Air generation & distribution

1. Air generation & distribution Pneumatics – Module 2

2. objectives • Identify the main parts of a pneumatic system. • Identify the main components of the pneumatic work station TP 101. • List the main parts in the compressed air preparation stage. • Identify the symbol of air compressor and its function. • Identify the symbol of air tank and its function. • Explain the purpose of using the cooling and drying unit. • Identify the main parts of the air service unit. • Identify the symbol of air filter and its function. • Identify the symbol of air pressure regulator and its function. • Identify the symbol of lubricator and its function. • Identify some important pneumatic accessories.

3. introduction • The main function of the air generation and distribution is to provide the system with compressed air which is dry, clean, and at the required pressure. • Air is compressed by the air compressor and delivered to an air distribution system in the factory. To ensure that the quality of the air is acceptable, air service unit is utilized to prepare the air before being supplied to the control system. • Malfunctions can be considerably reduced in the system if the compressed air is correctly prepared.

4. Main parts in the compressed air preparation

5. 1. AIR COMPRESSOR • The Air compressor is used to produce the compressed air for the system by the required volume and pressure. • The maximum operating pressure should be 800-1000 kPa (8 - 10 bar) but in practice it is recommended to operate at between 500-600 kPa (5 and 6 bar) for economic and safe use. • Due to the pressure losses in the distribution system, the compressor should provide pressure between 650-700 kPa (6.5 and 7) bar.

6. 2. AIR TANK (RESERVOIR) • * An air reservoir should be fitted to: • 1. Store and stabilize the compressed air. • 2. Compensate the pressure fluctuation. • 3. Cool the air.

7. 3. AIR FILTER • Compressed air filter has the job of removing all contaminants from the compressed air flowing through it as well as water which has already condensed. • The compressed air enters the filter bowl through guide slots. Liquid particles and larger particles of dirt are separated centrifugally collecting in the lower part of the filter bowl. The collected condensate must be drained before the level exceeds the maximum condensate mark, as it will otherwise be re-entrained in the air stream.

8. 4. COOLING & DRYING UNIT • As the air comes out from the compressor very hot and humid; The cooling and drying unit is used to: • 1. Condensate the water vapor (humidity) from the compressed air. • 2. Reduce the compressed air temperature. (cooling) • The accumulation of condensate depends largely on the relative air humidity. The relative air humidity is dependent on the air temperature and the weather situation. • To remove the humidity, we use many types of air dryers, the very common and practical one is by using a cooling unit which cools the air and at the same time removes the water vapor.

9. 5. SHUT OFF VALVE It is used to open and close the compressed air supply manually.

10. 6. PIPING The pipe diameter of the air distribution system should be selected in such a way that the pressure loss from the pressurized reservoir to the consuming device ideally does not exceed approximate 10 kPa (0.1 bar). Piping Layout Selection Factors of the Pipe Diameter

11. SELECTION FACTORS OF THE PIPE DIAMETER • 1. Flow rate • 2. Line length • 3. Permissible pressure loss • 4. Operating pressure • 5. Number of flow control points in the line

12. PIPING LAYOUT The air comes from the compressor to the compressed air supply outlets through a piping system. PIPE – RUN DISTRIBUTION SYSTEM The pipe lines are installed in the direction of flow with a gradient of 1 to 2% repair. This is particularly important in the case of branch lines. Drainage is used to remove the condensed water from the lines at the Lowest point. Shut-off valves are used to block sections of compressed air lines at any stage for maintenance.

13. 7. AIR SERVICE UNIT • The air service unit is a combination of the following: • 1. Compressed air filter (with water separator) • 2. Compressed air regulator • 3. Compressed air lubricator • The main function of the service unit is to provide the pneumatic system with a well cleaned, lubricated and regulated compressed air. (Condition the compressed air).

14. 8. PRESSURE REGULATOR (Reduce/regulate the pressure). The purpose of the regulator is to keep the operating pressure of the system (secondary pressure) virtually constant regardless of fluctuations in the line pressure (primary pressure) and the air consumption.

15. 9. AIR LUBRICATOR • (Lubricate the moving parts) • Most moving parts require some type of lubrication. • Pneumatic components can be lubricated by using an air line lubricator ,a device for adding lubricating oil in aerosol form into a compressed air line. The air passing through the lubricator transports the lubricant to air tools, cylinders or other air operated equipment.

16. 10.MAINFOLD (DISTRIBUTOR) • It is used to provide multi equal pressure outlets. • Each output port has A check valve (Non return valve). T- junction Pressure Source

17. 11.TUBES & FITTINGS • Shown below are some types of tubes that are used in connecting pneumatic circuits. • Shown below are some important fittings such as T connections and cross connections.

18. 12. PRESSURE GAUGE It used to display the actual amount of the pressure in two main units PSI and bar. 1 bar= 14.7 PSI

19. CLASS ACTIVITY • Solve the worksheet found at the end of the module

20. FOR FURTHER READING: • www.Fest-didactic.com • http://www.eng2all.com/vb/t28932.html • http://www.logiclab.hu/lesson.php?fe=2

21. Don’t forget to submit h.w.2