上游端 meaning in English

head end
upstream end
upstream extremity

Monitoring and control of vibration of dam during blasting demolition of upstream longitudinal concrete cofferdam at three gorges project
三峡工程纵向围堰上游端部拆除爆破震动安全监控
Insert a soft , blunt instrument into the downstream end of the valve and push the ball and seal carrier out of the upstream end of the valve
将柔软的、钝的工具插入阀门的下游端口，将球体和密封托架从阀门的上游端口推出。
The upstream end of the fire test chamber shall be filled with a 14in . length of uncoated 16 - guage steel plate positioned on the specimen mounting ledge in front of and under the leading edge of the specimen
前缘燃烧测试室上游端口中是一长14英寸厚度规格为16的无镀层钢板，该板位于样品安装壁架前端，在样品前缘下方。