HGJ 45—91法兰RF 50—0. 6管法兰的密封面类型是（ ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='24818' and id < 2121708 and id<>'2121708' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='24818' and id > 2121708 and id<>'2121708' order by id asc limit 5