氯化钙溶液环境下单螺杆泵定子材料的损伤研究

Research on degradation of single screw pump stator material in calcium chloride solution environments

单螺杆泵定子材料的损伤对单螺杆泵的使用寿命至关重要。本文以单螺杆泵定子常用材料丁腈橡胶(NBR)为对象,研究其浸泡在不同浓度氯化钙(CaCl_(2))溶液环境下的损伤情况。采用拉伸试验和Shore A硬度研究NBR的机械性能变化,采用重量损失法研究NBR的重量损失情况,采用衰减全反射傅里叶变换红外光谱技术(ATR-FTIR)对老化试样表面的化学变化进行研究。试验结果表明,老化时间和CaCl_(2)溶液浓度对其机械性能的损伤有直接的影响。NBR在CaCl_(2)溶液中质量变化明显降低。ATR-FTIR试验结果表明,在CaCl_(2)溶液环境下,试样表面的分子结构随着老化时间以及CaCl_(2)溶液浓度的增加发生了明显的变化,材料损伤主要表现在分子链的氧化、酰胺的水解和Cl-的卤代反应。

The degradation of single screw pump stator material is critical to the service life of a single screw pump.Nitrile butadiene rubber(NBR),a common material of a single screw pump stator,is used to study the degradation of NBR specimen exposed to calcium chloride(CaCl_(2))solution of different concentrations.The changes in mechanical properties of NBR specimens are studied by tensile test and shore A hardness test.The weight loss of NBR specimens in different concentrations of CaCl_(2)solution environments is studied experimentally.ATR-FTIR spectroscopy is used to study the surface chemistry change of the aged NBR specimen.The results show that exposure time and concentration of CaCl_(2)solution directly affect the degradation of mechanical properties.The mass variation of NBR specimens in CaCl_(2)solution decreases significantly.The ATR-FTIR test results demonstrate that with the increase of exposure time and concentration of CaCl_(2)solution,the molecular structure of the specimen surface changes significantly.The material degradation is mainly manifested in the oxidation of molecular chains,the hydrolysis of amides,and the halogen reaction of Cl-.