钻进

With the increase of borehole depth, the comparative advantage of hydraulic top-drive core drill decreases. In this case, the length of drill rod stand should be increased to improve efficiency of round-trip operation.

钻孔深度加大后，动力头钻机在钻进施工效率方面的对比优势会逐渐减弱，应该考虑采取加大钻杆立根长度，从而加大起下钻速度的措施。

This allows the bit to drill around a central cylinder of rock, which is taken in through the bit and into the core barrel.

这样允许钻头围绕岩石的中心圆柱体钻进，并通过钻头进入取芯桶。

It was found out that the automation level of the drill and driver's operation level are also key factors which affect the drilling process.

本文通过对岩石的可钻性和钻进参数进行的分析研究，用已知岩性与未知岩性进行比较，能够得到相对的岩石特性，从而达到识别岩石性质的目的。

Drill for oil? You mean drill into the ground to try and find oil?

钻石油吗？你的意思是钻进地下找石油吗？

The earth is not himself into the drill ground?

是钻进大地变成不是自己的地下水？

The pin top for pre-selecting is welded on the bottom part of the bracket of core drill, the pin top is in favor of the localization of drilling hole, at the same time, it can overcome the reversal angular force acted on the core device, it enhances the rigidity of the whole mechanism.

起预定位作用的尖顶焊接于取芯钻机的机架底部，尖顶有利于钻进初始阶段时钻孔的定位，同时还能够克服作用于取芯器的反转矩，提高了整个机构的刚度。

When it is to drill a deep hole, the drill may be fixed on a ground wood beam, and then put up the drill tower.

平整场地使钻机安放平稳牢固，当深孔钻进时，可将钻机固定在自备的地木梁上，竖好钻塔。

is of importance to position finding of bit for orientational drilling.

在定向井钻进中，钻头的定位是至关重要的。

Is of importance to position finding of bit for orientational drilling.

摘要在定向井钻进中，钻头的定位是至关重要的。

It is proposed that economical performance of diamond bits be quan-titatively appraised by use of bit drilling cost .

并提出用钻头钻进成本定量地评价金刚石钻头的经济效果。

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。