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表观粘度是多级发动机油的重要指标。重点考察了温度偏差和转子转速偏差对冷启动模拟机测定发动机油表观粘度的影响。温度偏差对表观粘度的测定结果影响较大,而转子转速偏差的影响轻微。 相似文献
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通过对车用发动机油低温泵送性能测试方法变化过程的分析,指出发动机在用油低温泵送性分析的必要性,论述了发动机油低温泵送性及其保持性的影响因素,适当的基础油精制深度、合适的粘度指数改进剂类型、长效降凝剂的优选是保证低温性能保持性的前提,发动机油的混用对油品低温性能影响较大。 相似文献
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P. Hutchinson C.D. Neveu R. Cocks 《润滑油》2005,20(3):20-26
Introduction TheviscosityclassificationJ300fromtheSociety ofAutomotiveEngineers(SAE)isusedalmostuni versallytoascribeaviscositygradetoengineoils[1].Thelowtemperaturerequirementsincludedinthis classificationhavebeenrefinedinordertobetterpro tectenginesoperatingunderlowtemperaturecondi tions.Thebasicobjectiveistoensurethattheoilwill flowiftheenginestarts[2].Followinglowtemperaturelubricationfailuresin thefieldinthe70’sand80’s,newlowtemperature requirementswereintroducedintoSAEJ300.These u… 相似文献
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Shear stability of styrene, dodecyl methacrylate, and octadecyl methacrylate terpolymer of various molecular weights, as the rheology modifier of improved solubility, thermal and oxidation stability in mineral base oil, was investigated. Viscosity loss of the 5 wt% solutions caused by scission of macromolecules subjected to the high shear forces ranges between 15% and 27% for weight average molecular weights from 156000 to 252000. After the shear tests the number average molecular weights of polymer increases while weight and Z-average molecular weights decrease. As macromolecules of molecular weights above 700000 fully break the molar-mass dispersity decreases significantly, from starting at 2.34–2.79 down to below 1.8. A linear dependence between viscosity loss of terpolymer solutions and molecular weights was observed. The advantage of using the size exclusion chromatography to determine the stability of the polymer against mechanical shear directly and the viscosity loss indirectly was established. 相似文献
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以十二烷基磺酸钠、甲醛、丙烯酰胺、马来酸酐为原料,通过缩合反应、接枝共聚、金属络合与磺化处理,室内合成了新型的水基钻井液处理剂JN-1。并对其进行室内钻井液性能评价,结果表明,0.5%的该降粘降滤失剂可使淡水膨润土基浆的表观粘度下降42%,API滤失量下降49%,动切力下降80%;可抗NaCl达5%,可抗CaCl2达1.0%;在室温-200℃下24hD态老化试验中,该降粘降滤失剂的抗温性能均较优。 相似文献
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深井油基钻井液在高温高压下表观粘度和密度的快速预测方法 总被引:3,自引:1,他引:2
深井油基钻井液在应用中一个重要的技术难题是如何对高温高压条件下不同井深处的油基钻井液流变参数和钻井液密度进行准确的预测,从而采取相应的技术措施,使之具有良好的携岩能力,并使钻井液密度始终保持在适宜范围。在前人工作基础上,通过对试验数据进行多元回归数学处理,分别建立了预测高温高压下油基钻井液表观粘度和密度的数学模型,并提出了相应的快速预测方法。室内试验结果表明,表观粘度的预测值与实测值的吻合情况良好,相对误差可控制在±10%以内。对钻井液密度预测值的验证有待于今后进行。 相似文献