芯棒

Analyzing and simulating of the deformation law of the ceramic downspout product after overcoming the shortage of powder material models in the software of MSC. MARC. It shows out the important effects of various factors and the shape of mandril during the process. And it is obvious that the shape of the top mandril has more effects on the process than the bottom.(3) Showing out the important effects of model figure on the flowing of powder and the forming of low-density fields from the analysis. After changing the top of the mandril into spherical shape, an improving model is putting out so that the distribution of stress and strain turns to be even and proper and that the flow rule of powder grains is better.(4) Calculating of the dimensional precision and the cutting ratio of the product and analyzing of the effects of such factors as rubber aging, loading process, mandril, friction etc. on the cutting ratio.

MARC存在的粉末材料模型方面的设计缺陷后，对连铸水口粉末成形件的变形规律及影响因素作用进行了模拟分析，指出芯棒形状对成形件的变形有较大影响，并且芯棒顶部形状与芯棒底部形状相比，对粉末变形有更大影响；(3)分析了成形件出现低密度区域的原因，指出模具形状对粉末流动以及粉末成形件低密度区域的形成有重要作用，提出了密度分布优化改进模型：改进模具顶部形状，并将芯棒顶部设计成球面后，粉末成形件顶部区域的应力、应变分布更加均匀、合理，粉体颗粒流动情况明显改善，低密度区域明显缩小；(4)计算了成形件的尺寸精度及切削率，并指出除模具形状的影响外，充填密度、橡胶模具老化、加载工艺等其他因素对总体切削率也有相当的影响。

In order to accurately determine the forming temperature and time of the sintered wick and to offer methods for the fixation and extraction of the mandrel as well as the infilling of copper powders, this paper analyzes the forming mechanism of copper powders in the wick and investigates the manufactu-ring process of the capillary structure of the sintered wick in the micro heat pipe.

文中分析了铜粉颗粒在吸液芯中的成型机理，探讨了烧结式微热管吸液芯毛细结构的制造工艺，解决了吸液芯成型温度与成型时间的确定，以及烧结时芯棒的固定、抽出与铜粉颗粒的填充等相关问题。

This paper analyzes the forming mechanism of copper powders in wicks, probes into the manufacturing process of capillary structures of sintered wick in micro heat pipe, and offers means for ascertaining forming temperature and forming time, fixating and extracting the mandrel as well as infilling copper powders.

本文分析了铜粉颗粒在吸液芯中的成型机理，探讨了烧结式微热管吸液芯毛细结构的制造工艺，主要解决了吸液芯成型温度与成型时间的确定，以及烧结时芯棒的固定、抽出与铜粉颗粒的填充等相关问题。

Briefed in the paper is the current domestic situation concerning demand of medium-sized mandrel s.

简要说明了国内中直径芯棒的需求情况，分析了皮尔格轧机生产中直径芯棒的可行性。

The results show that increasing the ball numbers and mandrel extension length may reduce the ovalization, but leads to more remarkable wall thinning; the ovalization becomes more severe with the larger bending angle; the smaller the relative bending radius, the larger the ovalization is; the ovalization and wall thinning degrees are both smaller in the case of pressure die with dry lubricant; and under the same bending condition, the ovalization of LF2M tube is larger than the one of 1Cr18Ni9Ti tube.

结果表明，增加芯头个数与芯棒伸长量都能减小弯管的截面畸变，但两者都导致弯管壁厚减薄量增大；随着弯曲角度的增加，截面畸变越严重，相对弯曲半径越小，无芯棒与芯头支撑段弯管的截面畸变愈严重；在压块无润滑情况下，弯管的截面畸变和壁厚减薄量都小，并且在同等弯曲条件下，1Cr18Ni9Ti弯管的截面畸变小于LF2M弯管。

Then after analysising each characteristics of phosphate glass material, the fiber rod-in-tube by invaginating core rod, inside cladding and outside cladding is used to fabricate the Er/Yb phosphate glass fiber successfully by polishing and vacuumizing fiber rod-in-tube.

利用玻璃浇注方法得到增益玻璃芯棒，然后对芯棒进行抛光处理，并且采用芯棒、内包层玻璃管和外包层玻璃管套接的方法制作光纤预制棒，将制作的预制棒进行了粘度等测试，并抽真空加热到一定温度条件下成功地拉制出芯径5μm，外包层65μm的单模铒镱共掺磷酸盐增益介质玻璃光纤。

In industrial production and in experiments, the qualified rifled tubes are produced by the drawing with reversed tapered and uniform-pitch plug. The key design features are given when using this kind of plug.

在实际生产中和实验中应用倒锥形等螺距芯棒拉拔出了理想的内螺纹管，并提出了采用这种芯棒时芯棒几何参数的设计原则。

The results show that nonlinear dry friction between mandril and tube conduces to the self excited vibration of tube and the drawing speed is the main factor which determines whether the mandril static balance is stable.

分析结果表明，抖纹产生的主要原因是芯棒与钢管之间的非线性干摩擦力导致芯棒产生自激振动；钢管的拉拔速度及钢管表面润滑层的好坏是决定芯棒的静平衡位置是否稳定的关键因素，提高拉拔速度可将干摩擦阻尼转化为粘性阻尼，同时也使拉拔速度远离临界速度，从根本上消除抖

Then install a mounting bar and two mandrils in one side of the turret. Remember that the screw shall not be tightened.

8检查转塔内模芯推板活动是否灵活，然后在转塔的一边装上芯棒安装条和二根芯棒，注意螺钉不要拧紧。

A multiclad layer optical fiber prefabricated rod includes core rod and outer clad layer; the core rod consists of core layer, inner clad layer and low-hydroxyl high-purity clad layer in sequence, and the outer clad layer includes a high-purity outer clad layer and a subhigh-purity outer clad layer.

本发明涉及光纤制造领域中一种多包层光纤预制棒及制造方法，它包括芯棒和外包层，芯棒由芯层、内包层、低羟基高纯包层依次组成，外包层分为高纯度外包层和次高纯度外包层，它解决了现有的光纤制造技术中，光纤预制棒的外包层所使用的高纯原材料比重过大，从而导致高纯原材料利用率低、制造成本高的问题。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。