PDC Drill Bit Application Instructions

Bit selection

1. Please reading litholoay descrition and bit records of adiacent wells carefully, and analyzing formation characteristics

2. Selecting appropriate PDC type in accordance with lithology.

Preparation before drilling

1.Inspect previous bit for body damage, lost cutters or inserts etc. Make sure there are no any junk on bottom hole, and clean

the bottom hole if necessary.

2. Bit must be handled with care in order not to damage cutters and hard substances

3. Check if there is any damage on bit cutters and if there is any foreign matter inside the bit.

4.Check if installing nozzle is meet requirements, and replace nozzles if necessary.

Marking up the bit

1. Clean bit threads and apply grease on threads.

2. Fit the breaker to the bit, lower the drill string onto the pin and engage the threads.

3. Locate the bit and breaker in the rotary bushina, and make-up the bit to the recommended torque

Tripping in

1. Remove the breaker and carefully lower the bit through the wellhead device in order not to damage it

2. Shrinkage, shoulder, dogleg and key seat of borehole should be cautious when bit through blank hole

3. Start pump and cycle drilling fluid to wash bottom hole when dril to a point about 30 meters to bottom of the hole.and rotate drill string at the low speed not more than 60rpm.

4. Approach the bottom cautiously by observing the weight and rotary torque indicators. Tag bottom hole gently andpick up off bottom approximately half meter. Circulate for 5 to 10 minutes with full flow.

Reaming

1. Reaming long sections of undergauge hole is not recommended.

2. lf reaming operation is necessary, it is strongly recommended that the reaming operation should be done withmaximum flow rate circulation, specific weight on bit not exceed 90N/mm (diameter), rotary speed not exceed 60 rpmwhere stuck was encountered when tripping in.

Bit break-in

1.Overusing disnlav instruments when bit annroach bottomhole. if the WOB and toroue increase. that shows bit have arived athotomhole. Use not more than 90N/mm. weicht-on-bit and 40 to 60rom to establish the bottomhol patern at east half meter

2. Bit break-in is finished and should be adijusted RPM to obtain optimal drilling parameter combination.

3. Drilling parameters adjustment should be selected within the limits of the recommended parameters refer to recommendeddrilling parameters optimization method.