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What are the essential requirements during drilling operations?

In core drilling, the requirements are to achieve "one clarity," "two diligence," "three timeliness," "four attentions," and "five no's." The specific details are:

Yi Qing: You must have a clear understanding of the conditions inside the hole.

Two Diligences: Diligently inspect drilling tools; diligently analyze the situation.

Three Timely Actions: Adjust operational methods promptly when stratigraphic changes occur; fine-tune drilling parameters in real time; and address any abnormal conditions inside the borehole without delay.

Four points to note: Pay attention to selecting the appropriate drill bit type and usage method; monitor the machine's operation carefully; ensure proper control of drilling cycles; and stay alert for changes in the geological formation.

Five don'ts: Don't arbitrarily alter the mud properties; don't blindly apply drilling parameters; don't allow rock cuttings to accumulate in the hole beyond 0.3 to 0.5 meters; don't lower excessively worn or severely bent drill tools into the hole; and don't let each shift operate independently with its own set of procedures.

How can drilling prevent hole deviation, and what aspects should be noted?

How to prevent drill holes from bending—based on insights gained in recent years, here’s a concise guide summarized into five key points, presented in the form of a catchy rhyme:

(1) Installation:

The base installation must be precise, and the drilling tower machinery must remain stable. Ensure that everything—up, down, front, and back—is aligned in a single straight line, and carefully determine the correct angle for the borehole. Safety inspections should be conducted rigorously, leaving no room for excuses when issues are identified.

(2) Opening Holes:

Onboard, ensure the remaining drill pipe doesn’t have any extra-long sections—never leave them unattended. Avoid bending the active drill rods at all costs; instead, keep them securely fastened to the rotary table assembly. Make sure the drilling tools are properly aligned, gradually increasing in diameter as you go. Maintain a moderate rotation speed, applying just enough weight to keep the process smooth and efficient.

(3) Run the casing:

The wellhead casing is lowered promptly to prevent live rock from collapsing. The casing must be properly aligned and tightly seated against the pipe wall to avoid any movement.

(4) Layer Change:

As rock layers transition from soft to hard, pressure must be relieved. When encountering a stuck drill bit, ease up gradually—slow and steady is the key. Advance the drill by 300 to 500 millimeters, then resume normal operation. Conversely, if the rock becomes harder, reduce the pressure accordingly. Don’t forget to replace the drill bit promptly, and always pair longer, larger-diameter drill tools for optimal performance.

(5) Operation:

Lithology determines how easy or difficult drilling is—operational techniques are crucial. Carefully select drilling parameters and diligently refine your approach during the process. Choose drill bits that are well-suited to the formation, and closely monitor bit wear while ensuring consistent operation across all three shifts. Pay attention to even minor differences in core sample thickness. Maintaining constant pressure and speed is essential—never compromise on this. Additionally, strictly adhere to the recommended limits for drilling mud solids, and regularly remove accumulated cuttings to prevent bit burial.

What are the key techniques for diamond drilling?

High efficiency, minimal wear—choose technical parameters carefully. If efficiency is high but wear is excessive, the technical settings need to be readjusted. Maintain a reasonable drilling speed to prevent bit burning, and keep the weight on bit moderate to minimize hole deviation. Thorough flushing is essential; always closely monitor the three gauges: the weight-on-bit gauge, the pump pressure gauge, and the system pressure gauge. Note: The "three gauges" refer to the weight-on-bit gauge, the pump pressure gauge, and the system pressure gauge.

When operating diamond drilling, what signs should you pay attention to observe?

When diamond drilling, carefully observe the following phenomena to help determine whether the operation is appropriate and whether the drilling process is proceeding normally:

(1) Machinery: Sound levels, whether the clutch is slipping, etc.

(2) Instrument: The rise and fall, or sudden changes, of the pointer.

(4) Hose:蠕动, 跳动.

(5) Water tank: Liquid level, water color.

(6) Drilling speed: Faster, slower.

(7) Drilling tools: Rotation is smooth, but requires significant effort.

(8) Operation: During diamond drilling, it's crucial to strictly adhere to the "Five No-Sweeps" and ensure the "Three Must-Lifts."

What are the "Five No-Sweeps" and "Three Must-Raises" of diamond drilling?

Five things not to sweep: Do not use a diamond drill bit to sweep holes, residual core samples, detached core samples, loose fragments, or probe stones—this is to prevent damage to the drill bit.

Three situations require pulling the drill: when downhole resistance occurs and gentle drilling pipe rotation fails to resolve it, you must pull the drill; when core blockage cannot be cleared despite attempts, pull the drill immediately; and when drilling speed suddenly drops for unclear reasons, pull the drill without delay.

What are the key points of implementing the "Three Must-Raises"?

Bring it up when it needs to be, without any hesitation.

Better to drill ten extra times than to stubbornly tolerate "lazy drilling."