Experimental Study on the Effect of Temperature on the Characteristics of Cutterhead Mud Cake in Complex Red-Bed Geology
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsCoatings Review
July 29, 2024
The authors provide a detailed analysis of the formation of mudcake on the cutting face of drilling machines. The presentation is generally clear, and the illustrations are excellent.
I suggest that the “Engineering Background” suggestion should be listed s a separate entity, not included as part of the “Materials and Methods” section. The methods description needs to include a mention of the instrument that was used for laser particle analysis, e.g., listing a model number & manufacturer. Was the drilling simulation apparatus constructed by the authors, or obtained from an outside source?
Otherwise, my comments refer to very minor wording issues.
Line 17: However, temperatures above 150°C promote sintering of the mud cake, reducing their shedding efficiency.
Comment: Wording needs some adjustment. In present form, there is a singular/plural mismatch between “mud cake” and “their shedding efficiency”
Line 18: The hardness of the mud cake increases with temperature, particularly at high temperatures (above 150°C)
Comment: I suggest “The hardness of the mud cake increases with temperatures above 150°C”,
Line 22: reaching its minimum at 22 about 30%
Comment: Is this weight% or volume%?
Line 33:
The mud cake attached to the cutterhead, under the influence of geological pressure and temperature at the cutter face, tend to consolidate
Comment: “mud cake” is again being used as a plural term, as evidenced by the “tend to” verb. This grammatical issue needs to be reconsidered.
Line 40: Thewes et al. [4] have refined the mud cake issue into an interplay of four single-effect mechanisms,
Comment: Perhaps this could be “Thewes et al. [4] have defined the mud cake issue as an interplay of four single-effect mechanisms”
Line 45: when the clay content in the layer 45 exceeds 25%,
Comment: Percent is an imprecise term, it can be weight %, volume %, or numerical %.
Line 78: When geological hardening or mud cake formation occurs
Comment: I presume you mean that when drilling encounters harder geological strata, not that the rock becomes harder because of the drilling process. The clarity of this statement can be improved.
Line 90: Red-bed geology consists of iron-rich sedimentary rock layers with clay minerals as the primary component
Comment: I suggest “Red-beds consist of iron-rich sedimentary rock layers with clay minerals as the primary component”
Line 130: Should be “Experimental Materials”
Line 248: Hardness tests will be conducted on samples baked for 50 minutes at temperatures of 25°C, 50°C, 75°C, 100°C, and 125°C
Comment: The analyses have been completed, so this statement should be past tense, e.g., “were conducted”.
Figure 2: The labels “upper soft lower hard” are unclear, because they are shown on a horizontal axis that does not show vertical stratigraphic position.
Line 150: The high content of silt and clay particles in the mud cake makes it easy for mud cake to form on the cutter tools and cutter head
Comment: Here is an example where “mud cake” is used as a singular term.
Also, I’m not sure about the “easy” description”. Perhaps a preferable wording is “The high content of silt and clay particles in the sediment causes mud cake to rapidly form on the cutter tools and cutter head”
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsCongratulations for your excellent work. I would have some minor comments before publication. It would be interesting to mention some recommendations for applications, derived by this study. Furthermore, in Figure 12 it seems to me that a concept of an activation energy in combination with a sigmoid curve could apply to theoretically describe the FSA as a function of temperature and time. Finally, please correct in Figure 23 the caption and the legend from Foece to Force.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for Authors
A paper submitted seems to be well structured and written although it is rather long for as single research paper. Background and scope of research is clear and summarized well in introduction. Discussion and the proposed conceptual model for adhesion mechanism of soil particles on the cutter head are based on the well-controlled experimental results noted in the manuscript. It is therefore that the reviewer recommends for accepting as the minor revision considering the following specific minor comments.
Figure 1: Should be add the scale on the figure. Inserted figures in the middle part (i.e, figure showing the cross sections) are not clear and too small. It should be clear.
Figure 2: Should be shown the scale on the figure. The area showing the tunnel seems to be quite large and it does not seem to be consistent with the real scale, should be checked carefully. Legend noted on the bottom of figure is invisible and should be clear.
Figure 5: Title should be corrected as “The flowchart of the experimental methods”. Description of line 176 is also corrected. Recommend enlarging the figure since it is not easy to read.
Line 253: Better to add a short description of the specification of pressure sensor (e.g., product name, model number etc.) for traceability.
Line 281: The reason why the authors used pure water for the experiments would be preferable since there would be possibility that the saline water may cause the different results.
Figure 12, Figure 17, Figure 20 and Figure 21: Not clear for the characters on the figures. Should be enlarged for visible.
Figure 29: An interesting story for interpretation of the results.
Line 556: Should be confirmed the number “679%” in this sentence whether it is correct.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
