加氢压缩机二级活塞杆断裂失效分析

对压缩机断裂的二级活塞杆进行了材料的化学成分分析、断口的宏观形貌分析、活塞杆螺纹纵截面金相检查以及金相组织分析,并对活塞杆螺纹冷滚压加工工艺进行了讨论,最后认为造成活塞杆断裂的主要原因是由于螺纹加工时出现齿顶整圈环向微裂纹,投入运行后使之崩裂形成缺口,该缺口成为后来疲劳断裂破坏的疲劳源。     

原料气压缩机4级缸活塞杆断裂原因分析

通过对某燃气有限公司原料机4级缸活塞杆断口表面及夹杂物检查、金相组织及硬度测试、力学性能测试、化学成分分析等技术检测手段进行一系列的原因分析,初步认定为送检活塞杆断口为疲劳断裂,疲劳源位于活塞杆淬硬层表面;实验数据显示,送检活塞杆的淬硬层硬度、基体硬度、基体抗拉强度均低于标准值要求,基体屈服强度仅处于标准值下限,致使活塞杆中部受到弯矩作用与填料发生偏磨,从而萌生磨削裂纹后在拉压交变工作应力作用下发生疲劳断裂。     

使用活塞杆运行总结

1活塞杆疲劳断裂的特点 在变应力下，活塞杆的损坏形式是疲劳断裂。疲劳断裂不同于一般静力断裂，它是损伤到一定程度后，即裂纹扩展到一定程度后，发生的突然断裂，疲劳断裂是与应力循环次数有关的断裂。     

镀铬活塞杆表层裂纹分析与解决

本文分析了伺服作动器活塞杆表层裂纹形成的机理,确定了活塞杆表层裂纹的性质和产生原因,以及裂纹的深度范围。采用具有压应力的爆炸喷涂WC/Co工艺代替电镀硬铬工艺解决活塞杆因深度裂纹而报废的问题,制定了可行的维修方案和技术路线,并确定了维修工序和参数。结果表明,修复的活塞杆满足图样尺寸及技术要求,经综合性能比较及磨合实验验证,WC/Co涂层优于电镀硬铬层。     

压缩机活塞杆断裂原因分析及解决措施

本文针对压缩机活塞杆的断裂原因,分析了其活塞杆的材料组成成分、宏观断口的观察、微观断口的观察、力学的性能和金相显微观察等相关方面,得出压缩机活塞杆的断裂原因是疲劳断裂,即当活塞碎裂后,受到驱动力的挤压,导致弯曲变形,最终形成断裂。     

C302氢压机活塞杆断裂原因分析

通过对活塞杆疲劳断裂原因的理论分析和计算,提出了提高活塞杆预紧段弹性的观点,介绍了防止活塞杆断裂的历次改造过程。     

某型飞机舱盖手动开启机构活塞杆橡胶面开裂失效分析

本文主要对故障活塞杆和配合密封的活门座子进行了外观检查,对活塞杆橡胶面表面以及橡胶断裂断口进行了宏观、微观观察,对活塞杆使用的橡胶进行了红外光谱等分析。综合各个实验结果,确定活塞杆橡胶面裂口起源于活塞杆与橡胶结合的内圆周处,开裂的原因为过载开裂。     

活塞杆表面裂纹的磁粉探伤方法剖析

本文对不同时期的活塞杆产生表面裂纹的原因及特征进行了分析，并对在不同时期采用相应的磁粉探伤方法做了介绍，同时总结了发现表面裂纹后的活塞杆的处理方法。     

3D22（Ⅱ）氮氢气压缩机着火爆炸的原因分析

对3D22（Ⅱ）压缩机由于活塞杆断裂引起着火爆炸的事故进行了分析，并着重分析了活塞杆断裂的原因。     

超硬材料六面顶液压机铰链梁断裂失效分析

通过对超硬材料六面顶液压机铰链梁断口表面进行宏观观察,材料化学分析,力学性能测试,断口扫描电镜观察,能谱分析和显微组织分析,找出了铰链梁的断裂失效原因.综合理化数据分析研究得出结论,超硬材料六面顶液压机铰链梁铸件中的氧化物和硫化物严重夹杂是产生断裂的主要原因,铸件中的缩松、成分偏析、也加速了疲劳和裂纹的扩展,最终使铰链梁断裂.     

船用柴油机活塞杆表面微粒增强镍基复合镀层的制备及其性能分析

采用电沉积方法,在船用柴油机活塞杆表面分别制备纳米微粒增强镍基复合镀层、亚微米微粒增强镍基复合镀层和微米微粒增强镍基复合镀层。分析了三者的显微形貌、晶相结构及磨痕形貌,并测定了硬度。结果表明:与亚微米微粒增强镍基复合镀层和微米微粒增强镍基复合镀层相比,纳米微粒增强镍基复合镀层的外观显得更加光亮,硬度接近5 800 MPa。     

Response of Cavity Pressure to Vibration Parameters During VAIM Process

Summary In this study, a new type of vibration-assisted injection molding machine was introduced including the principle, structure and application. The responses of cavity pressure to the piston rod vibration amplitude and vibration frequency were discussed in detail. The cavity pressure oscillation frequency was the same with the piston rod frequency. The piston rod vibration frequency had little effect on cavity pressure oscillation amplitude. The cavity pressure oscillation amplitude increased with the increase of piston rod amplitude. The introducing of vibration forces field shortened the filling time, postponed the gate-frozen time and quickened the pressure build up process. More materials could be packed into the mold as the mean cavity pressure was higher which improved the quality of the products.     

壳牌气化煤制甲醇二氧化碳压缩机问题分析和改进

介绍了壳牌粉煤气化煤制甲醇二氧化碳压缩装置的设计和装置的运行情况,针对二氧化碳压缩机运行中存在的压缩机辅机及管道震动大、二级缸支承环磨损快、活塞杆活塞紧固螺母处断裂等问题,提出了相应的改进措施,实现了装置的长周期运行,取得了较好的效果。     

关于螺杆式压缩机启动过电流故障分析

某公司生产的RCUA200WHZ-E R410A环保冷媒水冷式冷水机组,其压缩机启动时出现过电流故障。对压缩机拆解后发现:固定活塞与连杆的挡圈结构断裂,机组启动后滑阀不能跟随活塞运动,导致机组带载荷启动,出现启动电流过大报警。利用显微镜观察挡圈断口发现:挡圈断裂是由于加工过程中折弯模具下模V型槽过小,而且折弯部位的压力超过挡圈材料的拉伸强度,产生微小裂纹,并最终在机组运转过程中受力断裂。     

Preparation,characterization, and photocatalytic degradation properties of polyacrylamide/calcium alginate/TiO2 composite film

Titanium dioxide (TiO₂) nanoparticles were dispersed in the sodium alginate and acrylamide aqueous solution to prepare the casting solution. The casting solution was spread on a glass plate by a glass rod enlaced with brass wires to control the thickness of the film. Then polyacrylamide/calcium alginate/TiO₂ (PAM/CA/T) composite film was obtained after UV irradiation and crosslinking by CaCl₂. The PAM/CA/T film was characterized by scanning electron microscopy and transmission electron microscope. The mechanical properties of the films were tested in wet form and the results showed that PAM/CA/T film had good strength and toughness. PAM/CA/T films did not rupture after swelling in 5.0 wt% NaCl solution and still had good mechanical properties. The PAM/CA/T hydrogel film provided a suitable carrier for TiO₂ in the photocatalytic degradation of dyes and the degradation rate of PAM/CA/T‐30 for methyl orange reached 80.8%. The PAM/CA/T film had good reusability and could degrade dyes in a high concentration of NaCl solution. POLYM. COMPOS. 37:1292–1301, 2016. © 2014 Society of Plastics Engineers     

汽轮机调速系统油动机轴封泄漏处理

主要从汽轮机的油动机活塞杆密封形式、密封材料及活塞杆偏斜等方面,分析了义马气化厂空气压缩机组中汽轮机调速系统油动机轴封泄露的原因,通过采用Yx型聚氨酯密封圈作为轴封、双串联方式、并对密封套结构进行改进等措施,较好地解决了轴封泄漏问题,保障了油封系统长周期无泄露运行,提高了汽轮机运行的安全性。     

卧式离心浇铸法生产MC尼龙棒

在模具设计中,通过改变浇铸流道方向,设计制造出一系列不同规格的组合模具,开发了卧式离心浇铸法生产MC尼龙棒的工艺技术,制备了一系列不同规格的旋转棒,并对产品进行了分析测试.结果表明,采用卧式离心浇铸法生产MC尼龙棒是有效可行的,可完全消除MC尼龙棒材中的收缩孔和内部缺陷.卧式离心浇铸法具有生产效率高、产品质量好、成品率...     

基于仿真的硫化机液压系统设计

假定液压硫化机的负载为200 kN,设计的硫化机液压系统合模缸活塞直径和活塞杆直径分别为320和220 mm,上模缸活塞直径和活塞杆直径分别为100和70 mm,压力油管内径为12 mm,吸油管内径为25 mm,油箱容积为160 L.采用液压系统建模与仿真软件AMESim进行额定工况的建模仿真,结果表明,所设计的液压系统具有足够的合模力,达到了设计要求.     

Mechanics of Constant-Rate Filter Pressing of Highly Flocculated Slurries

The growth of a powder compact from a highly flocculated slurry has been simulated by a computer program that models non-steady-state Darcian flow. Computer simulations have been compared with filter-pressing experiments. Constant-rate filter-pressing experiments are divided into two regimes of piston stress—displacement behavior: an initial, almost-linear, but concave-up, regime during cake growth, followed by a second region of rapidly increasing piston stress when the piston comes into contact with the cake. Linear piston stress—displacement behavior is expected, from theory based on a uniform cake model. Highly flocculated slurries show highly nonlinear behavior. Nonlinear behavior is shown to be consistent with nonuniform growth of the cake. The permeability and consolidation behavior of the cake has been determined by a consolidometer experiment. Computer simulations indicate that the particle-packing density profiles during cake build-up are surprisingly similar during cake growth. Conditions for uniform consolidation can be determined from a general equation for non-steady-state Darcian flow. Results are directly applicable to constant-flow-rate pressure casting or slip casting.