BS 1868-1975(R1990) Steel check valves(flanged and butt-welding ends) for the petroleum,petrochemicaBS 1868-1975(R1990) Steel check valves(flanged and butt-welding ends) for the petroleum,petrochemical and allied industries
部份国外标准涉及版权问题,所以全部国外标准于2013年02月,全部删除!相关页面仅提供参考消息。