Pneumatics in the 21st Century (February 2012)
Ian Morris, director of the British Fluid Power Association, looks at the advantages of pneumatic equipment within a range of industrial sectors, and focuses on some of the more recent innovations that have made pneumatics more compelling than ever as an effective means of producing mechanical motion.
Pneumatics is a fluid power technology that has long been deployed in an array of industrial sectors such as mining, offshore/marine, rail, road transport, construction and even dentistry. Examples of pneumatic equipment include everything from pneumatic actuators, cylinders and motors, tools such as industrial nailguns and drills, pressure regulators, pressure switches and vacuum pumps,air brakes on trains, buses and trucks, not to mention air compressors. This equipment can provide the user with a cost-effective, flexible, reliable and safe means of producing mechanical motion.
With regard to pneumatic actuation, the biggest marketplace for this technology is often referred to as general industrial. This market comprises a very large customer base for lightweight low-cost pneumatic movement actuators that are deployed on everything from factory assembly machines, stamping machines, sorting machines and much more. In terms of vertical market sectors within this industrial space they are very diverse and cover pharmaceutical, food & beverage, printing and packaging and many more sectors besides. Therefore, during a market downturn, because of this level of user diversity means pneumatics isn’t normally as badly affected as some other technology sectors that are more reliant on a narrower band of industry sectors. So, from the supplier’s, contractor’s and distributor’s perspective, it is heartening to know the pneumatics market is therefore comparatively well-protected against the vagaries of market demand.
Maintenance and durability
Business aspects aside, there are also a wealth of advantages for users in choosing pneumatics as their preferred mode of power transfer. Take maintenance, for example. If we compare a linear drive unit based on a pneumatic cylinder with an electric rack and pinion drive; we can see that on a rack and pinion system there are many wearable parts, such as bearings and gears. The pneumatic cylinder, on the other hand, just moves backwards and forwards day in day out, with only minimal levels of friction taking place. Additionally, the lack of complexity regarding most pneumatic parts means the maintenance of components is a simple process when the time comes.
Simplicity and affordability
Pound for Pound, the pneumatics option is very cost-effective to operate on a daily basis too. There is also simplicity of installation to consider. These days, the use of highly reliable and flexible nylon tube makes routing much less of a problem. Fast-fit connectors, as their name suggests, make assembly very quick. Another compelling selling point for pneumatic components is their simplicity of design and very good power-to-weight ratio. Pneumatic components are lightweight and easy and quick to install. The design of modern fittings means pipe installations can be done very quickly and cost-effectively – it’s often a simple case of ‘plug and play’. And because of the affordability of pneumatic equipment such as cylinders and actuators, together with the related nylon tubing etc., holding inventory is not a high-cost proposition.
Safety
Pneumatics as a technology in itself can also be a highly suitable technology in flameproof applications. Take mining, for example; pneumatics poses very little risk of fire and so compliance with such legal requirements as the ATEX Directive and what equipment the Directive deems acceptable in environments with a potentially explosive atmosphere is not much of an issue. It is important to add, however, that, due to the growing number of electronic components often used for control and monitoring, any such system should be checked for compliance before installation and use.
Benefits of electro-pneumatics
The above benefits related to areas such as cost, ease of maintenance and safety naturally remain major selling points for pneumatic equipment for users – and indeed industrial system designers – in a diverse range of markets. However, more recent technical innovations have made pneumatic equipment even more attractive for a host of different industrial applications. Chief among these developments has arguably been the increased use of electronics with pneumatic equipment for purposes such as greater accuracy, control and monitoring. This is commonly referred to as electro-pneumatics.
Many industrial companies now want equipment such as control systems such as CAN Bus, and within the pneumatics systems marketplace a number of manufacturers are incorporating CAN bus within their equipment. Many pneumatics equipment providers produce very effective, reliable can bus connectors on, for example, their valves in order that they can plug and play straight into an electronic control system. With regard to monitoring, these systems also afford the user the benefits associated with remote diagnostics. The reaction speed of an electronic controller is also faster than that achieved before this closer relationship between pneumatics and electronics came about.
Designer friendly
This hybrid methodology of coupling the strongest benefits of pneumatics with the strongest advantages that electronics has to offer makes a lot of sense from every angle; whether in terms of programming flexibility, speed of operation, better control and monitoring, even better safety for the user. In this regard, the hybrid model not only affords attractive benefits for users, it also equips the systems designer with enormous flexibility due to both simplicity of operation and adaptability, together with the overriding affordability of pneumatic equipment.
Flexibility
In the past the pneumatics industry employed a number of rotating and tripping switches that worked much like an alarm clock in the way they controlled the on/off function of the system. Now we have the programmable logic controller (PLC), which means users can program a more complex pattern of events. One of the most impressive aspects of the PLC function is that if users want a piece of equipment to take a little longer to close or longer to open, they simply program it electronically while the action is still performed by the pneumatic cylinder.
Energy efficiency
With pneumatics there are also pronounced energy benefits to consider. In static conditions a pneumatic system (or, indeed, fluid power systems in general) do not use any energy. For example, when users want to hold a pneumatic cylinder in its current position they simply lock off the valves necessary to effect the task and the cylinder stays static.
Suitability
It is true to say that within some environments, electrical alternatives may be more suitable. Within food plants, for example, when putting in a piece of automation electrical actuators would arguably be fitter for the task as they don’t produce any exhaust air. However, conversely, in more heavy industrial environments pneumatics would arguably be more suitable because of pneumatic equipment being generally more robust, simple to operate and easy and cost-effective to maintain.
Summary
Pneumatics is a long-proven technology, which, together with more recent developments such as improved design and its relationship with electronics, offers the designer and end user a range of equipment that is easy to use, highly effective, reliable, flexible, energy efficient and affordable to maintain. Whatever branch of industry you work in, pneumatics certainly has a valuable part to play.
The BFPA at IFPEX 2012
The British Fluid Power Association (BFPA) will be exhibiting at the International Fluid Power Association (IFPEX) from 17 to 19 April 2012. IFPEX (The international Fluid Power Exhibition) is the only exhibition in the UK totally focused on hydraulics and pneumatics. On the BFPA stand, staff will be on hand to provide advice and guidance on a wide variety of fluid power issues and themes concerning pneumatic and hydraulic best practice. Visit the BFPA on stand I536 to discuss all your fluid power needs.
Events
-
The Aftermarket Event
02 October, 2024, 9:30 - 03 October, 2024, 15:30
Farnborough International West Entrance, Gate F -
NFPC Annual Industry Exhibition
23 October, 2024, 9:30 - 16:00
Turner Road, Worksop, Nottinghamshire, S81 7AE -
AEMT Awards
21 November, 2024
Double Tree by Hilton Hotel, Coventry -
SMART Manufacturing & Engineering Week
04 - 05 June, 2025
NEC, Birmingham UK