Almost all automation processes are potentially dangerous. So the key to creating a safe working environment for operators – and anyone else who comes into contact with a process – is to be aware of the potential dangers, and to take all feasible steps to eliminate, protect against, or provide warnings about them. Even when the danger comes from the most unexpected sources.
Compressed air is one of the most versatile and safe media for use in automation processes. Used correctly it’s efficient, adaptable, economical and clean. Like most other media in this context, it’s also generally safe – unless, that is, it’s used or handled incorrectly.
IMI Precision Engineering have been manufacturers of pneumatic systems since the earliest days of machine automation. So they have the knowledge, experience and solutions to ensure that compressed air is an effective answer in automation processes, and a safe one.
In addition, the company has more than half a century of experience in creating specific product solutions for use in safety applications, to help keep compressed air as safe as it’s indispensable.
An automation process machine or system doesn’t have to be complex to make it potentially hazardous. So when safety is under consideration, it’s important not to overlook even the simplest installations and applications.
For example, the failure of even a simple flexible hose installation could create a safety risk. So it’s worth fitting anti-flay devices. In the same situation, incorporating system pressure limiters can have a double benefit: not only helping with safety, but also keeping pressure limited to its optimum, which helps to maintain energy efficiency.
But whether or not the system is simple, many safety solutions can be.
Air exhausting from a system often results in noise which – if it’s loud, or continuous – can at best make working conditions uncomfortable for the operator, and at worst actually be a health risk. It can also create a “mask” of background noise which hides other sounds, causing safety problems for operators.
A simple solution is the installation of efficient exhaust port silencers, such as the IMI Norgren range of Quietaire heavy duty units. Available with male or female threads, they can easily be connected to most pneumatic devices, to reduce the noise without affecting system performance.
Local and global legislation – such as the European DIN EN ISO13849 – sets many safety requirements which must be met by machine designers and machine users: from safety valves with self-monitoring functions, to machine validation and relevant documentation.
It’s also important for an operator to know that when an emergency situation does arise, the machine elements are at least under controlled conditions. This means that the emergency situation can be investigated and corrected safely, before re-starting the equipment.
To establish the controlled conditions, there are two key issues.
Firstly, the air supply must be quickly and effectively evacuated. And secondly, maintenance operatives must be kept safe during remedial work.
To evacuate the air from a complex machine system to make it safe during an emergency, a dual cross monitored dump valve is essential. This will “dump” – or exhaust – downstream air in the shortest possible time. IMI Norgren offers two versions, including one with an integrated variable soft start function, for equipment which requires a controlled re-start of the air supply. Pneumatic monitoring of the valves ensure they meet all the requirements of current safety legislation, without the need for additional electronics.
Ensuring the safety of maintenance operatives requires maintenance and repair to be carried out under “LOTO” (lock out tag out), conditions, which means dangerous machines are properly shut off and can’t be accidentally re-started.
Pressure to be Safe
Even simple blow guns – as used throughout industry – are affected by health and safety guidelines, which specify a maximum air pressure of 2 bar. The most effective way to comply is to have the pressure pre-set and have the device secured so it cannot be adjusted by the operator.
IMI Norgren offers a pre-set tamper-proof regulator from their R16 range. The unit is factory set to the required pressure, and locked prior to despatch. For an additional level of safety in applications using flexible hoses, the unit should be used in conjunction with an air fuse.
With the correct equipment correctly installed, used in the correct way for the application it’s designed for, automation process equipment presents no more risk than most industrial equipment. Compressed air is no exception. However, as with all such equipment, it is essential that operators are fully trained in its use, and if personal protection equipment is required, it must be provided and it must be worn.
Follow these basic rules, and compressed air can continue to be an integral, valued, versatile and safe element of your automation processes. You can’t see it, but you can’t see yourself working without it.