A Costly Depth Discrepancy in Wireline Logging
A simple oversight can derail an entire wireline well logging job. I once worked on a project where a depth discrepancy caused major confusion. The logs were misaligned, and after a thorough investigation, the root cause was identified: the GEO-LOG measuring wheel had the incorrect rim size for the logging cable being used.
Depth accuracy is crucial in cased hole logging and wireline services oil and gas. A mismatch in the measuring wheel can lead to off-depth perforations, inaccurate cased hole wireline data, and lost time in formation evaluation. This incident emphasized the importance of verifying measuring wheels before every job.
Why GEO-LOG Measuring Wheels Matter
The GEO-LOG measuring head plays a vital role in ensuring logging cable accuracy. These measuring wheels come in different sizes to match various wireline technologies and cased hole well services requirements. Each measuring head is adjustable for wear and must be fitted with the correct rim to ensure accurate depth readings.
Measuring wheels are available for line sizes such as:
- 3/16, 7/32, 1/4, 9/32 (.288), 5/16, 3/8, 7/16, and 15/32.
The last three digits of the measuring wheel rim’s part number indicate the line size, ensuring compatibility with the wireline unit.
Preventing Depth Errors in Wireline Logging
To ensure precise wireline well logging measurements, every wireline service provider should follow these best practices:
- Verify the correct measuring wheel rim for the specific line size before each job.
- Inspect the GEO-LOG measuring head for wear or misalignment.
- Cross-check depth accuracy with alternative methods, such as reference depth markers or caliper logs.
- Train personnel on the importance of measuring wheel verification in wireline services.
By following these steps, wireline companies can minimize errors and improve reliability in cased hole logging operations.
Final Thoughts on Depth Accuracy in Wireline Operations
Accuracy in wireline and perforating jobs depends on attention to detail. A simple mismatch in a GEO-LOG measuring wheel can cause significant errors, affecting perforation well placement and wireline logging data quality. Taking the time to verify measuring wheel rims before every job ensures well integrity and reduces costly mistakes in wireline services oil and gas.
A small step in wireline control systems—such as double-checking the measuring head—can make a significant difference in delivering precise wireline solutions and maintaining a strong reputation in oil field wireline services.