Method of error compensation for precise grinding the helical rotor tooth profile

针对成形法精密磨削加工螺杆转子螺旋面的问题,研究了螺杆转子加工过程中由工艺系统误差产生的齿廓加工误差的补偿方法。提出了一种基于首件转子磨削后的齿; 廓测量误差,进行预处理再修整砂轮的新算法。使用处理后的补偿数据对砂轮修整后,加工误差明显减小与收敛,大大提高了磨削转子的齿廓制造精度。Aiming at the process of the machining screw rotor helical surface by; forming precision grinding, the compensation method of tooth profile; error caused by the process system error in the process of screw rotor; machining is researched. A new pretreatment and refinish grinding wheel; algorithm is proposed which based on the measurement error of the tooth; profile after the first rotor grinding. After the grinding wheel was; dressed base on the compensated data, machining error is obviously; reduced and convergence, the machining precision of root is improved; obviously.陕西省地方重大资助项

Research on Measurement and Error Evaluation of Screw Compressor Rotors

螺杆转子作为螺杆压缩机的核心部件，其工作齿面是由螺杆转子齿廓端面型线绕螺杆转子回转轴作螺旋运动形成的螺旋面，是典型的螺旋面工件。随着先进制造技术、计算机技术的发展，螺杆转子齿廓形状、齿距、与螺旋线等关键几何量的高精度、快速检测技术获得了快速发展，国际上先进的检测设备及专业检测软件已经相当成熟，国内螺杆转子精度检测技术处在刚刚起步阶段，检测软件及技术与国外存在着较大差距，检测设备主要依靠国外进口。 在此技术背景下，为了实现螺杆压缩机转子齿面廓形关键精度指标的高精度快速检测，论文围绕着螺杆压缩机转子专用测量仪及精度检测关键技术这一研究课题，主要在以下几个方面做了较为深入的研究工作： 1.根据螺...As the critical component of the screw compressor, Screw rotor working surface is a typical spiral surface which is formed by the spiral movement of the screw rotor profile. With the development of the advanced manufacturing technology and computer technology, High precision and rapid measuring technology of screw rotor profile shape, pitch ,and spiral line have been developed rapidly. Internation...学位：工程硕士院系专业：航空航天学院_工程硕士(机械工程)学号：1992013115292

Research on Grinding Forming Cutter Location of Ball-nose End Mill with “S”Shape Major Cutting Edges

基于球头立铣刀“S“形刀刃曲线完成了球头前刀面和后刀面的砂轮刀位轨迹计算,根据CnC工具磨床转换为机床的运动参数,结合计算机语言及切削仿真验证了数学模型的正确性,为“S“形刃球头立铣刀的磨削成形提供了理论依据。Based on the ball-nose end mill with "S"shape major cutting edges,we completed the cutter location( CL) datas calculation on the rake face and relief face.According to the CNC grinding machine,the CL datas are converted into the motion parameters of the machine,and then combining with the computer language and cutting simulation,the mathematical model has been proved to be correct.This study provides theory basis for the grinding forming cutter location of the ball-nose end mill with "S"shape major cutting edges.福建省产学研重大项目(2014H6025

The preparation of lanthanum,cerium doped TiO_2 ultrafiltration membrane

考察了镧、铈掺杂对二氧化钛(TIO2)超滤膜的影响。镧掺杂可以有效抑制TIO2晶型随烧结温度增加的急剧转变。镧、铈掺杂可以有效控制膜层的粒径和孔径,并提高其抗酸碱性能。TIO2膜层粒径为60~80nM,孔径为10~60nM,抗酸碱性能较差;而经镧、铈掺杂后的TIO2膜层粒径为50nM左右,孔径为10~20nM,抗酸碱性能较好,其中镧掺杂效果优于铈掺杂。The influences of lanthanum and cerium doping on the performance of TiO2ultrafiltration membrane were investigated.The significant TiO2crystal structure change with the increase of calcination temperature could be effectively suppressed by lanthanum doping.Lanthanum and cerium doping could not only effectively control the particle and pore sizes in membrane layer,but also improved the acid and alkali resistance.TiO2membrane layers were obtained with particle sizes of 60-80nm and bore diameters of 10-60nm.Lanthanum and cerium doping TiO2 membrane layers were obtained with particle sizes around 50nm and bore diameters of 10-20nm.In addition,the performance of lanthanum doping was better than cerium doping

Al_2O_3含量对PVDF/PVC/Al_2O_3共混中空纤维膜的影响

以聚偏氯乙烯(PVDF)、聚氯乙烯(PVC)和纳米氧化铝(Al2O3)三元共混,制备中空纤维膜,探讨Al2O3含量对膜性能的影响。结果表明,由于适量Al2O3的加入,中空纤维膜膜孔结构明显改善,大孔减少,微孔增多;亲水性明显提高。Al2O3为最佳含量3%时,水通量和截留率分别达到了289L/(h·m2)和77.2%

纺丝参数对PVC/PVVM中空纤维膜结构及性能的影响

采用浸没沉淀相转化法,并通过对纺丝参数的控制,制备不同性能的聚氯乙烯(PVC)/氯醋树脂(PVVM)共混中空纤维膜,为超滤膜的制备提供了可靠的理论和实践依据。其中,铸膜液挤出压力、芯液流速和卷绕速度影响着膜的内径和壁厚,入水距离则显著改变膜的纯水通量和截留率。此外,添加纳米Al2O3可改善膜的结构及性能

The preparation and performance of alumina ultrafiltration membrane

由溶胶-凝胶法与水热法相结合,成功制备了氧化铝超滤膜。利用SEM、Xrd等表征手段,研究膜层晶型、粒子形貌、孔径大小及其分布、膜层厚度等的合理调控,并表征其通量、截留率和耐酸碱性能。结果表明,水热处理溶胶并于合适温度下烧结,可有效调控超滤膜膜层的晶型和粒子的形貌;通过分散剂PEg合适型号的选择,可有效调控膜孔孔径及其分布;合适的涂膜液浓度并适量的成膜助剂PVA,可有效调控膜层厚度并避免其开裂;当氧化铝呈α态时,超滤膜具有优秀的耐酸碱性能。Alumina ultrafiltration membrane was prepared by sol-gel hydrothermal method.SEM and XRD were employed to characterize the crystal form,particle morphology,pore size distribution and thickness of membrane layer surface so as to achieve a good control of the membrane layer characteristic.In addition,the flux, rejection,acid and alkaline resistances of the membrane were also tested.The results showed that crystal form and particles surface morphology of ultrafiltration membrane could be efficiently controlled by treatment with hydrothermal method followed by sintering at suitable temperature.Pore size and pore size distribution could be well tuned by using different types PEG as dispersant agents.The thickness and cracking of membrane layer could be efficiently controlled by changing the concentration of the coating solution and by adding suitable amount of PVA.It was found thatα-Al2 O3 ultrafiltration membrane displayed a better acid and alkaline resistance than that of transition-state