The impact of metal cleaning agents on components of air conditioning piping systems in EMUs

Abstract

Purpose-In response to the problems of performance degradation, sealing failure and medium leakage of metal components in air conditioning pipelines due to material corrosion, this study intends to lay the foundation for exploring the causes of corrosion and optimising anti-corrosion measures in the future, ensuring the safe and stable operation of air conditioning pipelines.

Design/methodology/approach-Systematic investigation of corrosion mechanisms and cleaning agent effects was conducted using scanning electron microscopy (SEM), atomic force microscopy, corrosive element detection and cleaning agent immersion tests.

Findings-Findings indicate dense corrosion pitting on the tail surface of air conditioning copper tubes (TP2 deoxidised copper), with enriched corrosive Cl and P elements serving as primary corrosion drivers. Under continuous immersion, metal corrosion rates significantly exceed air exposure conditions. Both acidic and alkaline cleaning agents exhibit stronger corrosive effects on carbon steel pressure sections and copper tubes than neutral cleaning agents.

Originality/value-The main factors causing corrosion of TP2 deoxygenated copper pipes in air conditioning, the effects of different environments, and types of cleaning agents on the corrosion of pipeline metals have been identified in the study. It provides reliable theoretical support for the optimisation of anti-corrosion design and scientific selection of cleaning agents for air conditioning pipelines.

Keywords

Metal cleaning agents / EMU / Air conditioning piping system / Corrosion

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