梯形

Normative references GB 150 steel pressure vessel GB 152.1 ~ 152.4 fastener hole and Shen Kong GB 196 common Cast Gate Valves thread of basic dimensions (diameter l ~ 600mm) GB 197 common thread of tolerance and fit (diameter of 1 ~ 355mm) GB 798 live bolt GB 897 stud bm = ld GB 898 stud bm = 1.25d GB 901 Class B and other long stud GB 5782 Hexagon head bolts A and B class GB 5796.1 ~ 5796.4 Cl 150, 300, 600 Lb Cast Steel Gate Valves trapezoidal thread GB 6175 2 Hexagon nut A and B class GB 9112 types of steel pipe flanges GB 9113.1 ~ 9113.26 Integral steel pipe flanges GB 12220 Universal Valve Logo GB 12221 length of the Cl 900, 1500 Lb Cast Steel Gate Valves valve structure of metal flange GB 12222 Multi-turn valve actuator attachment GB 12224 General requirements for steel valves GB l2228 General Valve carbon steel forgings GB 12229 Universal Valve carbon steel castings GB 12230 Universal Valve austenitic steel castings GB / T 12252 General requirements valve supplier ZB Jl6 006 test and test valve

引用标准 GB 150 钢制压力容器 GB 152.1～152.4 紧固件通孔及沉孔 GB 196 普通螺纹基本尺寸(直径l～600mm) GB 197 普通螺纹公差与配合(直径1～355mm) GB 798 活节螺栓 GB 897 双头螺柱bm＝ld GB 898 双头螺柱bm＝1.25d GB 901 等长双头螺柱 B级 GB 5782 六角头螺栓 A和B级 GB 5796.1～5796.4 梯形螺纹 GB 6175 2型六角螺母 A和B级 GB 9112 钢制管法兰类型 GB 9113.1～9113.26 整体钢制管法兰 GB 12220 通用阀门标志 GB 12221 法兰连接金属阀门结构长度 GB 12222 多回转阀门驱动装置的连接 GB 12224 钢制阀门一般要求 GB l2228 通用阀门碳素钢锻件技术条件 GB 12229 通用阀门碳素钢铸件技术条件 GB 12230 通用阀门奥氏体钢铸件技术条件 GB/T 12252 通用阀门供货要求 ZB Jl6 006 阀门的试验与检验

In the case of growth on the ploycrystalline diamond substrates under high methane concentration condition, diamond nano-platelets consisting of many smaller tabular crystallites with various shapes but with the same facets, such as trapezoid and parallelogram, appear in terrace and step structure on tabular surface.

在高甲烷浓度条件，多晶钻石基材上成长的奈米平板钻石，其外形结构是由各种形状(近似於梯形及平行四边形)的小平板组合而成，并且这些小平板会在平板钻石表面形成平台及台阶的结构。

The five-link front axle and trapezoidal-link rear axle are made primarily from aluminium, the steering box below directs the steering impulse directly to the wheels.

5连杆前悬架和梯形连杆后桥主要是由铝制成，指导下面方框指示直接指导冲动车轮。

Firstly, this paper discusses the development actuality of the research on double-front axle steering system and power-train of automobile. Based on the structure of the design experiences from others, the kinematics formula of double-front axle steering system is fetched, and the mathematical model of optimization design of double rocking arms mechanism and steering trapezium mechanism is established by space geometry method. Considering the difference between the real steering angle from wheels and the ideal steering angle from the ideal formula as the objective function, the optimization design method of double-front axle steering system is presented.

本文首先论述了国内外对汽车双前桥转向系统和动力传动系统研究的发展状况，在总结前人研究设计经验的基础上推导出汽车双前桥转向系统运动学关系，运用空间几何法建立了双前桥双摇臂机构及转向梯形机构优化的数学模型，以转向轮实际转角值与理想公式求出的理想转角值之间的误差达到最小为目标函数，提出了双前桥转向系统参数的优化设计方法。

For improving the maneuver stability,safety and decreasing the tire wear,the combination of the optimization software,modefrontier and msc.adams,is applied to design the steering mechanism,with bottom angle of steering trapezoid,arm length,kingpins distance and axles distance as design parameters,transmit angle as constraint,minimum error between theoretical and practical steering angle as objective function,and simulated annealing as the optimization algorithm.

为了提高汽车操纵稳定性、安全性及减少轮胎磨损，将数值优化软件modefrontier同机械动力学仿真分析软件m sc.adam s集成，以转向梯形底角、转向臂长度、主销中心距和轴距为设计参数，传动角为约束，以转向时内轮实际转角与理论转角的误差最小为目标函数，采用模拟退火算法对转向机构进行最优化设计。

In the wooden boarded system can be divided into spoon-shaped soundbox with liuqin and pipa. Round-shaped soundbox with zhongruan and daruan.

在板面系统当中，又可以分成瓢形音箱系统的柳琴、琵琶，圆形音箱系统的中阮、大阮，匣形音箱系统的筝，梯形音箱系统的扬琴。

In order to study the speed control performance of multiphase trapezoidal-wave permanent magnet synchronous motor, the mathematical model was established based on the six-phase TPMSM with Y-Y winding shifting 30° electric-degree.

为了研究多相梯形波永磁同步电动机的调速性能，基于Y-Y移30°电角度的六相TPMSM建立数学模型，在Simulink仿真环境下设计了TPMSM的电流型自控频率式调速系统。

With its fine bezel, knurled case middle, screw-down sapphire crystal back, faceted trapezoid hourmarkers, dauphine hands and multi-toned dial, this new model sublimates the identifying aesthetic features of the Patrimony Traditionnelle line.

精美表圈、滚花表壳、旋入式蓝宝石水晶玻璃表底盖、精心雕琢的梯形时标、尖剑指针、多层次银质处理表盘，这一新款腕表凝聚了Patrimony Traditionnelle系列的重要美学特色。

In the training of students making echelon screw thread by turning,the choosing and grinding of knife,putting knife into nip,putting workpiece into nip should be noticed;the lathe,choice of technics parameter,establishment of working steps should be adjusted.

在训练学生车削梯形螺纹时，要注意车刀的选择与刃磨、车刀的装夹、工件的装夹，要调整车床、选择工艺参数、确定工步。

The grease should be laid on the periphery of seal ring, the inner of ladder-shaped screw thread and chuck ring oil channel during installation.

安装时应将橡胶密封圈四周，梯形螺纹内，压环油槽内，中心管外径上涂黄油。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。