Neumatica

Clean Compressed Air
The Norgren guide to effective air preparation

The air leaving a compressor is hot, dirty, wet and generally at a higher pressure than the downstream equipment requires. A typical 50 dm3/sec (100 scfm) compressor will push 4 500 litres of water and 8 litres of degraded compressor oil into the system in a year along with considerable amounts of dirt particles. Before thisair can be used it needs to be treated to remove the contaminants, have its pressure reduced to the right level, and in many cases have oil added to lubricate downstream equipment.

Figure 1. Compressed air installation, showing examples of air preparation applications. See details on pages 4 and 5.

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APPLICATIONS 4~5

REMOVING CONTAMINANTS 6 ~ 10

PRESSURE CONTROL 11 ~ 13LUBRICATION 14 ~ 15

PROTECTING SYSTEMS, PERSONNEL AND THE ENVIRONMENT 16 ~ 17

SAFE SYSTEMS 18

NORGREN AIR PREPARATION PRODUCT OVERVIEW 19 ~ 21

GLOSSARY 22

REFERENCE TABLES 23

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Compressed air is often wrongly assumed to be a cheap or even ‘free’ source of power. In fact it can be 10 times as expensive as electricity by the time all generation, transmission, treatment and systemcosts are taken into account. Good air preparation must therefore consider the energy consumption of the system and air treatment equipment. The process of air preparation has been at the core of Norgren’s business for over 70 years. The aim of this booklet is to offer guidance on the correct, economic and safe treatment of compressed air in industrial applications. Here we can only provide a briefsummary of the extensive experience Norgren has as a world leader in FRL technology. For more detailed advice contact your local Norgren Technical Sales Centre, Tel: 0345 662266.

APPLICATIONS
The following section shows several typical systems of a generic type and the equipment normally used for the application. Remember every system should be treated on its merits and broken down into severalelements to ensure optimum installation, running and maintenance costs are achieved. The applications below are typically branches taken off a large works distribution mains and isolating valves are usually placed in front of all branches to permit isolation from the mains to allow for maintenance to take place without recourse to complete plant shut-down. For expert advice on the right equipmentfor your application contact your local Norgren Technical Sales Centre, Tel: 0345 662266.

General Pneumatic Circuits: eg: directional control valves and cylinders, in multi-valve circuits, machine cleaning, air motors and high speed tools. A Micro-Fog lubricator is required for the several varying flow paths to ensure full lubrication. (Figure 2)

Figure 2.

Shut-off valve, filter/reg,Micro-Fog lubricator, soft start/dump, relief valve.

Multiple Simple Applications: eg: OEM machines.

It is often a case that with fairly simple machines, lubricated air is require for valving and pneumatic circuitry and oil-free air for air bearings. To keep costs low two separate lines are unnecessary and a typical arrangement from one air supply only can be arranged as shown. Other elementssuch as pressure switches and check valves may be made available within modular systems. (Figure 3).

Figure 3.

Shut-off valve, filter/regulator, oil removal filter, porting block, Micro-Fog lubricator.

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Breathing Air: eg: face masks and hoods, air agitation. The typical application assumes that air intakes are of a reasonable quality with no C0 or C02 contamination. It may in someinstances be a consideration to remove water vapour. (Figure 4)

Heavy Duty Lubrication: eg: large slow moving cylinders. In such applications large amounts of lubricant are required for effective lubrication. Again a soft start/dump valve is shown but is dependent upon the application. (Figure 6).

Direct Injection Lubrication: eg: conveyor chains. The application does not allow for ‘fog’ type...