Calculating Method for the Axial Force of Washover String During Extracting Casing in Directional Well
Bibliographic record
Abstract
In the process of extracting casing in directional well, the existence of inner casing and external centralizer makes the calculation of washover-string axial force more complex, which increases the difficulties for choosing a reasonable bit weight in construction with no doubt. In this paper, through taking three factors of casing contacting with washover tubing, centralizer and washover tubing contacting with well wall into consideration, an effective method for calculating the axial force conducting is established. Moreover, the axial force in different conditions is obtained through numerical solution. The calculation results are: (a) The casing has a less effect on the axial force conducting, and the axial force loss is mainly at centralizers and new contact points. (b) The axial force conducting can be improved effectively through setting a reasonable centralizer spacing. There is no doubt that the establishment of the method has an important significance for choosing the bit weight, judging whether the washover head cuts casing and designing washover string. Key words: Axial force; Washover string; Extracting casing; Frictional resistance
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".