超超临界机组汽轮机油性能评价及其劣化原因分析

Property Assessment and Cause Analysis of Property Deterioration of Turbine Oil for Ultra-supercritical Units

按照GB/T 7596-2017要求考察了超超临界机组在用汽轮机油的理化性能,结果表明使用一年半的汽轮机油除水分、颗粒污染等级和旋转氧弹超标外,其他理化性能满足指标要求,但其抗氧化、抗泡沫、空气释放性和抗乳化性能有劣化的趋势。油中酚类抗氧剂含量降低,导致抗氧化(旋转氧弹)性能劣化。抗氧化性能劣化及水分、污染等级的超标导致抗泡沫、空气释放性和抗乳化性能下降。此外往复运动摩擦磨损(SRV)试验表明,与新油相比,在用汽轮机油摩擦系数不稳定且磨损较大。SEM分析表明,在用汽轮机油试件表面产生明显的犁沟,这是在用油颗粒污染等级较高引起的。EDS元素分析表明在用汽轮机油润滑的试件磨斑表面氧含量较高,其原因为在用油抗氧化性能下降。

The physical and chemical properties of turbine oil currently used in ultra-supercritical units were investigated in accordance with GB/T 7596-2017.The results show that the physical and chemical indicators,except for moisture content,particle contamination level and rotary oxygen bomb,of the turbine oil in use for one and a half years meet the requirements,but its anti-oxidation,anti-foaming,air release,and anti-emulsification properties tend to deteriorate.The decrease of phenolic antioxidant content in the turbine oil leads to the deterioration of the antioxidation(rotary oxygen bomb)property.The deterioration of the antioxidation property and excessive moisture content and contamination level result in the decline of foam resistance,air release,and emulsification properties.In addition,the SRV test shows that the current turbine oil has an unstable friction coefficient and significant wear level,compared with the new turbine oil.The SEM analysis indicates that there are obvious furrows on the surface of test pieces using the current turbine oil,which was caused by the particle contamination level of the current oil.The EDS elemental analysis demonstrates that test pieces lubricated with the current turbine oil have a high surface oxygen content,which was caused by the deterioration of the antioxidation property of the current turbine oil.