螺杆泵容积效率特性分析与螺杆齿面精确成型方法研究

发布时间：2018-01-18 13:23

本文关键词：螺杆泵容积效率特性分析与螺杆齿面精确成型方法研究　出处：《重庆大学》2014年博士论文　论文类型：学位论文

【摘要】：课题来源于国家自然科学基金面上项目“高效三螺杆泵转子型线设计新方法及关键技术研究”（项目编号：50875268）和“多级变速螺杆泵基础理论与关键技术研究”（项目编号：51175522）。螺杆泵因具有优越的工程适应性和经济实用性在海洋钻井平台、舰船、精密机床、石油化工等领域应用日趋广泛。《中共中央关于制定国民经济和社会发展第十二个五年规划的建议》明确指出，高端装备制造业处于七大战略性新兴产业的核心地位，将在重点领域集中力量加快推进。螺及杆泵作为重点发展的高端装备部件，将为我国高端装备制造业的发展增加动力，成为战略性新兴产业发展的重要支撑。同时，“十二五”期间我国将投入3000亿重点发展海洋工程装备，包括海洋钻井平台、各种海洋工程船舶及潜艇等。因此，螺杆泵作为重要的高端装备基础部件，需求量巨大，具有广阔的发展前景。然而，螺杆泵属于高精度机械产品，其对设计和制造的精度很敏感。由于我国生产企业对螺杆泵工作机理认识不清晰，设计及加工方面的技术不够完善，使得生产出的产品存在容积效率低、流量特性不稳定、齿面磨损严重、功耗大等技术瓶颈，长期以来高端螺杆泵产品基本上依赖进口。为此，为提高我国高端装备制造业的国际化水平，减小我国在螺杆泵等高端装备部件对国外的依赖，开展螺杆泵系统创新设计理论与方法研究，突破螺杆泵设计制造关键技术难题，对提高我国机械装备配套自主创新能力具有十分重要的社会经济意义和工程实用价值。本文以螺杆泵关键核心部件螺杆副为研究对象，利用流体动力学、泄漏理论、接触理论、空间包络理论等，深入分析泵腔内流场运动学、动力学特性，研究探讨螺杆构型原理及其结构与螺杆泵容积效率特性参数匹配的设计理论和方法，建立考虑啮合间隙的螺杆齿形设计模型，形成螺杆齿面成型刀具精确齿形设计方法。论文主要工作如下： ①在定义容积式机械吸入能力的基础上，建立螺杆泵吸入能力计算数学模型，详细分析螺杆泵转速、螺杆螺旋升角、输送介质等对螺杆泵吸入能力的影响；研究螺杆泵吸入能力对容积效率特性的影响，得到螺杆泵关键设计参数与螺杆泵吸入能力的匹配关系，提出提高螺杆泵吸入能力的设计方法。 ②基于流体力学边界层分离理论，在深入分析螺杆泵吸入能力的基础上，结合圆柱绕流现象，对圆柱绕流迹线及其分离点进行计算，建立圆柱绕流边界层分离优化模型，运用图形和解析的方法求解优化方程，结合螺杆转子端面几何特性，获得优化流线型体三维模型，通过理论分析的方法验证优化模型的合理性。 ③内泄漏是泵泄漏的主要因素。针对螺杆泵桶壁间隙、啮合间隙等决定螺杆泵性能的关键间隙的设计问题，在研究螺杆各项间隙构成原理的基础上，运用流体力学间隙泄漏理论和小孔泄漏理论，分别建立泵腔间隙泄漏压差流和剪切流模型，分析螺杆泵桶壁间隙和啮合间隙的泄漏量，得到螺杆泵不同间隙泄漏的数学模型；以主动螺杆2头、从动螺杆3头的双螺杆泵为例，理论计算与试验对比分析螺杆转速、压差对泵泄漏的作用机理，揭示螺杆转速、泵进出口压差对螺杆泵流量特性及容积效率特性的影响规律。 ④针对螺杆泵关键部件螺杆转子设计过程复杂、加工难度高导致啮合间隙不均匀的问题，在分析螺杆啮合间隙形成机理基础上，运用空间解析几何基础理论，提出基于啮合间隙的螺杆齿形优化设计新方法，建立螺杆加工过程进刀轨迹-螺杆齿形-啮合间隙转换方程，，深入分析轴向、径向、法向等不同进刀方式对螺杆啮合间隙、螺杆齿形偏差的影响规律；结合微分几何等距曲面构型原理，得到预定加工间隙的螺杆端面齿形。 ⑤针对由离散点组成的任意端截面螺杆齿形，基于齿轮啮合原理，运用三次样条插值方法求得螺杆成型刀具齿形；研究螺杆与刀具在加工过程中的空间包络特性与几何特性，结合机床、螺杆、刀具的协同运动所生成的接触线的形状和空间位置参数，创新性地提出一种基于离散点齿形的螺杆加工成型刀具设计方法--形位几何法，与齿轮啮合原理的方法进行对比表明：形位几何法简化刀具-工件包络求解模型，克服传统啮合理论设计刀具时无法精确计算齿形曲线尖点的关键技术难点，提高螺杆成型刀具齿形设计精度，并通过试验验证形位几何法的可行性及精确性。
[Abstract]:The subject is derived from the project " High - efficiency three screw pump rotor profile design new method and key technology research " ( Project No . : 50875268 ) and " Multi - stage variable speed screw pump basic theory and key technology research " ( Project No . : 51175522 ) . Because of its excellent engineering adaptability and economic practicability , the screw pump is widely used in the fields of offshore drilling platform , ship , precision machine tool and petrochemical industry . Taking the screw pair of the key core parts of the screw pump as the research object , using the fluid dynamics , the leakage theory , the contact theory , the space envelope theory , etc . , the kinematics and dynamic characteristics of the flow field in the pump cavity are analyzed in detail , the design theory and the method for matching the screw configuration principle and the parameter matching of the volume efficiency characteristic parameters of the screw pump are deeply analyzed , the screw tooth profile design model considering the meshing clearance is established , and the precise tooth profile design method of the screw tooth surface forming tool is formed . On the basis of defining the mechanical suction capacity of the screw pump , the mathematical model of the suction capacity of the screw pump is established , the influence of the screw pump speed , the screw lifting angle , the conveying medium and the like on the suction capacity of the screw pump is analyzed in detail , and the influence of the suction capacity of the screw pump on the volume efficiency characteristics is studied , and the matching relation between the key design parameters of the screw pump and the suction capacity of the screw pump is obtained , and the design method for improving the suction capacity of the screw pump is proposed . ( 2 ) Based on the theory of fluid mechanics boundary layer separation , based on the in - depth analysis of the suction capacity of the screw pump , combining the cylinder winding phenomenon , the cylinder winding trace and its separation point are calculated , the optimization equation is solved by means of the graph and the analysis method , the three - dimensional model of the optimized streamline body is obtained by combining the geometric characteristics of the end face of the screw rotor , and the rationality of the optimization model is verified by the method of theoretical analysis . In this paper , the main factors of pump leakage are the internal leakage . Based on the principle of screw pump barrel wall clearance , meshing clearance and so on , a mathematical model of pump cavity clearance leakage differential pressure flow and shear flow model is established by using the theory of fluid mechanics gap leakage theory and small hole leakage theory . On the basis of analyzing the formation mechanism of screw meshing gap , a new method of screw tooth profile optimization design based on meshing gap is put forward . On the basis of gear meshing principle , the shape and space position parameters of the contact line generated by the cooperative motion of the machine tool , screw and cutter are studied . The key technology difficulties of the tooth profile curve point can not be accurately calculated when the cutter is designed by the geometric method . The feasibility and accuracy of the geometric method of the shape position are verified by the test .

【学位授予单位】：重庆大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TH327

【参考文献】