GRATING WELDING PROCESS FOR MANHOLE USING MAIN BARS AND TWIST BARS CUT PREVIOUSLY AND SET ON JIG FOR MANUFACTURING VARIOUS KINDS OF GRATING

摘要

PURPOSE: A grating welding process for a manhole is provided to produce various kinds of gratings by presetting a main bar and a twist bar in a jig when fabricating the gratings. CONSTITUTION: A grating welding process includes the steps of setting main bars and twist bars in a jig(20) with a predetermined interval and conveying the jig(20) by using a conveyer(30) so as to weld the main bars and twist bars. The main bars and the twist bars conveyed by the conveyer(30) are sequentially welded by means of a welding device(40). A grating(10) is fabricated by welding the main bars with the twist bars. The grating(10) is separated from the jig(20) and moved in an upward direction by means of a separation device.