CNC Machining Strategies (FSI-GSC)

Academic year 2022/2023
Supervisor: Ing. Aleš Polzer, Ph.D.  
Supervising institute: ÚVSSR all courses guaranted by this institute
Teaching language: Czech
Aims of the course unit:

The main goal of the course is to deepen practical knowledge and experience in controlling selected CAD and CAM software, control system (Sinumerik) CNC machines and specialized contact or optical measuring instruments controlled by their specialized software (eg: CCI optical roughness tester from Taylor Hobson, optical SOL 311 profilometer from Micro-Vu, contact 3D coordinate measuring machine).

Learning outcomes and competences:

The graduate's ability to appropriately choose machining strategies on CNC machines with regard to machine design (performance parameters, machine kinematics, etc.) and with regard to the quality of the resulting workpiece (integrity of the machined surface, etc.).

Prerequisites:

Basics of technical drawing.

Course contents:

The course is designed as a combination of knowledge of the basics of machine tool design, production on CNC machining centers and measurement of workpiece parameters.

The basics of design performed in CAD software are applied to simple examples of workpiece parts. Increased emphasis is placed on the technological design with respect to machining in CAM software. Differences in usable strategies and procedures in machining are evaluated in terms of the integrity of machined surfaces and the overall quality of products.

Teaching methods and criteria:

Teaching in exercises and in labs is realized with the support of modern computer technology: specialized SW and HW.

Assesment methods and criteria linked to learning outcomes:

A graded credit will be awarded on the basis of the achieved results of independently performed tasks (eg: design, NC programming, measurement) in exercises / laboratories.

The final exam will test theoretical and practical knowledge of the subject matter: in the form of a brief test (5-10 questions) and individual work (30-60 min) in CAD, CAM or Sinumerik control system of the machine tool.

Controlled participation in lessons:

Student participation in exercises and laboratories is mandatory and checked regularly. Missed exercises / laboratories can be replaced by processing, for example, a brief search on a given topic (details consulted with the teacher in advance). A maximum of four unexcused / unreplaced absences per semester are allowed.

Type of course unit:
    Laboratory exercise  13 × 2 hrs. compulsory                  
    Exercise  13 × 2 hrs. compulsory                  
Course curriculum:
    Laboratory exercise

  1. Basic technological calculations of cutting forces, application to a CNC machine tool.

  2. Basic technological calculations of cutting forces, application to a CNC machine tool.

  3. Machining tools.

  4. Determination of cutting conditions for machining.

  5. Calculation of cutting forces and machinability.

  6. Technological procedure of machining a specific part.

  7. Technological procedure of machining a specific part.

  8. Technological procedure of machining a specific part.

  9. Technological procedure of machining a specific part.

  10. Technological procedure of machining a specific part.

  11. Workpiece surface integrity.

  12. Workpiece surface integrity.

  13. Machining demonstration. 

    Exercise

  1. Division of machined and cutting materials, machinability.

  2. Cutting forces for individual machining operations, their analytical calculation, force flow through the machine tool.

  3. Methods of clamping tools and workpieces on CNC machine tools, principles and influence on machine loading.

  4. Origin of self-excited oscillations during machining, technological ways of limiting its occurrence.

  5. Machining strategies for machining non-rotating workpieces on milling centers with a vertical spindle axis.

  6. Machining strategies for machining non-rotating workpieces on milling machining centers with a horizontal spindle axis.

  7. Machining strategies for machining non-rotating workpieces on portal machining centers.

  8. Machining strategies for machining workpieces on milling multifunctional machining centers.

  9. Machining strategies for machining rotary workpieces on turning centers with horizontal and vertical spindle axis.

  10. Machining strategies for machining rotary workpieces on multifunctional turning machining centers.

  11. Machining strategies on horizontal boring machines.

  12. Machining strategies on grinding machines.

  13. Heavy workpiece machining strategy.

Literature - fundamental:
1. MAREK, Jiří. Konstrukce CNC obráběcích strojů IV.0. Praha: MM publishing, 2018. MM speciál. ISBN 978-80-906310-8-3.
2. PETR, Karel. Geometrické tolerance dle ISO GPS. Praha: Verlag Dashöfer, 2019. ISBN 978-80-7635-019-9.
3. CNC4you: CNC practical knowledge for production, job shop and production planning. CNC4you [online]. Germany: Siemens, 2022 [cit. 2022-01-03]. Dostupné z: https://new.siemens.com/global/en/markets/machinebuilding/machine-tools/cnc4you.html
The study programmes with the given course:
Programme Study form Branch Spec. Final classification   Course-unit credits     Obligation     Level     Year     Semester  
CŽV full-time study CZV Bases of Mechanical Engineering -- GCr 4 Compulsory-optional 1 1 S
N-VSR-P full-time study --- no specialisation -- GCr 4 Compulsory-optional 2 1 S