# Determination of the Depth of Cut via Surface Integrity
## 5 Conclusions  
The present paper falls within process planning and machining process optimization. In this way, the approaches from the paper are aimed at the automatic establishment of routing sheets and a novel modality for calculating the depths of cut. The main conclusions are presented as follows:  
1. The quality of the machined surface must not be reduced only to the surface roughness;
2. Surface integrity is a very important indicator for the assessment of the machined-surface quality, and it is directly related to the performance of a product;
3. The surface integrity influences the depth of cut. This means that the material layer having the thickness of the depth of cut must contain all the errors obtained in the surface and subsurface layers in the case of the previous machining operation. This fact is ensured by relations (2)-(16) conceived by the authors;
4. Determining the depth of cut requires knowledge of the routing sheet. For the routing sheet, the decisional element is the roughness of the surface to be machined;
5. After the routing sheet is known, the CDFTCI software tool calculates the depth of cut for every technological sequence. In this case, the decisional element is surface integrity;
6. The present paper leads to a novel approach to machining parameters optimization. First of all, the depths of cut must be calculated in accordance with ensuring the surfaces integrity. Then, the results obtained in this manner must be integrated into mathematical models for machining parameters optimization (into the objective function or/and as constraints);
7. The novelty of the present paper refers to the use of the surface integrity concept for establishing the routing sheet and the related depths of cut for turning the front faces of cast iron work pieces. In this way, the authors have developed a new/original software tool named CDFTCI (conceived in Delphi environment). This software isbased on a small database associated with the original mathematical relations (2)-(16), whose role is to model the components of surface integrity and other errors; (h) The CDFTCI software also contributes to the calculation of the billets' dimensions regarding the front faces; with respect to the calculation of the billets' dimensions regarding the cylindrical surfaces, TESEQ and CDCIM software tools must be used [8]; (i) The CDFTCI software tool could be used as a standalone application, and it might be easily integrated into any CAP system and translated, if necessary, into other programming languages.  
All authors contributed to the elaboration of this paper. Conceptualization, C.G. and N.-V.I; methodology, C.G. and N.-V.I; software, N.-V.I. and G.O.; validation, C.G., N.-V.I. and G.O.; formal analysis, C.G. and N.-V.I; investigation, C.G., N.-V.I. and G.O.; resources, C.G. and G.O.; data curation, C.G., N.-V.I. and G.O.; writing--original draft preparation, N.-V.I.; writing--review and editing, C.G., N.-V.I. and G.O.; visualization, C.G. and G.O.; supervision, N.-V.I. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
The authors declare