What are the principals of compressed air system design?

Answer 1

Compressed Air is used: 

• To produce linear motion for tools, such as hand tools, air hammers, rock drills, vibrators, and power tools.
• For instrumentation, in automatic control systems, modulation of valves, machines, and processes.
• For light industrial and commercial applications. 

A.    Type of Air Compressors:

• Reciprocating Compressor
• Sliding Vane Compressor
• Liquid Ring Compressor
• Straight Lobe Compressor
• Rotary Screw Compressor
• Centrifugal Compressor

B.    Air Compressor Accessories:

• Silencer, for reducing the noise at the suction side of the compressor.
• After-coolers, for reducing the compressed air temperature to the point which can be safe for the equipment.  
• Filters, for removing the particles and dust from entering air to suction side of compressor. .
• Separators, for removing moisture from compressed air.

C.      Compressed Air Dryers: 

For removing fine moistures from compressed air and produce dry compressed air with   refrigeration system.

• Dryers type based on the method of drying:
  1. High pressurization of the compressed air
  2. Condensation
  3. Absorption
  4. Adsorption
  5. Heat of compression

D.     Compressed Air Receivers

Receivers are used for:

 

1. Storage of air.
2. Equalizations of pressure variations
3. Collection of residual condensate.

       Receiver is installed right after compressor and before air separator and dryer.

E.    Piping System Design

• Determine quantity and location of equipment using compressed air.           
• Determine the pressure and flow rate requirement at each location.
• Select equipment and accessories based on end-use requirement.
• Use the appropriate pipe sizing chart for sizing the piping system.

General design parameters as a guide for calculating the system’s total pressure drop (loss):

1. Equipment drop leg: 2 psi
2. Hose allowance: 2 to 5 psi
3. Quick disconnect coupling: 4 psi
4. Lubricant: 1 to 4 psi
5. Filter: 0.5 to 2 psi

F.     Selecting air compressor based on:

1. Total cfm of all connected air using devices.
2. Maximum required pressure of all air-using devices.
3. The total cfm for future expansion allowances.
4. Allowable pressure drops for entire system.
5. Altitude, temperature
6. Location and space available for air compressor and ancillary equipment.