共查询到19条相似文献,搜索用时 62 毫秒
1.
2.
5.
6.
田荣生 《中国新技术新产品》2013,(22):127-127
本文论述了350型修井机滚筒刹车毂水循环冷却系统的改造技术,对技术改造的主要措施与具体内容进行说明,并对改造后效果进行了评价。’ 相似文献
7.
单头等螺距梯形齿螺杆转子型线的干涉问题研究 总被引:4,自引:2,他引:2
本文针对无油螺杆式真空泵中一种常用的单头等螺距梯形级齿的螺杆转子型线,研究讨论了二转子级齿间的干涉问题。提出了保证二转子不发生干涉的二种解决方案———平移齿面法和内凹齿面法。分别推导得到齿面平移距离和内凹齿面母线方程的计算公式。其中内凹齿面螺杆转子型线在国外多种螺杆式真空泵产品中得到实际应用 相似文献
8.
9.
10.
目的为了解决某截齿齿套锻压载荷大、模具寿命低、齿套腔充填难等技术问题。方法采用数值模拟的方法,选取不同的始锻温度和冲头进给速度,对截齿齿套热锻成形过程进行模拟分析,根据模拟结果优化参数。结果研究发现上下冲头载荷的增长趋势基本一致,但在成形伞头侧壁及伞头尾部时,下冲头成形载荷的增长率相较于上冲头有所增加。采用上冲头进给速度为10 mm/s,下冲头进给速度为23.50 mm/s,始锻温度为1000℃的优化参数,其最大成形载荷不会出现明显增加,另外最大等效应力和最大损伤因子皆较小,并且金属填充效果良好。结论通过分析始锻温度和冲头进给速度对截齿齿套成形的影响,并对其进行优化和控制,得出了最优工艺参数区间,为实际生产提供了参考依据和理论指导。 相似文献
11.
12.
目的为了解决某型号曲轴轮毂中间齿形充填困难的问题。方法对齿形精压过程进行了数值模拟,分析了不同摩擦因数、减压孔尺寸对金属流动分布、等效应变及成形载荷的影响,并进行了试验验证。结果摩擦因数影响变形金属轴向和径向的流动分布,减压孔尺寸影响分流面位置及金属的流动速度;根据模拟结果,生产出了合格的产品。结论摩擦因数过小,径向流动阻力减小,不利于金属轴向流动充填齿形,较大的摩擦因数有利于齿形充填,但是摩擦因数过大会导致成形载荷过大;随着减压孔直径增大,金属的分流面外移,对大直径处齿形充填不利。模拟结果对实际生产具有重要的指导意义。 相似文献
13.
以三辊斜轧空心减径过程中辊形对轧制过程的影响规律为研究对象,对无缝钢管三辊斜轧空心减径过程进行分析研究,建立了辊型的数学模型.利用有限元软件分析辊形曲线对成形过程的影响,并在某三辊实验轧机上进行实验分析,将实验结果与有限元模拟结果进行对比和分析.结果表明,当减径量小于10 mm时,入口锥角为2.5°的辊型对应的轧件在接近均整变形区金属流动十分平缓和均匀,轧件前端面也从三角形截面逐步变为圆截面;当减径量在14 mm左右,采用入口锥角为3.5°的辊型时轧件的质量较好. 相似文献
14.
A generalized mathematical model is developed to predict the changes of temperature, rolling pressure, strain,strain rate, and austenite grain size for plate hot rolling and cooling processes. The model is established mainly by incorporating analytical an 相似文献
15.
Mina Rezaye Abbasi Charkhi Majid Aminnayeri Amirhossein Amiri 《Quality and Reliability Engineering International》2016,32(5):1655-1661
A profile is a relationship between a response variable and one or more independent variables that can describe the quality of a process or product. On the other side, for an in‐control process, capability indices are the criteria for process quality improvement that allows meeting customer expectations. Recently, evaluating the process capability of profiles has been investigated by some researchers. In all of these efforts, the response variable in the profile follows a normal distribution. However, sometimes, this assumption is violated, and the response variable may follow a binary or binomial distribution. In this paper, we propose two methods to measure the process capability when the quality of a process is characterized by a logistic regression profile. The performance of the proposed indices is evaluated through simulation studies. Finally, the application of the proposed methods is illustrated through a real case. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
16.
相比于传统切削加工,复杂型面滚轧成形轴类零件的强度提升、表面质量好、加工时间短、材料利用率高。复杂型面滚轧工艺类型更多、成形过程运动更复杂,不同复杂型面滚轧工艺所要求成形设备结构及运动方式也各不相同,因此首先分析了复杂型面滚轧工艺类型及衍生分支,进而阐明了相应的平板模具搓制、轮式模具滚轧、轴向进给主动旋转滚轧的设备结构原理及运动特征,评述了不同类型的复杂型面滚轧设备的最新研究进展,介绍了具有代表性的典型产品。在此基础上指出了伺服化是复杂型面滚轧设备发展趋势,复合振动或温成形是解决高强材料复杂型面精确滚轧问题的途径。 相似文献
17.
18.
Ramezan Nemati Keshteli Reza Baradaran Kazemzadeh Amirhossein Amiri Rassoul Noorossana 《Quality and Reliability Engineering International》2014,30(5):633-644
Profile is a relation between one response variable and one or more explanatory variables that represent quality of a product or performance of a process. On the other hand, process capability indices are measures to help practitioners in improving the processes to satisfy the customer's expectations. Few researches are done to account for the process capability index in the areas of profile monitoring. All of these researches are focused on process capability index in simple linear profile. In all of these methods, response variables in different levels of explanatory variable are considered, and the relationship in all range of explanatory variable is neglected. In this paper, a functional method is proposed to measure process capability index of circular profiles in all range of explanatory variable. The proposed method follows the traditional definition of process capability indices. The functional method uses reference profile, functional specification limits and functional natural tolerance limits to present a functional form of process capability indices. This functional form results in measuring the process capability in each level of explanatory variable in circular profile as well as a unique value of process capability index for circular profile. The application of the proposed method is illustrated through a real case in automotive industry. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
19.
评述了重载汽车国产化离合器片的成分、性能、工艺和研制过程,并将其摩擦磨损性能和进口件进行了比较,结果表明,国产件与国外同类产品的摩擦磨损性能相当。 相似文献