Jin Weiguo

Follow

Person

Tienjing, CN

People

Patents Grantslast 30 patents

Information Patent Grant
Device for clamping drill pipe and the like in mouse hole pipe
- Patent number 4,756,538
- Issue date Jul 12, 1988
- The Science and Technic Department of Dagang Petroleum Administration
- Chen Yuehui
- E21 - EARTH DRILLING MINING