The use of diamond cord core drill bits must be done step by step according to the requirements of the onion, not to be rushed, and the drill tool assembly, deployment, and maintenance must be done well.
The use of diamond rope core drill bit must be carried out step by step according to the requirements, not too hasty, and the assembly, deployment and maintenance of drilling tools must be done well<br>
The use of diamond coring bit must be done step by step according to the requirements of onion, not in haste, and the assembly, allocation and maintenance of drilling tools must be done well.