Lecturer: Paolo Beduschi  

Course name: Misure e strumentazioni industriali
Course code: 062200
Degree course: Ingegneria Elettrica
Disciplinary field of science: ING-IND/12
The course relates to:
University credits: CFU 5
Course website: n.d.

Specific course objectives

The course describes some typical devices used in the industrial process control: physical quantity gauges, signal transducers and transmitters, control valves and actuators, automatic control loops, etc.; the course is focused on operation and maintenance of industrial plants and includes a visit to a thermal power plant.

Course programme

The lecturer will explain and discuss the subject below

Introduction
Outline of automatic control improvements in the industrial processes and present trends for the instrumentation. Sensors and signal generation; errors of sensors and transducers; analog / digital output; examples of control loops; signal transmission (cables, field bus, optical fibre, wireless, pneumatic, etc.); standard ranges; protection against environmental interferences.

The industrial context
The industrial context: classification of hazardous areas and apparatus requirements for use in explosive gas atmospheres or in the presence of combustible dusts; protection against lighting.

Temperature measurement
Thermometers, thermocouples, resistance thermometers, thermistors: characteristics and performances, precision, selection criteria, typical installations and uses; calibration of thermometric devices; Radiation thermometers and temperature gauges without contact.

Pressure measurement
Typical pressure gauges: glass tube with liquid column; Bourdon tube, capsule, diaphragm, solid state cells. Differential pressure gauges: mode of installation and accessories. Pressure gauges calibration

Level measurement
Direct and indirect level measurement devices: reflex / transparent level gauges; floats and displacers; differential cells; bubblers; torsion bar; resistive, magnetic, capacitive, inductive, magnetostrictive devices; ultrasonic; radar. Level sensor features: resistive, magnetic, magnetostrictive, capacitive, ultrasonic, radar. Type of level gauges used for liquids, powders, slurries, granular bulks. Calibration of level gauges operating at high pressure and high temperature conditions.

Flow measurement
Bernoulli principle and fluid flow measurements (compressible and uncompressible fluids); water flow in channels and pipes; primary devices for pipes (orifices, Venturi tube, Pitot tube, Coriolis, ultrasonic, thermometric, inductive); flow signal generation (DP cells, square root extractor); flow counters.

Displacement, vibration and noise measurement
Sensors used to detect displacements and speed (linear and rotating motion). Accelerometers used to detect vibrations and typical applications in rotating machinery monitoring. Noise in the industrial plants: noise level monitoring and normal equal-loudness-level contours.

Control valves and actuators
Control valve construction features; glossary. Parameters to be considered for control valve choosing: valve flow characteristic curve and rangeability. Safety valves: function and features. Electric / pneumatic actuators and hydraulic cylinders: typical applications. Control valves and positioners: function and performances.

Analytical instruments
Conductivity, pH and turbidity measurements: construction features; installation criteria to obtain good performances. The chromatography and its evolution in the industrial applications: use of chromatographic devices in combustion control. Instruments to detect powders, CO, SO2, NOx, and O2 at the stack of a great combustion plant: lay-out of sampling system and operation criteria.

Miscellanea
The weighing systems: scales, load cells, continuous weighing conveyors. Description of no destructive tests for mechanical equipments: liquid penetrant examination, eddy currents, ultrasonic tests, radiographies. Description of diagnostic tests for electrical equipments: gas presence in transformer oils, partial discharge in winding insulation, flux test for detecting stator core problems, wedge tightness detector.

Course entry requirements

Elements of electrical technology, chemistry, fluids dynamics, thermodynamics.

Course structure and teaching

Lectures (hours/year in lecture theatre): 40
Practical class (hours/year in lecture theatre): 0
Practicals / Workshops (hours/year in lecture theatre): 0

Suggested reading materials

The lecturer will supply lecture notes concerning the course matters.

Testing and exams

No intermediate testing will take place; a single oral examination will verify learning and knowledge.