起重架子的横梁通常由工字钢和（ ）等型材做成。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='24887' and id < 2124198 and id<>'2124198' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='24887' and id > 2124198 and id<>'2124198' order by id asc limit 5