Chinese Industry Standard: DZ/T 0056-1993

Drilling of tri-gyroscope drill bits in hydrological wells

水文水井钻探三牙轮钻头

中华人民共和国地质矿产部

This standard is the original Chinese electronic standard.
After you successfully purchase, we will send the electronic version of this standard to your email address.
If you need translation, please contact email: ChineseStandardsLibraryS001@gmail.com.