Rolling Eccentric Steel Rings on an Industrial Radial–Axial Ring Rolling Mill

Round 1

Reviewer 1 Report

think it is a fine paper - it could be of interest to have more information on tool geometry, process settings and control - and also the related FE-modelling - that may be the base for another article

Considering the paper it is primarily a contribution to expanding general process knowledge - another point of view (more academic, narrow) could have been chosen focusing e.g. on FEA and/or (dynamic) control of the process.

Author Response

Thank you for your comments. See statements attached.

Author Response File: Author Response.pdf

Reviewer 2 Report

The article presents an interesting concept of eccentric ring manufacturing trying to avoid traditional drawbacks of the process. It was prepared carefully from the editorial point of view. The quality of graphics, charts and tables leaves little to be desired, hence the concepts are clearly shown. The literature review was conducted reliably; however, the number of literature positions recalled was not impressive. There are a few questions/ambiguities about the terminology, methods, and assumptions adopted addressed to the authors. Finally, the article needs some language polishing since some inaccuracies in English usage were found.

Remarks/questions.

1. Description of the Figure 4

Drawing is believed to be the primary tool engineers use to exchange information. The description of figures from a scientific point of view can also be critical for explaining certain phenomena. That is why it is essential to describe charts or drawings clearly. In Figure 4, it seems evident that the starting point of the chart corresponds to the which point in the figure on the right. However, this should be indicated for unambiguity and the direction of rotation to which the characteristics correspond. By the way, it seems that a good tradition is in multi-element drawings, like Fig.4, describe individual parts by A, B, C, ... or 1,2,3, .... or A1, A2, A3,. .. or similarly, and refer to these markings in the text instead of using the terms "on the left", "on the bottom of the drawing", etc.

2. Line 147

There is no comment/explanation why the tool's temperature in the FEM model is set at 200C. Also, as they are rigid (no mesh, just geometry), a particular procedure must be used to enable heat exchange, correct?

3. Table 2
A number of elements - is it the final step mesh state amount, average during simulation or initial?

The primary mechanism of heat flow/exchange when two bodies touch each other is conductivity. How does the emissivity parameter relate to that?

Mass scaling is an artificial parameter. How was it set/established to work correctly with the model?

The yield stress is a specific value. The authors did not provide this data for ST37-2 steel in the table; only very general characteristics indicated the flow curve. The curves presented in Fig.7. suggest that yield stress is slightly above 25 MPa, depending on the testing temperature.

4. No information about any optimization procedure applied according to mesh density influences the results.

5. There is a lack of boundary conditions in the FEM model. It could be symbolically presented in Fig. 6, for example. Without this information it is impossoible to relicate the FEM model.

Language - general remarks

The journal cares for a high level of both science and language. The relatively minor language errors indicate that the text has yet to be subjected to critical language analysis. It can be essential in the case of non-English readers because, very often, the effect of such neglect is a misunderstanding by the reader/reviewer of the appropriate, substantive content of the article. Most of the indicated errors or inaccuracies can be efficiently corrected by automatic language correction engines available at the level of the text editor. However, of course, nothing can be replaced by a native speaker. Also, there are minor typo errors. Examples are taken only from the abstract and Introduction.


Detailed remarks


Abstract

Line 15
The oil-clay does not seem to fit the context. Consider replacing with "oil clay".

Line 18
The objective of this paper is to demonstrate the basic feasibility on an industrial radial-axial ring rolling mill.

The objective of this paper is to demonstrate the basic feasibility OF THE METHOD/CONCEPT on an industrial radial-axial ring rolling mill.

Line 19
In a first step, FEA-simulation studies were carried out to develop the rolling strategy and to estimate ...

Suggestion: remove TO before estimate
In a first step, FEA-simulation studies were carried out to develop the rolling strategy and estimate ...

Line 20
...institute's own radial-axial ring mill.

Suggestion: remove OWN
...institute's radial-axial ring mill.

Line 21
Subsequently, the rolling strategy was implemented on the industrial ring rolling mill with the help of a special technology ...

Suggestion: word SPECIAL is often overused. Try PARTICULAR, UNIQUE, ...

Line 22
Finally, an eccentric ring was ring rolled and compared with FEA simulation and the reproducibility was demonstrated successful.

This sentence may contain incorrect or awkward phrasing. Consider changing:
Finally, an eccentric ring was rolled and compared with THE FEA simulation, and the reproducibility was demonstrated TO BE successful.


Introduction

Line 38
Eccentric rings could be used e.g. in triple ring eccentric bearings (cf. Fig. 1).

Comma is missed:
Eccentric rings could be used, e.g. in triple ring eccentric bearings (cf. Fig. 1).

Line 39
The material savings to be achieved and thus also the energy savings depend on the wall thickness difference between the thickest and thinnest wall thickness.

Suggestion:
The material savings to be achieved and, thus, the energy savings depend on the thickness difference between the thickest and thinnest wall thickness.

Line 46
Today, eccentric rings can either be machined from a solid ring, open die forged or
casted.
 
'Either... or' is a conjunction used in sentences relating to a choice between two possibilities. So, in this sentence it is better for clarity to remove it.

Today, eccentric rings can be machined from a solid ring, open die forged or casted.

Line 47
However, each of these processes offers its own disadvantages, ...

It seems to be redundant. Suggestion: remove OWN
However, each of these processes offers its disadvantages, ...

Line 50
Therefore, a high potential for material and energy savings while meeting the customer's product-specific mechanical requirements arises.

Consider rephrasing:
Therefore, a high potential for material and energy savings arises while meeting the customer's product-specific mechanical requirements.

Line 53
...i.e. for changing tools, and with material and energy costs savings.

It sgould be rather similar:
...i.e. for changing tools, and with material and energy COST savings.

Line 55
...must be moved dynamically based on the rings current position rotation angle to narrow...

It seems that the noun RING form may be incorrect. Suggestion:

...must be moved dynamically based on the RING'S current position ...

Line 65
Furthermore the sensing was simplified.

Consider adding a comma:
Furthermore, the sensing was simplified.

Line 66
So that the radial roll pair, meaning mandrel and main roll, where moved to keep the ring in the centre of the mill remaining stationary along the x-axis [9] to measure the current state of the ring geometry by tracking marks on the rings top surface by an USB web camera [11].

This sentence is hard to follow and contains a few spelling, grammar and punctation mistakes. Please, rewrite it.

Line 69
But, on industrial radial-axial ring rolling mills,...

Suggestion:
HOWEVER, on industrial radial-axial ring rolling mills,

Line 69
...there's a notable obstruction in viewing ...

It is rahter informal writing. Suggestion:
... THERE IS a notable obstruction in viewing ...

Line 69
But, on industrial radial-axial ring rolling mills, there's a notable 69
obstruction in viewing the ring caused by the tight closure of the.

It looks that there is sth missing at the end of the sentence.

Line 73
To control the mandrel at the right time and feed the mandrel dynamically in the main rolls direction or backwards, the current state of wall thickness in the radial roll gap must be known at any time while ring rolling.

It is hard to follow the sentence. At first, "To control the mandrel at the right time and feed the mandrel dynamically in the main rolls direction or backwards" does not appear to be modyfying the subject "the current state of wall thickness in the radial roll gap". Rewrite the sentence for better understanding.

Line 73
... rolls direction ...

Suggestion: ... roll's direction ...

Line 78
This opened up the possibility to adjust the...

Suggestion:
IT opened up the possibility to adjust the...

Line 78
...the mandrels position...

Suggestion:
...the mandrel's position...

Author Response

Thank you for your comments. See statements attached.

Author Response File: Author Response.pdf

Reviewer 3 Report

A novel ring rolling strategy for producing eccentric ring was proposed in this study. The effects of rolling processing parameters on the forming characteristics of the eccentric ring are discussed. The results are interesting and useful in industry. However, several flaws should be improved to be published in Materials.

(1)    The innovation of this investigation should be clarified in the introduction.

(2)    As discussed in sections 3.2 and 4.2, the experimental results are analyzed in detailed. However, the metallurgical mechanism and theoretical analysis about the experimental results are lacking.

(3)    Only the Marco forming behavior of the eccentric ring was investigated, the influences of ring rolling parameters upon the microstructures and properties are lacking.

(4)    The words and grammar in present study are needed to be promoted.

Major editing of English language is required.

Author Response

Thank you for your comments. See statements attached.

Author Response File: Author Response.pdf

Reviewer 4 Report

Dear Authors,

The paper is interesting, but I have some questions/comments.

1. The purpose of the paper and its significance should be described in more detail to help improve the discussion of results.

2. The quality of figure 1 needs to be improved, a better resolution (minimum 600 dpi) is required.

3. How do the authors explain the wall thickness variations (thickenings and thinnings) of the rings during the rolling process (see Figures 8 and 10).

4. In the rolling process, the volume of material remains constant. In this sense, how do the authors explain the results shown in table 5. While the deviation between simulation and experiment is less than 1% for all dimensions (D₀, D_i, s_min, s_max, h), except for the eccentricity e, which deviation is more than 6 times higher?

5. A clearer highlighting of the conclusions should be made. The conclusions seem more like a summary of the results presented in section 4.

Author Response

Thank you for your comments. See statements attached.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

No further comments.