Design and Technological Aspects of Integrating Multi-Blade Machining and Surface Hardening on a Single Machine Base

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript presented a hybrid machine tool system and an appropriate combined technology for manufacturing machine parts. The experimental results indicated multi advantages could be realized, conclude the increasing in processing productivity, elimination of the possibility of defects during finishing grinding, reducing of auxiliary and preparatory-final time, and reducing of interoperational backlogs of parts. The presented contents would be helpful to readers in this fields, and could be accepted for publication after minor revision addressed.

1. The abstract section should be refined to highlight the research methods and the conclusions.

2. Although it is also mentioned in the introduction section, the innovation points need to be clarified

3. Some figures can be removed, like figure 4, 6, 8, 10 and 20, which can’t provide any new knowledge to readers.

Author Response

The team of authors would like to thank the dear reviewer for taking the time to review our paper and for his valuable comments. We have tried to correct the article in accordance with these comments. The article has been revised. Therefore, if we haven't improved enough or haven't taken into account something, we are ready to finish it in a short time. Below are the responses to comments on the article. The corrected comments are highlighted in yellow in the article. The article was significantly revised, some of the text of the article was changed, and new text was added. Therefore, in the new version, corrections are made in new places and possibly on other pages.

This manuscript presented a hybrid machine tool system and an appropriate combined technology for manufacturing machine parts. The experimental results indicated multi advantages could be realised, conclude the increasing in processing productivity, elimination of the possibility of defects during finishing grinding, reducing of auxiliary and preparatory-final time, and reducing of interoperational backlogs of parts. The presented contents would be helpful to readers in these fields, and could be accepted for publication after minor revision addressed.

1 The abstract section should be refined to highlight the research methods and the conclusions.

We agree with the comment. The abstract clearly identifies the sections "Theory and Methods" and "Results and Discussion". The text of these sections in the abstract has been revised and highlighted in colour.

Theory and methods: Studies of possible structural composition and layout of hybrid equipment at integration of mechanical and surface-thermal processes have been carried out taking into account the basic provisions of structural synthesis and components of metalworking systems. Theoretical studies were carried out using the basic provisions of system analysis, geometric theory of surface formation, design of metalworking machines, methods of finite elements, mathematical and computer modelling. Mathematical modelling of thermal fields and structural-phase transformations during HEH HFC was carried out in ANSYS and SYSWELD software packages using numerical methods of solving differential equations of unsteady heat conduction (Fourier equation), carbon diffusion (2nd Fick's law) and elastic-plastic behaviour of the material. Verification of the modelling results was carried out by in-situ experiments using: optical and scanning microscopy; mechanical and X-ray methods of residual stress determination. Formtracer SV-C4500 profilograph profilometer was used in the study for simultaneous measurement of shape deviations and surface roughness. Surface topography was assessed using a Walter UHL VMM 150V instrumental microscope. The microhardness of the hardened surface layer of the parts was evaluated on a Wolpert Group 402MVD.

Results and Discussion. The original methodology of structural-kinematic analysis for pre-design studies of hybrid metalworking equipment is presented. Methodological recommendations on modernisation of multi-purpose metal-cutting machine tool are developed, implementation of which will allow to implement high-energy heating with high frequency currents (HF HFHF) on the standard machine tool system and provide formation of knowledge-intensive technological equipment with extended functional capabilities. The innovative moment of this work is the development of hybrid metalworking equipment with numerical control and writing a unique postprocessor to it, which allows to realise all functional possibilities of this machine system and the technology of combined processing as a whole. Special tooling and tools providing all necessary requirements to the process of surface hardening of HEH HFC were designed and manufactured. The conducted complex of works and approbation of the technology of integrated processing in real conditions in comparison with traditional methods of construction of technological process of parts manufacturing allowed to fix the following results: increase of productivity of processing in 1,9 times; exclusion of possibility of scrap occurrence at finishing grinding; reduction of auxiliary and preparatory-tasking time; reduction of inter-operational parts backlogs.

2. Although it is also mentioned in the introduction section, the innovation points need to be clarified

We agree with the comment. Appropriate edits have been made to the abstract, in the Results and Discussion section.

3. Some figures can be removed, like figures 4, 6, 8, 10 and 20, which can't provide any new knowledge to readers.

Yes, we agree with the comment. Figures 4, 6, 8, 10 a, 20 were removed from the text of the paper. Figure 10 b was retained in the paper because it provides an explanation of the clamping of the workpiece on one of the combined machining transitions.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This paper provided a novel hybrid machine tool system and an appropriate combined technology for manufacturing machine parts. Overall, the manuscript is well-written and explains the research clearly, I have some concerns and suggestions:

Comments for author File: Comments.pdf

Author Response

The team of authors would like to thank the dear reviewer for taking the time to review our paper and for his valuable comments. We have tried to correct the article in accordance with these comments. The article has been revised. Therefore, if we haven’t improved enough or haven’t taken into account something, we are ready to finish it in a short time. Below are the responses to comments on the article. The corrected comments are highlighted in yellow in the article. The article was significantly revised, some of the text of the article was changed, and new text was added. Therefore, in the new version, corrections are made in new places and possibly on other pages.

This paper provided a novel hybrid machine tool system and an appropriate combined technology for manufacturing machine parts. Overall, the manuscript is wellwritten and explains the research clearly, I have some concerns and suggestions:

1. Some assumptions need to be given during the simulation to simplify the calculation process, so that the reader can also easily understand the possible potential impact factors.

We agree with the comment. The section ‘Mathematical simulation of thermal fields, structural-phase transformations and the stress-strain state of a material at HEH HFC’ has undergone significant changes.

2. Figure 6 is a simple image, but there is no text description. It is recommended to add a text description, so that the reader understands the function and role of each part of the machine.

We agree with the comment. Since this figure does not present readers with any new knowledge, we have removed it from the paper.

3. In Figure 14, the surface roughness and topography should be explained in details (including the machining marks).

We agree with the comment. Appropriate explanations have been given in the text of the paper.

The following text was added to the paper:

‘As can be seen, during finishing, there is a significant improvement in the quality of the machined surface compared to the previous roughing pass. Thus, the surface roughness values are improved by a factor of almost 4. It should also be noted that at the finishing pass to increase productivity the strategy of machining ‘Raster Plane’ with alternation of counter and cross types of milling was used. The surface topography clearly shows traces of the different milling types.’

4. Figure 27(b) and Figure 27(c) were too blurry and needs to be replaced with a clearer one, and there is little difference between the two images in terms of surface profile shape, so please give a detailed explanation.

We agree with the comment. In the text of the work gave in general additional explanations for Figure 27. Due to the non-principledness of these images of surface topography, we removed them from the paper. The following text was added to the paper:

‘Analysing the data obtained, it can be found that each subsequent pass at finish grinding allows to reduce significantly the surface roughness, practically 2.53 times. At the same time, nursing for only 20 seconds allowed to further reduce the surface roughness by about 1.96 times.’

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Interesting article. The authors demonstrated their engineering expertise in expanding an existing machining station. The methodology and manner of the research conform to standards in their planning and conduct of research. However, the quality of quite several drawings deviates significantly from the norms. They are characterized by poor quality which makes them unclear. This aspect needs improvement.

The bibliography is strongly expanded, properly selected, and cited. Notes are pledged below (numbers indicate lines in the pdf version of the article): 198 increase the spacing between paragraphs in Figure 2

199 Poorly visible table related to energy distribution

228 formula should have numbering on the right side, e.g. (1)

247, 257, 317, 367, 377, 387, 441, and below increase the distance between the paragraph on the figure 

331 please format the tables correctly, compress the rows and columns more

334 pattern should have numbering on the right side, e.g. (2)

345, 382 completely invisible drawing on the left side. Please replace it with a higher-resolution drawing

354, 371, 391, 393 please format the tables correctly, compress the rows and columns more

478, 483 it is worth clarifying the meaning of G-codes

496 details of drawings are invisible. Rent inserts with higher resolution

Author Response

The team of authors would like to thank the dear reviewer for taking the time to review our paper and for his valuable comments. We have tried to correct the article in accordance with these comments. The article has been revised. Therefore, if we haven't improved enough or haven't taken into account something, we are ready to finish it in a short time. Below are the responses to comments on the article. The corrected comments are highlighted in yellow in the article. The article was significantly revised, some of the text of the article was changed, and new text was added. Therefore, in the new version, corrections are made in new places and possibly on other pages.

Interesting article. The authors demonstrated their engineering expertise in expanding an existing machining station. The methodology and manner of the research conform to standards in their planning and conduct of research. However, the quality of quite several drawings deviates significantly from the norms. They are characterised by poor quality which makes them unclear. This aspect needs improvement.

The bibliography is strongly expanded, properly selected, and cited. Notes are pledged below (numbers indicate lines in the pdf version of the article): 198 increase the spacing between paragraphs in Figure 2

Corrected. The interval has been increased.

199 Poorly visible table related to energy distribution

The drawing has been completely revised. A new version of the graphic is included in the article.

228 formula should have numbering on the right side, e.g. (1)

Corrected. The formula is numbered.

247, 257, 317, 367, 377, 387, 441, and below increase the distance between the paragraphs on the figure

Fixed. The distance between paragraphs and figures has been increased.

331 please format the tables correctly, compress the rows and columns more

Corrected. Tables No. 2, 3 and 4 have been redesigned according to the template.

334 pattern should have numbering on the right side, e.g. (2)

Corrected. All formulas in the article are numbered according to the requirements.

345, 382 completely invisible drawing on the left side. Please replace it with a higher-resolution drawing

Corrected. All drawings are made in better quality.

354, 371, 391, 393 please format the tables correctly, compress the rows and columns more

Corrected. Formatted the tables according to the requirements.

478, 483 it is worth clarifying the meaning of G-codes

Corrected. Added the following text: 1. When positioning the spindle to the starting position, the program uses the function G01 - linear interpolation; 2. When positioning to the starting point at a safe height, the program uses the function G00 - rapid positioning.

496 details of drawings are invisible. Rent inserts with higher resolution

Corrected. Figures with higher resolution were inserted into the article.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

This revision has significantly improved the manuscript.I would recommend the manuscript for publication.

Author Response

The team of authors would like to thank the dear reviewer for taking the time to review our paper and for his valuable comments.