Design and Process Control of Cable Length with Millimeter Accuracy of FAST Project

doi:10.3901/JME.2017.17.017

Abstract

Abstract: The length accuracy requirement of the cables of reflector of five-hundred-meter aperture spherical radio telescope (FAST) is extremely high, which reaches up to ±1 mm and 1/10000 of cable length. The method of over tensioning and adjusting the cable length under constant temperature is put forward. The special cable structure for length adjustment, stabilization measure for cable length, measuring and control system and the technology and process for adjusting cable length are introduced in detail; and the measurement errors caused by various factors are calculated and corrected. Through the process test, design lengths, measured lengths and length errors of 48 cables selected from 16 kinds of specifications used in the FAST project were statistical analyzed and the results show that all the length errors of cable are less than ±1 mm and are conformed to the normal distribution, which meet the acceptance criteria of the cable network of FAST project.

Key words: cable net, five-hundred-meter aperture spherical radio telescope, length measurement

CLC Number:

TU399

ZHU Wanxu, DENG Lijiao, HUANG Ying, OU Jinping. Design and Process Control of Cable Length with Millimeter Accuracy of FAST Project[J]. Journal of Mechanical Engineering, 2017, 53(17): 17-22.

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