公称直径

对中压燃气管道，若公称直径不大于200mm，采用PE管；

For middle-pressure gas pipeline , the PE pipe is used if the nominal diameter does not exceed 200 mm ;

在钢厂的循环发电工程中，各钢厂利用公称直径d≥200mm的大型调节阀对混合煤气进行压力控制。

Steel mills using waste gas in combined cycle power project , steel mills use the nominal diameter ≥ 200mm of large control valve to control pressure of the mixed gas .

GB/T17587.2-1998滚珠丝杠副第2部分：公称直径和公称导程公制系列

Ball screws Part 2 : Nominal diameters and nominal leads Metric series

具有价格低及公称直径不受到限制的特点。

The utility model has the advantages of low price and non-limitation of nominal diameter .

晶粒的弗里特直径、平均截距、公称直径之间关系的研究

Investigation of the Relations among Frit Diameter , Average Intercept and Nominal Diameter of Crystall Grain

GB/T9019-1988压力容器公称直径

Nominal diameter of pressure vessel

水表水头损失的计算和水表公称直径的选择

The Calculation of the Head of Water Meter and the Choice of Nominal Diameter of Water Meter

弯曲半径等于或小于公称直径的180°冲压焊接弯头的制造技术

Manufacturing Tecnology of 180 ? Stamping and Welding Elbow with Crooked Radius Equal or Smaller than Nominal Diameter

端子数出线口方向及数量，公称直径可任意变化。

The terminals number , outlet directions , outlet ` s number and nominal diameter can be changed at will .

旁路阀公称直径与管道公称直径相同，耐压等级也与工艺耐压等级一致。

Bypass Valve with nominal diameter of the same nominal diameter pipeline , pressure level pressure level is also consistent with the process .

其优化目标函数的决策变量为管网各管段离散的标准公称直径，并考虑了和实际工程相对应的水力约束条件。

Diameter of the pipe discrete is objective function in which the decision variables And the hydraulic constraints is considered and corresponded the actual of the actual project .

指出螺栓联接的扭紧力矩值不仅与螺栓的公称直径及性能等级有关，还与能否保证联接可靠工作有关。

The value of tightening torque is relative not only to the nominal diameter and quality class of the bolt , but also to the security of the threaded fastener .

本文叙述了弯曲半径等于或小于公称直径的180°冲压焊接弯头的制造技术以及弯头的展开图作法、弯头胎模具、弯头冲压和弯头成形组焊技术等。

This paper describes the manufacturing tecnology of 180 ° stamping and welding el-how with crooked radius equal or smaller than nominal diameter . It also introduces the developed diagram of elbow and so on .

建立了以壳体质量最轻为设计目标、以内径（公称直径）和名义壁厚为设计变量的优化设计的数学模型。

The mathematical model of optimum design for the pressure vessel is derived . This model takes the minimum mass of shell as objective function , and takes internal diameter & nominal diameter and nominal thickness as the design variables .

GB/T7996-1987搪玻璃容器公称容积与公称直径

Nominal volume and nominal diameter for glass-lined vessel