How are the material selection and corrosion protection for buried water pipes specified?
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Happy New Year to everyone! I’m in urgent need of help. Our company has installed a new recirculating water cooling tower system, and this system is located in an area subject to hydrochloric acid corrosion. Several large-diameter water pipes (DN500) need to be buried underground; carbon steel pipes from our inventory have been chosen for these pipes. I would like to ask whether it’s necessary to repair the trenches, and how to protect the pipes from corrosion
There is hydrochloric acid corrosion – is carbon steel pipe suitable? It’s best not to cause trouble in the future just to save money in the short term.
Buried steel pipes are protected against corrosion using polyethylene tape as a reinforcing layer; for specific details, refer to \"Anti-corrosion Techniques for Coatings on Petrochemical Equipment and Pipelines\" (SH3022-1999) and \"Technical Standards for Polyethylene Tape Coatings on Steel Pipelines\" (SY/T0414-98).
You can refer to the following three standards: 1. Code for Construction and Acceptance of Water Supply and Drainage Pipelines GB50268－97; 2. SY-T 0413-2002 Technical Standard for Polyethylene Coating of Buried Steel Pipelines; 3. SY-T0447-96 Technical Standard for Epoxy Coal Tar Pitch Coating of Buried Steel Pipelines. All three of these standards are available on the forum. Here are some common epoxy coal tar anti-corrosion coatings and their structures: Anti-corrosion coating grade, Structure, Anti-corrosion thickness. Ordinary grade: Primer – Topcoat – Glass cloth – Two topcoats; 0.4mm. Enhanced grade: Primer – Topcoat – Glass cloth – Topcoat – Glass cloth – Two topcoats; 0.6mm. Extra-enhanced grade: Primer – Topcoat – Glass cloth – Topcoat – Glass cloth – Topcoat – Glass cloth – Two topcoats; 0.8mm. This post was last edited by sunnykrc on 2009-2-5 at 12:02
Thank you, OP! Where can I find these standards?
It is best not to use carbon steel pipes; for underground sections, polyethylene or polyvinyl chloride corrugated pipes can be used, and those reinforced with steel wire should be employed where pressure is present