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磁基準(zhǔn)坐標(biāo)測(cè)量機(jī)-------外文翻譯.doc

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磁基準(zhǔn)坐標(biāo)測(cè)量機(jī)-------外文翻譯,1.緒論:在制作粒子加速器時(shí)的基本對(duì)準(zhǔn)問題是改變工件的磁中心線與外部基準(zhǔn)之間的位置關(guān)系。這一步,是建立臨界基準(zhǔn)因?yàn)樗鼘?duì)于校正誤差十分重要。這個(gè)過程有兩種測(cè)量方法:1)通過磁中心線建立機(jī)械中心線。2)通過機(jī)械中心線建立外部基準(zhǔn)。下面我們會(huì)關(guān)注論第二種測(cè)量方法,介紹兩個(gè)斯坦福線性碰撞(slc)的例子。2.目的:建立磁基準(zhǔn)是...
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此文檔由會(huì)員 wanli1988go 發(fā)布

1.緒論:
在制作粒子加速器時(shí)的基本對(duì)準(zhǔn)問題是改變工件的磁中心線與外部基準(zhǔn)之間的位置關(guān)系。這一步,是建立臨界基準(zhǔn)因?yàn)樗鼘?duì)于校正誤差十分重要。這個(gè)過程有兩種測(cè)量方法:
1) 通過磁中心線建立機(jī)械中心線。
2) 通過機(jī)械中心線建立外部基準(zhǔn)。
下面我們會(huì)關(guān)注論第二種測(cè)量方法,介紹兩個(gè)斯坦福線性碰撞(SLC)的例子。
2.目的:
建立磁基準(zhǔn)是為了聯(lián)系磁電波與外部的基準(zhǔn)面的位置。 有利于以后建立聯(lián)系,在某種意義上這種關(guān)系必須立足于全部位置公差。
斯坦福線性碰撞實(shí)驗(yàn)預(yù)計(jì)公差的工件與工件之間重復(fù)定位誤差SLC’s±100μm由以下公差組成:
磁中心線相對(duì)于機(jī)械中心線的公差 σ=±30μm
機(jī)械中心線相對(duì)于基準(zhǔn)符號(hào) σ=±50μm
基準(zhǔn)符號(hào)相對(duì)于鄰近部分 σ=±80μm
累計(jì)公差 σ =±100μm
眾所周知磁鐵的機(jī)械中心線與磁中心線的偏移量一般比測(cè)量公差小±30μm,一般假定為零測(cè)度。這個(gè)微小值必須是標(biāo)準(zhǔn)值。要特別注意利用重合誤差測(cè)量工具避免這個(gè)不明顯偏移。相反,機(jī)械中心線基準(zhǔn)測(cè)量必須適合任何磁體。這樣的±50μm測(cè)量公差只是稍微大一點(diǎn),然而卻推動(dòng)了傳統(tǒng)的測(cè)量技術(shù)達(dá)到極限。這樣就被迫去研究其它方法來測(cè)量這些數(shù)值的可靠性和精確度。
1.Introduction
One of the fundamental alignment problems encountered when building a par¬ticle accelerator is the transfer of a component’s magnetic centerline position to external fiducials. This operation, dubbed fiducialization, is critical because it can contribute significantly to the alignment error budget. The fiducialization process requires two measurements:
from magnetic centerline to mechanical centerline, and
from mechanical centerline to external fiducials.
This paper will focus on methods for observing the second measurement. Two Stanford Linear Collider (SLC) examples are presented.
2.Goals
The object of magnet fiducialization is to relate the magnet-defined beamline position to exterior reference surfaces. To be useful for later component alignment, this relationship must be established in a manner consistent with overall positioning tolerances The error budget for the SLC’s component to component alignment tolerance is as follows:
magnetic centerline to mechanical centerline δ=±30μm
mechanical centerline to fiducial marks δ=±50μm
fiducial marks to adjacent components δ=±80μm
TOTAL δ=±100μm
The offset between the mechanical and magnetic centerlines of well-known mag¬nets is generally smaller than the measurement tolerance. It is commonly assumed to be zero without measurement. When this tiny value must be mea¬sured, extreme care is necessary to avoid obscuring the offset with measurement tool registration errors. In contrast, the mechanical centerline to fiducial measure¬ment must be performed on every magnet. The tolerance for this operation is only slightly larger and pushes conventional surveying technology to its limit. Work supported by Department of Energy contract DE-AC02-76SF00515 .This has forced the search for other means of measuring these quantities reliably and accurately.