NEUMAG丝桶往复装置常见故障及原因

介绍了NEUMAG丝桶往复装置的主要组成结构及常见故障。根据实际生产经验分析故障原因并提出处理常见故障的方法。提出日常维护保养方法及注意事项。     

SHL20-13-A型锅炉节能综合改造

介绍了在20t/h正转链条炉排锅炉上的多项实用型节能技术成果。     

HV481丝筒往复装置的几种常见故障

本文对HV481丝筒往复装置的工艺流程进行了简单介绍，主要讨论了几个难点故障的成因及其解决方法。     

压裂泵往复密封性能及机理研究

根据流体动压润滑理论，对压裂泵柱塞密封摩擦副的润滑机理进行了理论分析。在排出和吸入行程，柱塞密封摩擦副均能满足流体动压润滑的条件，即在柱塞与密封界面上能形成并保持一定厚度的油膜润滑密封，从而达到减小摩擦提高寿命的目的；建立了摩擦界面油膜厚度和泄漏量的计算公式。利用有限元法理论，对密封圈的压力沿轴向的分布规律、泄漏量与压力变化关系进行了模拟计算。对往复密封圈沿轴向压力分布、泄漏量随压力变化进行了测试；试验结果表明，建立的计算模型具有较高的计算精度，揭示了压裂泵的密封机理。     

链条炉及其设备常见故障的处理和预防

根据锅炉运行实际，归纳介绍了工业锅炉链条炉炉排拒动、主动轮磨损破裂、风机振动、风机漏油、螺旋除渣机卡住故障的简易快速处理技巧和防止措施，有较强的实用价值。     

提高采用环状阀的立式往复真空泵真空度的方法

本文对采用自动固定气阀的立式往复式真空泵真空度的影响因素进行了理论分析，并介绍了设计ＬＶＰ－１００型立式单缸双作用无油泣滑往复真空泵在提高真空度方面所采取的措施，以及在制造样机过程中提高真空度所作的一些改进方法。     

Surface nanocrystallization of 7A04 aluminium alloy induced by circulation rolling plastic deformation

The surface nanocrystalline microstructures of 7A04 aluminium alloy was obtained by means of circulation rolling plastic deformation（CRPD）, the grain refinement behavior and the hardness variation were examined. X-ray diffraction（XRD） and transmission electron microscopy（TEM） were applied to characterize the microstructure of the surface layer. The experimental evidences show that, after the CRPD treatment, the mean grain size in the surface layer is about 50 nm. The microhardness of the nanostructured surface layers is enhanced significantly after CRPD compared with that of the matrix, which can be attributed primarily to the grain refinement. The microhardness at the top surface can reach about HV0.05335, while the value of the matrix is HV0.05160 or so. The surface hardening effect is obtained obviously. Besides, the thermal stability of nanocrystalline layer was investigated. The results of the XRD analysis and the microhardness measurement show that the nanocrystalline layer has better thermal-stability than the matrix. And the DSC measurement shows that the synthesis of nanostructured surface layer has influence on the phase transformation of 7A04 aluminum alloy.