Compendium online: www.drucklufttechnik.de compendium compressed air compendium compressed air compressed Otto-Boge-Str. 1-7 D-33739 Bielefeld [email protected] www.boge.com Revised 6th edition 2004 The existing publication has been carefully developped. However, author and publisher do not assume liability for the correctness of statements, notes and advice as well not for eventual errata. All rights reserved. Reproduction, including that of excerpts, is forbidden. No part of this publication may be reproduced in any way (photocopy, microfilm or any other medium) or be used, copied or distributed on electronic systems, educational purposes included, without the prior written consent of the publisher. © 2004. All rights reserved by BOGE. Published by BOGE, Otto-Boge-Str. 1-7, D-33739 Bielefeld Author of editions 1-5: Ulrich Bierbaum (BOGE) 6th edition revised by Jürgen Hütter (BOGE) Printed on 80 g woodfree paper with mineralfree colours Distribution: Hoppenstedt Bonnier Zeitschriften GmbH, D-64295 Darmstadt Print: Druckhaus Darmstadt GmbH, D-64295 Darmstadt Printed in Germany ISBN: 3-935772-12-2 Table of contents Contents Chapter Page Part 1 1.1 The history of compressed air ...............................................1 Fundamentals of 1.1.1 The origin of compressed air ................................................1 compressed air 1.1.2 The first applications of compressed air ...............................2 1.2 Units and formula symbols ....................................................6 1.2.1 Basic units ............................................................................6 1.2.2 Compressed air units ...........................................................6 1.3 What is compressed air ? .......................................................7 1.3.1 The composition of air ..........................................................7 1.3.2 The properties of compressed air ........................................7 1.3.3 How does compressed air behave? .....................................7 1.4 Physical fundamentals ...........................................................8 1.4.1 Temperature .........................................................................9 1.4.2 Volume .................................................................................9 1.4.3 Pressure .............................................................................10 1.4.4 Volume flow ........................................................................11 1.5 Compressed air in motion ....................................................13 1.5.1 Flow behaviour ...................................................................13 1.5.2 Types of flow ......................................................................13 Part 2 2.1 The advantages of compressed air .....................................14 Applications for 2.2 Pressure ranges ....................................................................17 pneumatics 2.3 Possible applications for compressed air ...........................18 2.3.1 Tensioning and clamping with compressed air ...................18 2.3.2 Conveyance by compressed air .........................................18 2.3.3 Pneumatic drive systems ...................................................19 2.3.4 Spraying with compressed air ............................................19 2.3.5 Blowing and flushing with compressed air..........................19 2.3.6 Testing and inspection with compressed air .......................20 2.3.7 Using compressed air for process control ..........................20 2.4 Examples of specialised applications .................................21 Part 3 3.1 Compressors (compactors)..................................................24 Compressed air 3.1.1 Dynamic compressors ( Turbo-compressors ) ....................24 generators 3.1.2 Displacement compressors ................................................24 3.2 Types of compressor ............................................................25 3.2.1 Standard compressors .......................................................26 3.2.2 Piston (reciprocating) compressor......................................27 3.2.3 Diaphragm compressor ......................................................29 3.2.4 Free piston compressor ......................................................30 3.2.5 Rotary vane compressor ....................................................31 3.2.6 Liquid ring compressor .......................................................32 3.2.7 Screw compressor .............................................................33 3.2.8 Roots compressor ..............................................................34 3.2.9 Axial compressor................................................................35 3.2.10 Radial compressor .............................................................36 I Table of contents Chapter Page 3.3 Piston compressors ..............................................................37 3.3.1 General ..............................................................................37 3.3.2 Suction capacity - output ....................................................38 3.3.3 Cooling ...............................................................................39 3.3.4 Coolant ...............................................................................40 3.3.5 Control of reciprocating piston compressors ......................40 3.3.6 Advantages of reciprocating piston compressors ...............40 3.3.7 Components of a piston compressor..................................41 3.4 Screw compressors ..............................................................42 3.4.1 General ..............................................................................42 3.4.2 Compression process ........................................................42 3.4.3 Method of operation ...........................................................43 3.4.4 Oil circuit ............................................................................44 3.4.5 Pneumatic circuit ................................................................45 3.4.6 Heat reclamation ................................................................46 3.4.7 Intake control......................................................................46 3.4.8 Advantages of screw compressors.....................................46 3.4.9 Main components of a screw compressor ..........................47 3.5 Components ..........................................................................48 3.5.1 Drive motor.........................................................................48 3.5.2 Drive belts ..........................................................................48 3.5.3 Belt tensioning....................................................................48 3.5.4 Inlet and pressure valves ...................................................49 3.5.5 Safety valve ........................................................................49 3.5.6 Intake filter..........................................................................49 3.6 Compressor lubricants and coolants ..................................50 Part 4 4.1 Pressure definitions ..............................................................51 Control of compressors 4.2 Operating status ....................................................................52 4.2.1 Stopped ( L0 ) .....................................................................52 4.2.2 Idle ( L1 ) .............................................................................52 4.2.3 Part-load ............................................................................53 4.2.4 Operating load ( L2 ) ..........................................................53 4.3 Controlling individual compressors ....................................54 4.3.1 Intermittent control .............................................................54 4.3.2 Idle mode control................................................................54 4.3.3 Delayed intermittent control................................................55 4.3.4 Part-load control .................................................................56 4.3.4.1 Proportional regulation .......................................................56 4.3.4.2 Frequency control...............................................................57 4.4. The ARS control concept .....................................................59 4.4.1 Autotronic ...........................................................................60 4.4.2 Ratiotronic ..........................................................................60 4.4.3 Supertronic.........................................................................61 II Table of contents Chapter Page 4.5 Control of several compressors ..........................................62 4.5.1 MCS 1 and MCS 2 .............................................................62 4.5.2 MCS 3 ................................................................................63 4.5.3 MCS 4 ................................................................................64 4.5.4 MCS 5 ................................................................................65 4.5.5 MCS 6 ................................................................................66 4.5.6 MCS 7 ................................................................................67 Part 5 5.1 Why treatment ? ....................................................................68 Compressed air treatment 5.1.2 Planning information ..........................................................69