干粉灭火系统管路安装中，公称直径不大于（ )的管道宜采用螺纹连接。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='29272' and id < 2383502 and id<>'2383502' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29272' and id > 2383502 and id<>'2383502' order by id asc limit 5