Determination of Energy Losses of the Crank Press Mechanism

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This paper conducts the energy loss of slider-crank mechanism. This manuscript is suitable to the scopes and objectives of this journal. However, I recommend the major revise.

 

1. The organization of manuscript is terrible and the chapter should be improved. The abstract needs to be improved with more critical information and important findings. In introduction, many studies are only listed. There is not any detailed description.

 

2. The contact and friction play the important role of mechanism, which is also the element of energy loss. The damping characteristics and deformation cannot be considered in the simulation model. What is the value of friction coefficient? The reason should be expressed.

 

3. In fact, the clearance is given in the revolute joint and translational joint. However, it is ignored in the study. It should be considered in the energy loss.

 

4. The solution of simulation model cannot be given in detail.

 

5. The effects of parameters for proposed model on the dynamic cannot be discussed in detail, which is the foundation of suitable condition.

 

6. Beyond this, it has to be mentioned that the language problems are dramatic. There are many semantic problems such that the text is partly incomrehensible.

 

Comments on the Quality of English Language

Beyond this, it has to be mentioned that the language problems are dramatic. There are many semantic problems such that the text is partly incomrehensible. 

Author Response

Thank you very much for taking the time to review our manuscript. Your review is not very pleasing, but we agree with it. We have tried to improve our article.

Comments 1: The organization of manuscript is terrible and the chapter should be improved. The abstract needs to be improved with more critical information and important findings. In introduction, many studies are only listed. There is not any detailed description.

Response 1: We have tried to describe the order of the chapters in Chapter 1. Introduction. The logic is such that in Chapter 2 we describe the basic relationships that will be used later. In Chapter 3 we define the initial parameters (for a real forging press) for the subsequent calculations. Chapters 4 to 7 are devoted to the various methods of friction loss determination. Chapters 8 and 9 are the conclusion of the thesis.

Comments 2: The contact and friction play the important role of mechanism, which is also the element of energy loss. The damping characteristics and deformation cannot be considered in the simulation model. What is the value of friction coefficient? The reason should be expressed.

Comments 3: In fact, the clearance is given in the revolute joint and translational joint. However, it is ignored in the study. It should be considered in the energy loss.

Response 2 + 3: In Chapter 2.2.1 Coefficient of Friction we described the approach to the coefficient of friction. We are aware that it can be considered functionally dependent. Since the simplest methods of friction loss calculation cannot handle a dependent coefficient of friction, a constant coefficient of friction is used even in more advanced methods. For the same reason, the effect of damping and clearances in the mechanism are not taken into account. A real forging press uses an efficient method to define the clearances in the crank mechanism, so there should be no clearances at all (yes, reality may be different).

Comments 4: The solution of simulation model cannot be given in detail.

Response 4: The presented Multibody simulation result for the whole stroke is used to demonstrate the simulation capabilities. As the resulting friction loss values would be higher than those obtained by the previous methods, both the results for the full stroke and for the part of the process operation itself are shown in Table 8.

Comments 5: The effects of parameters for proposed model on the dynamic cannot be discussed in detail, which is the foundation of suitable condition.

Response 5: In the Multibody simulation, a low crankshaft speed condition was used (can be derived from Figure 12). Yes, it does not correspond to reality. This condition was used for backward compatibility with previous methods. In fact, we also have multibody simulation results where the speed is not constant (depending on the flywheel energy and the energy consumption). However, we plan to use these results in a future publication that does not aim to compare multiple methods.

Comments 6: Beyond this, it has to be mentioned that the language problems are dramatic. There are many semantic problems such that the text is partly incomrehensible.

Response 6: Thank you for pointing this out. We asked a colleague whose mother tongue is English and he revised our text considerably.

Reviewer 2 Report

Comments and Suggestions for Authors

The paper presents four methods of evaluation friction losses in a crank press mechanism. Mathematical model is presented for each method.

 The paper needs minor corrections:

Eqs. 1 to 8 - Measurement units should not be placed in Equations or when defining parameters, where they are not relevant. They are not relevant since the measurement units presented later in the paper are not the same.

Line 185 - Time should be measured in sec.

Author Response

Thank you very much for taking the time to review this manuscript.

Comments 1: Eqs. 1 to 8 - Measurement units should not be placed in Equations or when defining parameters, where they are not relevant. They are not relevant since the measurement units presented later in the paper are not the same.

Response 1: Thank you for pointing this out. Units were deleted.

Comments 2: Line 185 - Time should be measured in sec.

Response 2: Thank you for pointing this out. We have used the abbreviation we use in our native language (s) because it is the SI base unit. The mention of time has been removed as it was not relevant to the article.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

All questions have been revised.