Low-temperature characteristicsof rubbers and performance testsof type 120 emergencyvalve diaphragms

Purpose–The type 120 emergency valve is an essential braking component of railway freight trains,butcorresponding diaphragms consisting of natural rubber(NR)and chloroprene rubber(CR)exhibit insufficientaging resistance and low-temperature resistance,respectively.In order to develop type 120 emergency valverubber diaphragms with long-life and high-performance,low-temperatureresistant CR and NR were processed.Design/methodology/approach–The physical properties of the low-temperature-resistant CR and NRwere tested by low-temperature stretching,dynamic mechanical analysis,differential scanning calorimetryand thermogravimetric analysis.Single-valve and single-vehicle tests of type 120 emergency valves werecarried out for emergency diaphragms consisting of NR and CR.Findings–The low-temperature-resistant CR and NR exhibited excellent physical properties.The elasticityand low-temperature resistance of NR were superior to those of CR,whereas the mechanical properties of thetwo rubbers were similar in the temperature range of 0℃–150℃.The NR and CR emergency diaphragms metthe requirements of the single-valve test.In the low-temperature single-vehicle test,only the low-temperaturesensitivity test of the NR emergency diaphragm met the requirements.Originality/value–The innovation of this study is that it provides valuable data and experience for futuredevelopment of type 120 valve rubber diaphragms.

鄂尔多斯盆地J县西南部地区延9和延10油层组储层特征研究

通过对鄂尔多斯盆地J县西南部地区延安组延9、延10油层组砂岩岩矿特征分析表明:砂岩主要为长石砂岩和岩屑质长石砂岩;岩屑以沉积岩岩屑为主;砂岩中填隙物总含量相对较少,各填隙物含量之间存在差异,主要以泥质杂基和胶结物为主,胶结物中方解石含量最高。扫描电镜及铸体薄片分析表明,该区砂岩主要孔隙类型为粒间孔及粒内溶蚀孔隙。根据压汞参数分析,区内砂岩储集层孔隙结构具有较强非均质性,为中低孔、中渗储层。