通过对“管中管”管道的现场调查和室内分析,发现管体腐蚀主要是由保温层内进水致使电化学腐蚀引起的。保温层内进水达到饱和的管体腐蚀较轻,保温层半干不湿的管段腐蚀严重。为解决这一问题,在夹克管内加牺牲阳极能有效地控制腐蚀,此方案已在胶青线实施8年,取得了明显的防腐效果。 Through on-the-spot investigation and indoor analysis of “tube in tube” pipeline, it is found that the corrosion of tube body is mainly caused by the electrochemical corrosion caused by water infiltration in the insulation layer. Insulation layer into the saturated water pipe corrosion lighter, insulation layer half-dry pipe corrosion is not serious. To solve this problem, the sacrificial anode can be effectively controlled in the jacket tube to prevent corrosion. This solution has been applied for 8 years on the gelline and has achieved obvious anti-corrosion effect.