顶杆

The paper gives a overall of the current situation of the development of drill pipe power tongs in well at home and abroad at first, given the manufacture techonology.

本文运用的基于自顶向下设计思想进行参数化设计的方法，现已完成了&钻杆动力钳系列产品开发&的项目。

Harpsichord 羽管键琴:A stringed instrument resembling a grand piano but usually having two keyboards and two or more strings for each note and producing tones by the plucking of strings with plectra.

一种卧式竖琴型或梯形的键盘乐器，类似三角钢琴，但通常有两层键盘（部分为一层，及其个别亦有三层）和两套或更多的弦，通过羽管或皮制拨子（拨子连接一顶重器，一般为一根直立的木杆）拨弦，赖琴键内端推动发声。

Harpsichord羽管键琴】A stringed instrument resembling agrand piano but usually having two keyboards and two or more strings for each note and producing tones by the plucking of strings with plectra.

一种卧式竖琴型或梯形的键盘乐器，类似三角学钢琴，但通常有两层键盘(部门为一层，及其个别亦有三层)和两套或更多的弦(每一套发出差别音质的音)，通过羽管或皮制拨子(拨子连接一顶重器，一般为一根直立的木杆)拨弦，赖琴键内端推动发声。

The wood of a gum tree .Having a single, undivided trunk with lateral branches, as in spruce trees.

贯顶的，塔状的主轴延伸成不分枝的茎或杆的，如云杉

At the same time, the finite staff element method is used to analyze the influence of beam rigidity; and the two new methods proposed are used to analyze the influence of connect way between piles and beam; and the conclusion is obtained that the rigidity ratio between beam and piles being 0.48 is appropriate; the continuative increase of the rigidity ratio is not significant; the worst condition is that connecting way between piles and beam is hinged; the best condition is that connecting way between piles and beam is rigid. Whether is single-row pile or are double-row piles, when the front of single-row pile or the front of the front-row pile(in the double-row piles) needed excavation, it is supposed to that ought to be carefulness to excavate, because it is that the engineering cost increased greatly.

同时，用有限杆单元法，对双排桩的连梁刚度和用文中提出的方法以桩梁连接方式进行了试验和理论分析得出如下结论：在满足不相互影响排桩间距的情况下，桩顶连梁与桩的刚度比不小于0.48是合适的，此时再增加连梁刚度无意义；桩梁连接为铰结时双排桩受力变形性质最差，刚结时受力变形性质最好；不论是单排桩还是双排桩，桩前和前排桩桩前土体需要开挖时应慎重，因为这种开挖对支护结构影响很大，造价增加很多；双排桩省钱，而且抵抗变形的能力强，值得在工程中研究和广泛应用

Auxiliary devices such as top-mounted illuminateng light,warning light,emergency stop lever,are equipped to provide safe operation and easy maintenance.

整机设有顶罩照明灯、故障报警灯、紧急停车杆等附属设备，操作安全、维修方便。*齐边系统。

Thus, when the mould is in the process of being closed, the push-back pins strike the fixed mould plate and progressively return the ejector plate assembly to the rear position.

因此，当模具闭合的时候，回程杆撞击定模板，逐渐地把顶料板组合退回到后面的位置。

When a mould is fitted to a machine which incorporates a hydraulic actuating system, providing the ejector rod is positively coupled to the hydraulic ram, the return of the ejector plate assembly follows automatically.

可是，甚至于在这种情况下，许多设计者仍喜欢装一个回程杆系统，作为一个安全部件，以确保顶料系统完全回复到早先注射阶段的位置。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。