Twin screw granulation – review of current progress

Twin screw granulation (TSG) is a new process of interest to the pharmaceutical community that can continuously wet granulate powders, doing so at lower liquid concentrations and with better product consistency than found by a high shear batch mixer. A considerable body of research has evolved over the short time since this process was introduced but generally with little comparison of results. A certain degree of confidence has been developed through these studies related to how process variables and many attributes of machinery configuration will affect granulation but some major challenges still lay ahead related to scalability, variations in the processing regimes related to degree of channel fill and the impact of wetting and granulation of complex powder formulations. This review examines the current literature for wet granulation processes studied in twin screw extrusion machinery, summarizing the influences of operational and system parameters affecting granule properties as well as strives to provide some practical observations to newly interested users of the technique.     

The effect of baking time,fillet radius,and hardness on the lifecycles of pole fastening screws in an electric motor with hydrogen embrittlement

In order to protect bolts from corrosion, electroplating such as zinc plating is widely used. However, hydrogen can easily penetrate or diffuse into the vacancies and dislocations between the lattices of bolt steel during electroplating. As the diffused hydrogen defects inside the lattice are in gaseous form, small cracks can easily be produced due to high pressure from the hydrogen gas. In this research, in order to determine the root cause of the fracture in pole fastening screws resulting from hydrogen embrittlement in typical electric motors, additional factors that accelerate hydrogen embrittlement fracture were selectively applied, including a small fillet in the head–shank transition and excessive hardness, and parametric study was performed experimentally.     

XAZ340-4GF反洗压滤机的研制与应用

介绍了XAZ340-4GF反洗压滤机的研制过程,介绍了该机型的结构\原理\工艺系统.并简要介绍了其工业应用情况。     

用于PET薄膜回收的螺杆设计

根据PET薄膜的特点和高分子熔融态流动理论，分析了挤出回收用螺杆的各段结构，及螺杆参数选择，设计出大长径比、深槽、双排气、高效专用螺杆。     

热压/热变形Nd2Fe14B/α-Fe纳米双相永磁体的研究

为了制备各向异性块状Nd2Fe14B／α—Fe纳米双相永磁体，研究了热压／热变形工艺参数与样品微观组织结构、磁性能之间的关系。结果表明，饱和磁化强度Js随模压温度的升高而提高；而剩磁Jr、内禀矫顽力Hcj和最大磁能积(BH)max开始都随模压温度的升高而上升，但超过一定温度后反而降低；同时提高热压压力会使磁性能增加，而热变形温度对磁性能影响很小。热变形后样品垂直于压力方向的磁性能略高于平行于压力方向，呈现出轻微的各向异性。Nd2Fe14B／α—Fe纳米双相永磁材料在热压／热变形后没有产生晶粒的择优长大，在晶体学上仍然是各向同性的。     

河北冶金实验厂8MN快锻液压机电控系统选择

着重阐述了河北冶金实验厂８ＭＮ快锻液压机电控系统的选择过程。经过反复考察，论证，对比，最终所选的压机电控系统为目前国产快锻液压机中自动化水平最高的锻造设备。     

螺杆泵的检测方法及检测标准制定

螺杆泵检测是避免不合格螺杆泵下井、螺杆泵早期失效和提高螺杆泵使用寿命与采油效益的重要技术手段。重点介绍了模拟不同工况的螺杆泵工作特性检测系统及检测定子通径为10－60mm的定子衬套偏心度检测仪的组成及其检测方法和原理。针对大庆油田的实际情况，在进行大量室内和现场试验的基础上，制定了GLB120－27、GLB40－42和GLB500－14型螺杆泵的检测标准。检测技术及其标准实施以来见到了明显效果。     

地面驱动单螺杆泵杆柱的组合设计

根据地面驱动单螺杆泵的工作特点，分析了传递动力的抽油杯柱受力状况，认为抽油杆柱受复合载荷的作用，在承受扭矩的同时承受较大的轴向力，给出了各种载荷的计算方法。由第四强度理论，提出了把抽油杯柱设计成两级杆柱的等强度组合设计方法，即先按要求及标准确定两级杆柱的直径和长度，然后扶强度条件进行校核。根据油田的实际情况，编制了抽油杆柱电算程序，并给出了设计训一算实例。