A Simple Guide to the Key Parts of a Pneumatic System

PNEUMATICS EXPLAINED

The easiest way to explain pneumatics in the simplest terms is to imagine a compressed air ring main. Within the ring main there are four main components operating the functionality of the system:

• Cylinders
• Valves
• FRLs
• Fittings and Tubing

The cylinder is the external output, the end result or the movement you are setting out to achieve.

The valve is the control element within the system. For example, how fast? How many movements do you require from the cylinder?

FRL’s refer to the preparation of the air. The air must be cleaned, filtered and regulated or maybe even lubricated before it is channelled into the system. To do this we use a filter, regulator lubricator (FRL).

Fittings and tubing are self-explanatory, they are the connections and pipes that connect the system together.

WHERE ARE PNEUMATICS USED?

95% of industries use some form of compressed air using pneumatic components. The most prevalent include:

• Packaging
• Food & Beverage
• Plastics & Rubber
• Fluid Control
• Automotive
• Electronic Systems
• Textile Machinery
• Assembly & Robotics
• Printing & Paper
• Woodworking Machinery

BASIC QUESTIONS TO SPECIFY PNEUMATIC CYLINDERS

1. What is the cylinder’s bore and stroke size?
2. Do you know if it is an ISO (industry standard) cylinder?
3. If so, what is the ISO reference?
4. Is the cylinder double-acting or single-acting?
5. What thread port size is it, i.e. M5, 1/8, 1/4, 3/8 or 1/2”?
6. Are cylinder mounting brackets required? E.g. rod fork end, rear clevis, swivel combination.
7. Are any additional accessories required? E.g. pneumatic fittings, proximity switches or flow controllers.

BASIC QUESTIONS TO SPECIFY PNEUMATIC VALVES

1. How is the valve operated? I.e. solenoid, pilot, mechanical or manually?
2. What is the configuration of the valve or put another way, how many positions does the valve have? For example:

• 3/2 = 3 Ports, 2 Positions
• 5/2 = 5 Ports, 2 Positions
• 5/3 = 5 Ports, 3 Positions

3. Is the valve normally open (NO) or normally closed (NC)?
4. What is the port size of the valve? I.e. M5, 1/8, 1/4, 3/8 or 1/2”?
5. Are any accessories required? For example, coils, pneumatic fittings or tubing? If coils are required, a voltage will also need to be specified.

BASIC AIR PREPARATION QUESTIONS

1. What is required? E.g. A filter? A regulator? A lubricator? Or a filter regulator*? Or a filter, regulator, lubricator (FRL)*? * These are pre-assembled kits.

2. What thread/ port size is required? I.e. 1/8, 1/4, 3/8, 1/2”?
3. What is the required pressure range? (0-15 Bar standard)
4. Are any accessories required? E.g. wall mounting brackets, tamper proof cap, pressure gauge or filter service kit?

BASIC QUESTIONS TO SPECIFY PNEUMATIC FITTINGS

1. Is a specific material required? I.e. brass nickel plated, technopolymer (plastic) or stainless steel?
2. What type of fitting is required? For example:

• Push in fitting
• Push on fitting
• Pipe fittings/ BSP adaptor
• Air brake fitting

3. What sort/ model of fitting is required? E.g. straight, elbow, tee, reducer etc.
4. What thread is required? E.g. M5, 1/8, 1/4, 3/8 or 1/2?
5. What port connection is required? E.g. 4, 6, 8, 10, 12mm?