Statistical Process Control Charts Applied to Rock Disintegration Quality Improvement
Round 1
Reviewer 1 Report
Recommendations / suggestions
Figure 3: Add a position for the "13-sheet covering"
In Table 1, for constants B3, B5, D1 and D3, write zero (0) instead of the minus sign (-).
Conclusion
Change the existing title "Conclusion and future work or discussion (Conclusions and discussion)" to 4. "Conclusions".
The text of the Conclusion should be significantly shortened and only the conclusions arising from the conducted research should be stated. The discussion has already been presented in "3. Experimental results and discussion".
Author Response
Point 1: Figure 3: Add a position for the "13-sheet covering".
We are pleased to submit the revised manuscript based on the reviewers' comments. We appreciate the reviewers' comments and recommendations. We have revised the manuscript thoroughly and responded to each of the comments of the reviewers in this paper and have also indicated the changes to the original manuscript.
Response 1: Thanks for your suggestions. Following your suggestions, we made the appropriate modification and explanations. The Figure 3 has been revised.
We have included this response in the revised manuscript in the Theoretical background and calculation section.
Point 2: In Table 1, for constants B3, B5, D1 and D3, write zero (0) instead of the minus sign (-).
Response 2: Thanks for your suggestions. Following your suggestions, we made the appropriate modification. Tables have been renumbered. The Table 1 is now Table 5.
We have included this response in the revised manuscript in the Theoretical background and calculation section.
Point 3: Conclusion
Change the existing title "Conclusion and future work or discussion (Conclusions and discussion)" to 4. "Conclusions".
The text of the Conclusion should be significantly shortened and only the conclusions arising from the conducted research should be stated. The discussion has already been presented in "3. Experimental results and discussion".
Response 3: Thanks for your suggestions. Following your suggestions, we made the appropriate modification.
Thanks for your suggestions. Following your suggestions, we made the appropriate modification. The title of the fourth section has been revised and text of conclusion has been reduced.
Reviewer 2 Report
The article entitled "Statistical Process Control Charts Applied to Rock Disintegration Quality Improvement" is an interesting topic and is well written, with careful writing. However, it is a bit lacking in content; I would suggest to be considered as technical note.
Some comments can help to improve the article:
- A more complete investigation should be shown, where it would be interesting to provide more empirical data in different materials or in different perforations of the same material with different degrees of alteration in the ground (or different depths)
- Depth drilling logs should be included, showing drill columns in the field.
- The formulation must be condensed, which is unnecessarily repetitive between equations 5-10, 13-17, 18-21 and 23-27.
- More information should be provided to support the hypothesis of normal distribution of the measured data for the drilling process. It is said that it has been verified with a high number of data, please provide us or a reference where the hypothesis can be consulted and verified.
- For the adequate statistical treatment, the statistical significance that is considered valid in the exposed methodology must be provided.
-A further discussion would be expected regarding the relationship between the "hardness" and indirectly the resistance of the material with the drilling control parameters. This discussion is highly recommended and is especially relevant in rock mechanics. It could be done for the same material in different conditions of alteration or depth. Andesite is a good material to carry out this discussion and to be able to obtain useful parameters later for engineering designs.
Author Response
Point 1: The article entitled "Statistical Process Control Charts Applied to Rock Disintegration Quality Improvement" is an interesting topic and is well written, with careful writing. However, it is a bit lacking in content; I would suggest to be considered as technical note. Some comments can help to improve the article:
A more complete investigation should be shown, where it would be interesting to provide more empirical data in different materials or in different perforations of the same material with different degrees of alteration in the ground (or different depths).
Response 1: Thanks for your suggestions. Following your recommendations, we made the appropriate modification and explanations. Rotary disintegration is carried out on rocks andesite, granite, limestone. The operating modes for the revolutions parameter can be set to n = 800 (rpm), n = 1000 (rpm), n = 1200 (rpm), n = 1400 (rpm), and for the pressure force F = 5000 (N), F = 8000 (N), F = 10000 (N), and F = 12000 (N). Possible adjustable variants of operating modes are shown in Fig. 6.
We have included this response in the revised manuscript in the Theoretical background and calculation section.
Point 2: Depth drilling logs should be included, showing drill columns in the field.
Response 2: Thanks for your suggestions. Following your suggestions, we made the appropriate modification and explanations.
During the drilling process, several parameters that define this process are measured and recorded. However, they are not examined to determine statistical process control. A complete overview of the measured parameters and their values are shown in Tab. 1.
We have included this response in the revised manuscript in the Theoretical background and calculation section.
Point 3: The formulation must be condensed, which is unnecessarily repetitive between equations 5-10, 13-17, 18-21 and 23-27.
Response 3: Thanks for your suggestions. Following your suggestions, we made the appropriate modification and explanations.
The presented equations must be for the continuity of the calculations. Repeating text between equations have been reduced.
We have included this response in the revised manuscript in the Theoretical background and calculation section.
Point 4: More information should be provided to support the hypothesis of normal distribution of the measured data for the drilling process. It is said that it has been verified with a high number of data, please provide us or a reference where the hypothesis can be consulted and verified.
Response 4: Thanks for your suggestions. Following your recommendations, we made the appropriate modification and explanations.
The normal distribution is understood as a mathematical model of the empirical distribution of values, which can be used to analyze, explain, and implement results obtained from various measured technological parameters under comparable conditions. Deviations from the actual value are affected only by chance. A typical theoretical distribution is the Gaussian normal distribution. Its graphic representation is a bell-shaped Gaussian curve.
Gaussian curves of the normal distribution were constructed and plotted in histograms for input and output technological parameters to support the normal distribution hypothesis. The references that confirm the hypothesis of a normal distribution are as follows [54-58].
We have included this response in the revised manuscript in the Experimental results and analysis section. Also the list of references has been updated.
Point 5: For adequate statistical treatment, the statistical significance that is considered valid in the exposed methodology must be provided.
Response 5: Thanks for your suggestions. Following your recommendations, we made the appropriate modification and explanations.
The control diagrams assume a theoretical probability of p = 99.73 % and uncertainty of α=0.27 %. As exceeding regulatory limits is considered an exceptional phenomenon in terms of probability, the process must be intervened immediately in the event of its occurrence.
We have included this response in the revised manuscript in the Experimental results and analysis section.
Point 6: A further discussion would be expected regarding the relationship between the "hardness" and indirectly the resistance of the material with the drilling control parameters. This discussion is highly recommended and is especially relevant in rock mechanics. It could be done for the same material in different conditions of alteration or depth. Andesite is a good material to carry out this discussion and to be able to obtain useful parameters later for engineering designs.
Response 6: Thanks for your suggestions. Following your recommendations, we made the appropriate modification and explanations.
Rock hardness is one of the longest-used properties for rock classification. Hardness is understood as the rock's mechanical property, expressed by the resistance to deformation of its surface, caused by the action of a foreign body.
Rock hardness as a mechanical property is not a physical quantity because this value depends more than any other mechanical property on the rock's complex surface properties under test and on the test conditions under which the hardness is determined.
During the hardness test, the test material's surface is mechanically loaded by the pressure of a foreign body, and the result of this action is quantified as the hardness value. It follows that the hardness of the rock is a technical-mechanical property that has a conventional character. This conventionality is determined by the defined test procedure and test conditions.
Hardness and strength represent the properties of the rock characterizing their resistance to external forces' mechanical action. Simultaneously, the strength expresses the resistance of the whole body against the breaking of the whole volume by dividing the rock into parts. Hardness represents the body's resistance to the action of concentrated forces, not sufficient for complete disintegration, but causing partial local failure or deformation.
Andesite rock was selected to assess the stability of the drilling process. During its rotary disintegration, there was a significant instability of the process. Rotational disintegration of andesite was a motivating factor for this study.
Tables (2-4) show the significant geomechanical properties that are observed during the rotary disintegration of the rocks. In the present issue, this is understood as uncontrollable process input parameters. Their fundamental influence is a separate subject of research and study.
Direct research of the dependence between hardness and control parameters of rotational rock disintegration has not been carried out. This promising idea will be the subject of future research.
The new table (see Tab. 2-4) was added to the manuscript.
We have included this response in the revised manuscript in the Theoretical background and calculation section.
Round 2
Reviewer 2 Report
OK. The authors have introduced comments.
