Machine construction

Academic Year 2025/2026 - Teacher: RAFFAELE BARBAGALLO

Expected Learning Outcomes

Building on the concepts acquired in Structural Mechanics and Applied Mechanics, the foundations are provided for the design and verification of components and simple mechanical systems.

The acquired skills can be applied in the fields of industry and sustainable development, in line with Goals 9 and 11 of the United Nations 2030 Agenda.

Course Structure

Frontal lessons.

Exercises on the topics of the course.

Required Prerequisites

Principles of Structural Mechanics and Applied Mechanics.

Attendance of Lessons

Mandatory class attendance (minimum 70%).

Detailed Course Content

Materials and Design Techniques: Material testing; Characteristics and selection of materials.
Loads, stresses, and strains: Ideal stresses; Beams, shear force and bending moment diagrams; Singular functions; Principle of virtual work.
Material fatigue: Cumulative damage; Wohler Curve; Miner Law; Fatigue diagrams; Thermographic method; Notch effects; Damping; Shafts and axles.
Springs: Utilization factor; Bending springs; Leaf springs on rod supports; Progressive stiffness springs; Spiral springs; Torsion springs; Conical torsion springs.
Hertz theory: Stribeck’s formula.
Gears: Tooth thickness; Minimum number of teeth; Specific sliding; Gear calculation; Modular dimensioning of gears; Bending strength calculation; Wear calculation; Dynamic correction of allowable stress; Corrected gears.
Mechanical Couplings: Interference fits; Shaft–hub interference fits; Plate–flywheel interference fits; Tabs, Keys, splined profiles.
Pipes and pressure vessels: Stress analysis; Instability.
Clutches and brakes: Flat plate clutches; Disc brakes; Cone brakes; Drum brakes.
Joints: Sleeve joint; Cylindrical joint; Sellers joint; Disc and flange couplings; Elastic couplings; Bibby coupling; Universal joint.
Rolling bearings: Types; Components; Assembly; Calculation.
Lubrication: General equations. Journal bearing.
Photoelasticity: Fundamental principles.

Exercises on the design and verification of mechanical components.

Design of a multi-stage speed reducer/increaser.

Textbook Information

1. R. Giovannozzi. Costruzione di Macchine. Patron Editore.

2. A. Risitano. Mechanical design. CRC Press.

3. R. G. Budinas, J. K. Nisbett: Shigley's Mechanical Engineering Design. McGraw-Hill.

4. Lecture notes.

Course Planning

	Subjects	Text References
1	Materials and Design Techniques	Risitano, Shigley, Lecture notes
2	Loads, stresses, and strains	Risitano, Shigley, Lecture notes
3	Material fatigue	Giovannozzi, Risitano, Shigley, Lecture notes
4	Springs	Giovannozzi, Risitano, Lecture notes
5	Hertz theory	Giovannozzi, Risitano, Lecture notes
6	Gears	Giovannozzi, Risitano, Shigley, Lecture notes
7	Mechanical Couplings	Giovannozzi, Risitano, Shigley, Lecture notes
8	Pipes and pressure vessels	Giovannozzi, Risitano, Lecture notes
9	Clutches and brakes	Risitano, Shigley, Lecture notes
10	Joints	Giovannozzi, Risitano, Lecture notes
11	Rolling bearings	Giovannozzi, Risitano, Shigley, Lecture notes
12	Lubrication	Giovannozzi, Risitano, Shigley, Lecture notes
13	Photoelasticity	Lecture notes

Learning Assessment

Learning Assessment Procedures

Presentation of a group project related to an assembly with the dimensioning of the mechanical components.

Oral exam - Elements to be evaluated: relevance of the answers, quality of their contents, ability to connect with other topics within the program, ability to report examples, quality of technical language, and overall expressive ability.

To guarantee equal opportunities and in compliance with current laws, students can request a meeting in order to plan any compensatory and/or dispensatory measure, according to the educational goals and specific needs. In this case, it is advisable to contact the CInAP (Centre for Active and Participated Integration - Services for Disabilities and/or SLD) professor of the Department where the Degree Course is included.

Examples of frequently asked questions and / or exercises

Project of gears systems and mechanical components.

Shafts design under torque and bending moment.

Mechanical components design: springs, joints, frictions, brakes.

Forced connections.

Fatigue of the materials.

Degree Course in

Mechanical Engineering