PDC Bit Operating Procedure

A. Preparation before drilling

(1).Inspect previous  PDC bit for body damage, lost cutters or inserts etc. Make sure no hard objects exist in bottom   hole such as teeth, tungsten carbide and steel pieces. Clean the bottom if necessary.

(2).Handle the PDC bit with care. Place the PDC bit on wooden pad or rubber mat. Do not set the bit directly on the steel floor.

(3).Check the cutting elements for damage, inside of PDC bit for any foreign matter and ensure that nozzle O-rings are in place, Install nozzles properly as the requirement.

B. Making Up The PDC Bit

(1).Clean and grease the pin or box.

(2).Fit the breaker to the PDC bit, lower the drill string onto the pin and engage the threads, and make-up to recommended torque.

C. Tripping Down The Hole

(1).Remove the breaker and carefully lower the PDC bit through the rotary table, BOP hangers.

(2).Note the presence and location of tight spots observed when pulling the previous bit out of the hole. Trip slowly through tight spots, dog legs or ledges.

(3).Wash the last three joints to bottom with full flow at 60 rpm.

(4).Approach the bottom cautiously by observing the weight and rotary-torque indicators. Tag bottom gently and pick up off bottom approximately half meter. Circulate for 5 to10 minutes with full flow.

D. Reaming

(1).Reaming long sections of underage hole with PDC bit is not recommended.

(2).If reaming is necessary, Ream slowly and avoid high torque with full flow at 60 rpm and 10 to 20 kn(weight-on-bit).

E. PDC Bit Break-in

(1).Lower PDC bit on bottom with full flow.

(2).Use 10 to 20 kn. Weight-on-bit and 60rpm to establish the bottom-hole patter with slowly drilling at least one meter.

(3).Increase the weight in 2,000-pound increments to determine optimum drilling weight-on-bit.

(4).While maintaining constant weight-on-bit, Vary the rotary speed to determine optimum drilling parameters.  

F. Drilling

(1).Reduce rotary speed in abrasive or hard sand stringers to extend PDC bit life.

(2).Adjust the rotary speed and weight-on-bit as formation changes or strings are encountered to maintain optimum drilling performance.

(3).After making connections, note the following point：

Reset pump strokes and check standpipe pressure.

‚Pump before PDC bit approach the bottom and lower PDC bit to bottom slowly at 60rpm.

ƒAdd weight slowly to normal weight-on-bit, increase rotary speed to normal.