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Q345B無縫鋼管,Q345B無縫管,Q345B鋼管-天津寶嶺鋼管貿易有限公司


Q345B無縫鋼管知識

Q345B無縫鋼管裂紋原因有哪些?

Q345B無縫管

Q345B無縫鋼管裂紋原因:

第一 組織的不均勻是管坯的原因。16Mn是以前鋼的牌號,早就改為Q345B了,這沒什么關系,注意選擇執行管坯標準的,有一定規模的廠家生產的圓鋼就行。

第二 成品退火溫度是合適的。穿孔加熱溫度1180~1230℃,偏低,這是中碳合金鋼的溫度,取1230-1250,才合適。35min是加熱時間還是爐內時間?爐內時間一般在60min以上。

第三,裂紋產生的原因,經試驗證明,管坯(圓鋼)的原因居多,內部含有較多的裂紋、夾雜、氣包等。

穿孔的溫度、工藝調整也不容忽視,若穿孔溫度低、調整不當,也會造成毛管內部組織的撕裂。


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