How to Effectively Respond to Abnormal Situations During Drilling

How to Effectively Respond to Abnormal Situations During Drilling

Even with thorough preparation, unexpected abnormal situations can occur during home drilling. Staying calm and following clear steps to identify and address these situations can effectively reduce risks, ensure the safety of personnel and equipment, and minimize delays to the project.

Step 1: Immediately Pause and Accurately Assess the Situation

Upon detecting any abnormalities, such as sudden changes in machine sound, violent vibrations, a sudden drop or complete stop in drilling speed, or abnormally cloudy water discharge, the first reaction should be to immediately stop drilling, but do not hastily withdraw the drill pipe. The primary task is to work with the construction personnel to accurately determine the problem based on the observed phenomena. Common abnormal situations fall into several categories:

Underground Obstacles: The drill bit suddenly encounters hard rocks, concrete blocks, or old foundations, preventing further progress.

Downhole Accidents: Such as drill pipe detachment or drill string jamming (the drill string is stuck in the formation and cannot rotate or be lifted).

Geological Anomalies: Encountering loose quicksand layers leading to wellbore collapse, or a large influx of water or sand.

Equipment Malfunction: Abnormal machine power or damage to key components.

Step 2: Initial Responses to Different Situations

After determining the general type of problem, different initial measures can be taken:

Encountering Hard Obstacles: Do not forcefully apply pressure or ram the drill bit, as this can easily damage the drill bit or drill pipe. Slowly attempt to lift the drill string, then consult with the construction team. The usual solution is to replace the drill bit with a more powerful one (such as an alloy drill bit), or use special techniques such as "small-charge blasting" to penetrate the obstacle (requires professional personnel). If the obstacle is not large, consider slightly adjusting the drilling angle to bypass it.

Drill String Jamming or Detachment: This is a more serious situation. First, try using the equipment's own hoisting system to attempt to free the drill string with varying force and direction (such as combining forward and reverse rotation with gentle lifting). Avoid using brute force to pull the drill string, as this may cause the drill pipe to break, making the situation more complicated. If attempts are unsuccessful, do not attempt to handle it yourself; it must be handled by professional technicians using specialized tools (such as a fishing tool).

Encountering Quicksand Layers or Unstable Wellbore: Immediately stop drilling and try to keep the drill string in the hole to support the wellbore. At this point, the drilling plan needs to be adjusted.  This usually involves using "follow-up casing" or high-viscosity drilling fluid to stabilize the borehole wall and prevent further collapse. Simultaneously, the construction progress should be accelerated to quickly penetrate the unstable formation.

Large water inflow or abnormal water quality: If there is excessive water inflow, sufficient drainage measures must be prepared. If the water is dark, has an unusual odor, or contains oil, a sample should be taken and preserved, and construction should be suspended. This may indicate that a contaminated groundwater layer has been penetrated, requiring a reassessment of the site selection or rigorous water treatment.

Step 3: Communication, Decision-Making, and Documentation

Regardless of the situation, the user should maintain clear communication with the construction manager. Ask them to explain in detail the nature of the problem, possible causes, proposed solutions, additional costs and time required, and the impact on the final well quality and completion time. Before making any decisions, be sure to understand all options and risks.

It is also recommended to keep a simple record or take photos of the abnormal situation, the handling process, and the final solution as part of the project documentation for future reference.

Step 4: Prevention is Better than Cure

The best approach is prevention. Before drilling, try to understand the local underground conditions as much as possible by visiting neighbors and reviewing geological data. Choose an experienced and reputable construction team, as they have stronger capabilities in anticipating and handling anomalies. The construction contract should also clearly define the division of responsibilities and cost handling principles in case of encountering complex geological formations.

Encountering unexpected situations during drilling is a test of both the construction team's professional capabilities and the user's adaptability. Maintaining calm communication, respecting professional judgment, and seeking solutions under safe conditions are key to successfully overcoming difficulties. A successful water well often means overcoming these anticipated challenges.