What is ISO 21857 about?
ISO 21857 establishes the general principles for the evaluation and minimization of the effects of stray current corrosion on external surfaces of buried or immersed pipeline systems caused by AC and DC electrical interference.
Other stray current effects such as overheating and interference with welding operations are not covered in this document. A brief description of AC effects, general principles and some guidelines, are provided.
Systems that can also be affected by stray currents include buried or immersed metal structures such as the following:
- Pipeline systems
- Metal-sheathed cables
- Tanks and vessels
- Earthing systems
- Steel reinforcement in concrete
- Sheet steel piling
ISO 21857 can also be used for pipeline systems outside of the petrochemical and natural gas industries and other buried or immersed structures.
Who is ISO 21857 for?
ISO 21857 on prevention of corrosion on pipeline systems is relevant to:
- Manufacturer of metal pipes
- Electrical engineer
- Petrochemical and natural gas industries
- Manufacturer of tanks and vessels
- Manufacturer of metal-sheathed cable
Why should you use ISO 21857?
Stray currents cause metal loss due to electrolysis, this results in corrosion of metal that is buried or immersed underground.
ISO 21857 provides guidelines for the design of cathodic protection systems that might produce stray currents, design of pipeline systems, or elements of pipeline systems, which are buried or immersed, and which can be subject to stray current corrosion, and the selection of appropriate protection or mitigation measures. Internal corrosion risks from stray currents are not dealt with in detail in ISO 21857 but principles and measures described here can be applied for minimizing the interference effects.
As the user of ISO 21857, you can be ensured of durable, corrosion-resistant buried or immersed underground pipeline systems that minimize the risk of leakage and contamination. As a result, ISO 21857 takes into account the safety and protection of the product end-user while also prolonging the service life of the system. Overall, with ISO 21857, you will be able to scale your business with globally accepted guidelines.
