How to design integrated safety into machines from the start?
Udgivet kl. 19. september 2019 i Sustainable Manufacturing
Safety is a vital element of any modern production or packaging line. Safety systems protect employees and prevent malfunctions from causing damage to valuable products and equipment. If there’s an issue, a good safety system will stop the line to avoid any potential accidents, which also allows the line to be restarted quickly.
In the past, safety was often an afterthought for both individual machines and the whole production line. Each piece of equipment was designed to perform a specific task and any safety measures were often added afterwards as a separate system. This was also true for production lines.
The benefits of integrated safety
Today, safety is designed into both individual machines and the production line from the start. This integrated safety ensures that every aspect of a machine’s operation is accounted for and is captured in the data used by the control system.
Machines designed with integrated safety deliver maximum safety and security. If a problem occurs, they provide all of the data needed to evaluate the issue and to ensure that it won’t occur again. Without this data, there’s no quick way to identify the problem if a production line stops – and tracking it down can be costly in both time and production.
This is avoided in a production line composed of integrated machines. Each component and activity in the line is closely monitored in real time by control software. Omron’s Sysmac is an example of a control system that brings together all of the intelligent, integrated and interactive elements. This allows any actual or potential problems to be identified at early stage so that actions can be taken to mitigate the issue.
For instance, these actions could modify production to compensate for an isolated issue so that the operation doesn’t have to be completely shut down. Even if the line has to be stopped, the system can decide whether the machine or line can remain in a standby condition rather than suffering a complete or emergency stop. This means that data can continue to flow so that the controller or operator knows what’s happening and can maintain an optimum performance even during times of operational disruption.
This approach is also safer and more efficient for maintenance personnel. They will have all the information they need on any issues even before going to the line and can therefore be prepared to fix them. They will know which tools might be needed and the safety precautions to take. Furthermore, the line’s safety functions will continue to protect them if an issue arises during the maintenance.
Integrated v non-integrated safety
In a non-integrated system, a basic programmable logic controller monitors and executes motion and a separate on/off safety relay safeguards the operation. For accurate maintenance scheduling, operators have to keep a reliable and accurate log of incidents and operations. In older systems, this might be just a handwritten journal – so the information won’t be available digitally. This is a poor way of monitoring a machine’s condition to ensure a safe operation and to schedule predictive maintenance.
An integrated system is much more sophisticated: all signals and inputs are merged within an intelligent controller, which replaces discrete safety relays with advanced logic. This removes the uncertainty caused by manual data records.
With an integrated system, all of the information is automatically recorded locally and can also be made available online. Knowing when to carry out maintenance is a critical factor in reducing the likelihood of parts breaking down, which could directly affect both production and operator safety. By digitally capturing every event (e.g. each time a door is opened and closed), statistics such as the mean time between failures can be checked and preventive maintenance scheduled.
The importance of safety services
Whether you’re building equipment or running production lines, you need to make sure that your equipment and/or line is safe and meets any local or international regulations. That’s why Omron has developed various services that provide safety advice. Our primary aim is to ensure that there are no accidents on production lines, whilst improving production, increasing safety and making the line more flexible.
Typically, these services start with an assessment of safeguards that gives a diagnostic validation of equipment, highlighting areas that can be improved. Whilst small improvements can often be handled by the manufacturer’s technicians, more significant improvements might require the design and implementation of a customised solution, along with additional training on new features by experts.
The validation and assessment of safeguards can also ensure that the machines and systems meet local equipment regulations. Safety services, whether provided by us or by someone else, will ensure that your production line meets all the relevant safety requirements and regulations so that you can then focus on meeting your production targets.