Internal Gas-Assisted Mold Temperature Control for Improving the Filling Ability of Polyamide 6 + 30% Glass Fiber in the Micro-Injection Molding Process
Round 1
Reviewer 1 Report
In this article, a pre-heating step with the internal gas heating method was used to heat the cavity surface to a high temperature before the filling step to reduce the frozen layer and to improve the filling ability of the composite material (polyamide 6 + 30% glass fiber) in the micro-injection molding process. The internal gas-assisted mold temperature control (In-GMTC) was established with different insert thicknesses (t) and gaps between the gas gate and heating surface (G) to achieve fast mold surface temperature control. Then, along with the local gate temperature control, the In-GMTC was used for the thin-wall injection molding cycle. The heating process was clearly affected by the stamp thickness, a thinner stamp providing a higher heating rate with a small heating area. The use of the In-GMTC for a real molding cycle demonstrated that the melt flow length improves significantly when the In-GMTC was used at the melt gate.
Overall, the article is well-written, experimental data of real significance are clearly presented and discussed in relation with previous works on the topic. The references section is appropriate. I recommend its publication in its present form.
Author Response
Dear Reviewer,
Thank you for your letter and constructive comments concerning our manuscript entitled “Internal Gas-Assisted Mold Temperature Control for Improving the Filling Ability of Polyamide 6 + 30% Glass Fiber in Micro-Injection Molding Process”. We have some minor modification of our paper to make it clearer as:
- A short summary about the new design of In-GMTC was add at the end of “Introduction” part
- The system description was separated into a new part
- The simulation also separated into a new part.
- Figure 5 was modified with the cavity dimension could be read clearly
One more time, thank you very much for your comment.
Yours Sincerely,
PHAM SON MINH
HCMC University of Technology and Education, Hochiminh city, Vietnam
No 1 Vo Van Ngan Street, Linh Chieu Ward, Thu Duc District, Ho Chi Minh City, Vietnam
Room E1.202
Phone No: +84-(938)-226313
E-mail: minhps@hcmute.edu.vn
Author Response File: 
Author Response.pdf
Reviewer 2 Report
“Internal Gas-Assisted Mold Temperature Control for Improving the Filling Ability of Polyamide 6 + 30% Glass Fiber in Micro-Injection Molding Process“ examines both with simulations and experimentally the improvement achieved in micro injection molding by the use of a internal gas-assisted mold temperature control at the variation of sensible parameters of the system.
Revision or comment
The work is in a very broad and interesting field of the injection molding process. It examines the proposed issue with simulations and hence with an experimental validation of suggested simulation results. Methodological approach is correct even if some considerations about the standard deviations shown in figure 13 and 15 are missing. In figure 18 there are no errors, they should be indicated.
I suggest a better organization of the paper to make it clearer.
The introduction ends with the description of the system used by authors for their work (from line 101). It would be better that introduction ends with a very short summary about what will be presented in the paper. The system should be described in the next section about system and methods. Also, simulation should be better presented in a specific section. Then experimental part, results and discussion.
Authors are invited to inspect the paper for minor revisions like that follow and to check for English language:
Line 168: cavity dimensions are not clear in its section (figure 5).
Line 270: is the sensor latency so high? however, in spite of the bias, data seem consistent.
Author Response
Dear Reviewer,
Thank you for your letter and constructive comments concerning our manuscript entitled “Internal Gas-Assisted Mold Temperature Control for Improving the Filling Ability of Polyamide 6 + 30% Glass Fiber in Micro-Injection Molding Process”. We have studied your comments carefully and made revisions that we hope meet will with your approval. The modification was highlighted with the note in the manuscript. Here are our responses (your comments are in highlighted bold italics):
(*) The introduction ends with the description of the system used by authors for their work (from line 101). It would be better that introduction ends with a very short summary about what will be presented in the paper. The system should be described in the next section about system and methods. Also, simulation should be better presented in a specific section. Then experimental part, results and discussion.
--> Thank you very much for your comments. The modification had been made with:
- A short summary about the new design of In-GMTC was add at the end of “Introduction” part
- The system description was separated into a new part
- The simulation also separated into a new part.
(*) Line 168: cavity dimensions are not clear in its section (figure 5).
--> Figure 5 was modified with the cavity dimension could be read clearly
(*) Line 270: is the sensor latency so high? however, in spite of the bias, data seem consistent.
--> Actually, in this experiment, the temperature difference is smaller than 5 °C, this is due to the latency of thermal camera, as well as the waiting time for the camera catching the temperature result. Maybe, this difference is still high when we compare with other measuring equipment. However, in injection molding field, this difference is still accepted. However, we agree with your comment, the latency should be reduced by accuracy equipment. We hope that, in our next research, we could have a better equipment for measuring the temperature.
We sincerely hope that these modification meet your approval.
Thank you very much for your advices.
Yours Sincerely,
PHAM SON MINH
HCMC University of Technology and Education, Hochiminh city, Vietnam
No 1 Vo Van Ngan Street, Linh Chieu Ward, Thu Duc District, Ho Chi Minh City, Vietnam
Room E1.202
Phone No: +84-(938)-226313
E-mail: minhps@hcmute.edu.vn
Author Response File: Author Response.pdf
