A leading manufacturer in China for suppling drilling tools for mineral exploration and geotechnical drilling indutries, also the Strategic Partner of Atlas Copco/ Epiroc since the year of 2012 (XZ is the famouse brand in the industry in China)
August 20, 2020
Drilling Parameters and Tips for Diamond Core Drilling
-- China Geological Equipment Group Wuxi Drilling Tools Co., Ltd
For Maximizing the performance of the bits and Minimizing the risk of accident in the hole, Do Not Mixing different maufacturer's bits with ours.
Successful exploration drilling results from a clear understanding and cooperation between two professionals, the Diamond Driller and the Geologist. Drilling operations are controlled by geologists but they lack the knowledge and experience to optimize the operation of the drill. The Professional Diamond Driller should not hesitate to share his knowledge to improve the operation. A professional diamond driller will adjust all these parameters matching the drilling condition.
Drilling Operation Parameters
Rotation speed should be adjusted considering:
a. Diameter of bit
c. Depth of drilling
d. Deviation issue
e. Vibration of string rod
RPM too high with low ROP can cause polishing of the bit
RPM too low may result in faster wear of the bit
The weight on bit depends on rock and bit type, RPM, ROP and water flow.
Try to maintain a constant ROP by increasing or reducing the WOB. Always adjust the
hold back pressure while adding rods.
a. Best cost per meter
b. Smooth operation
c. Best bit life
d. Sharp bit
|Too Low||Too High|
|Premature wear of bit||Low productivity|
|Rod and barrel damage||Risk of polishing the bit|
|Hole deviation||Low bit life|
|Premature wear of rig|
WATER FLOW （LPM）
Drilling performance is directly related to the fluid flow over the bit, fluid flow has very important different functions :
b.Cooling the bit
c. Lubricating the bit and rods
The rate of penetration is the key parameter during drilling.
It results from the right combination of WOB and RPM for a rock type and condition.
Well -maintained ROP ensures :
a.best cost per meter
c. best bit life
Revolution Per Centimeter is an indicator coming from
the division RPM / ROP
Example of an N size bit turning @1200 rpm
and run @15 cm/min
RPC = 1200 / 15 = 80
Maintain the RPC within 50 < RPC < 100
a.Add WOB until torque rises, once ROP increases, reduce WOB to maintain desired ROP
b.Reduce RPM by half, wait until torque and ROP rise. Return speed to normal operation.
c. Reduce the water flow
The information contained as per above provides
the reader with suggestions and guidelines dealing
with a number of hypothetical situations. CGE Group
Wuxi Drilling Tools Company accepts no responsibility
for damages, consequentialor otherwise, resulting from
application of such guidelines and suggestions. The
reader is strongly encouraged to contact an authorized
CGE Group representative to obtain guidance in dealing with
specific real situations.