizations are increasingly switching to repair systems as fast and economical alternatives that do not interrupt operations.
The Loctite Composite Repair System certified according to ISO/TS 24817 is suitable to repair Type A (non-through wall) as well as Type B (through wall) defects, covering all repair classes 1-3. In addition to straight pipes, other components like bends, tees, reducers or flanges can be repaired.
The first step in the repair procedure is to clean and sandblast the surface in the repair area. Since blasted metal surfaces are susceptible to flash rust, Henkel recommends applying the corrosion inhibitor Loctite SF 7515 as a surface treatment, providing temporary protection. In case of Type A defects, the original outer pipe diameter needs to be restored by filling the cavities with Loctite EA 3478. The pipe is then wrapped with high-strength glass/carbon fiber tape Loctite 5085 that has been impregnated with the temperature-resistant, two- part epoxy resin Loctite PC 7210. This adhesive has been specifically engineered for bonding to steel substrates and exhibits good adhesion. The repaired section is then sealed with the sprayable ceramic topcoat Loctite PC 7255. The composite repair system thus reinforces steel pipes for continued duty under high pressure and thermal cycling while increasing their chemical resistance.
Corroded pipes can be repaired in situ, without any interruption in operations and even with high internal pressure, thus avoiding stoppages and commercial losses. Moreover, the quality achieved by the repair can increase the lifetime of steel pipelines by up to 20 years.
As part of the solution package Henkel is also offering calculations of the project-specific repair designs. They differ from project to project depending on a range of parameters such as the forces acting on the pipeline, temperature, pressure and the extent of damage. To maximize safety and efficiency, Henkel has developed a software tool to calculate exactly how the repair should be executed. Henkel has also had this calculation tool certified by DNV GL.
To ensure that the repair system will be properly applied at all times in practice, companies and technicians who are to perform such work must undergo training by Henkel. This is specified in the ISO certification and required by DNV GL. Henkel has therefore developed a tailor-made training program to meet these requirements.
In addition to providing their staff with a certified training, applicants can also have their full operations validated by Henkel. Certification is based on passing an audit that Henkel conducts at the respective firm's premises. The audit focuses not only on the workshop and equipment, but also on health and safety in the workplace, waste management levels, and the knowledge and skills of the employees.