PDC Drill Bit Pre-Use Preparation & Operating Guide

We specialize in high performance steel body and matrix body PDC drill bits for oil and gas wells, water wells, and directional drilling. Custom sizes, fast delivery, and factory direct pricing.

Before running a new PDC bit into the hole, carefully inspect the previous bit.

Check gauge wear to identify any hole shrinkage or irregularity.

Look for missing or lost components such as lost cutters or broken carbide pieces. These can seriously damage the new bit. Anengjie has seen cases where downhole debris caused premature bit failure. Always clean the bottom hole pattern before running a new bit.

Stability matters. A stable PDC bit prevents deviation and maximizes rate of penetration or ROP. However, under certain hole conditions, flexibility is acceptable.

Measure outside diameter of all stabilizers and reamers before use. Oversized tools can cause stuck pipe or bit damage. Anengjie can recommend matching gauge protection designs. Contact us for support.

1. Approaching Bottom

   Increase pump flow rate to maximum circulation. Start rotary table or top drive at 30 to 60 rpm. Slowly lower the bit until it contacts bottom.

2. Forming a New Bottom Hole Pattern Break in

   Apply the recommended starting weight on bit or WOB from the Anengjie product card or bit tag for the first approximately 1 meter of new hole. Maintain starting parameters including WOB and RPM for at least the length of one full bit.

Every Anengjie PDC bit comes with a unique parameter card. If lost, contact our technical team for a free replacement PDF.

3. Gradually Increase WOB

   After the new pattern is formed, smoothly increase WOB to normal drilling level.

For very soft formations, normal WOB is close to starting WOB. For hard formations, longer break in time is needed and final WOB is higher.

Optimal WOB is reached when increasing WOB no longer improves ROP, or when torque reaches the bit limit.

4. Gradually Increase RPM

   Increase RPM to desired operating range.

For soft formations, ROP is more sensitive to RPM; higher RPM generally boosts penetration. For hard or abrasive formations, excessive RPM causes premature cutter wear. Anengjie offers abrasion resistant cutter grades for hard rock applications.

Optimal RPM is reached when ROP stops increasing with higher RPM, or when torque limit is hit. Recommended RPM range is 60 to 240 rpm. Monitor ROP versus RPM to find the lowest RPM that gives target ROP.

5. Adjusting for Formation Changes

   When drilling through changing lithology, continuously adjust WOB and RPM to balance bit life and ROP. Anengjie technical support is available for remote optimization.

Follow the same procedure as starting a new bit, without the break in phase.

1. When reaching the kelly end, reduce RPM to 30 to 60 rpm.

2. Set brake and stop feeding. Allow partial WOB to release over a few minutes.

3. Lift bit off bottom and stop rotation.

4. After connection, lower bit back in hole. Before touching bottom, open pumps to maximum flow and circulate. Start rotary or top drive at 30 to 60 rpm.

5. Once on bottom, increase WOB first, then increase RPM, same as described above.

Anengjie steel body bits provide smooth torque recovery after connections with no sudden stalls.

When using a mud motor, RPM range is limited by the motor. Harder formations require lower motor RPM. Select a high torque, low speed motor accordingly.

AR Series matrix body PDC bits extend PDC application into harder, more abrasive formations. We recommend pairing them with high torque, low speed mud motors.

In directional wells, AR Series bits build angle approximately 5 to 10 percent slower than conventional PDC bits. Adjust your expected build rate accordingly, or ask us for formation specific modeling.

1. Run pump flow rate at 50 percent of normal drilling rate while lowering to bottom.

2. Once bit begins rotating, simultaneously increase both WOB and flow rate. In extremely soft, sticky formations where bit balling is a risk, open pumps to 100 percent immediately.

3. When the directional bottom hole assembly is in rotating mode, keep pipe RPM low at 20 to 40 rpm.

Signs that indicate possible bit whirl include low ROP below 12 feet per hour or about 3.7 meters per hour at high RPM above 120 rpm, non linear change in ROP when RPM is changed, and obvious drill string vibration.

1. Reduce RPM to 30 to 50 rpm.

2. Increase WOB until ROP reaches 12 feet per hour or higher. Do not exceed Anengjie maximum recommended WOB.

3. Increase RPM in small increments and plot RPM versus ROP. When the curve becomes linear, whirl has stopped and the bit is stable.

If you still have whirl problems with an Anengjie bit, contact us immediately. Our engineers can provide remote diagnosis within 2 hours, and we may replace the bit free of charge if a manufacturing issue is found.

We are a true source factory with R&D, production, and sales of PDC drill bits integrated in one location at Suzhou Industrial Park, China.

Main products include steel body PDC bits from 3 to 26 inches with 2 to 8 blades, matrix body PDC bits for hard formations and directional wells, coring bits, hole openers, and custom bits for oil and gas, water well, and horizontal directional drilling.

Why customers choose Anengjie: factory direct pricing with no middlemen, short lead times of 7 to 15 days for standard sizes, non standard sizes and custom cutter layouts accepted, every bit is inspected and parameter tagged before shipping, and free technical support plus failure analysis service.