packer flapper valve
[新英汉石油技术词典]
packer flapper valve封隔器活瓣阀
是什么意思,packer flapper valve的解释,packer flapper valve的翻译
[石油英汉词典] packer flapper valve
packer flapper valve
[新英汉石油技术词典]
packer flapper valve是什么意思,packer flapper valve的解释,packer flapper valve的翻译
[石油英汉词典] packer flapper valve