Protecting against safety hazards will protect your operators from injury and reduce risk to your business.
Today, factories can follow several steps to ensure the safety of their employees. These include:
- Performing a risk assessment to determine where safety measures are required.
- Designing automated equipment to eliminate risk and to include safety shields.
- Incorporating additional high-tech solutions to further reduce the possibility of error.
At Eagle Technologies, our experience with factory automation makes us keenly aware of the need to incorporate process safety into our assemblies. We know that our customers depend on us to create equipment that will be safe for their employees to use. Our design system is rigorous, including many of the same strategies we employ to assist quality control. We have even expanded our process safety standards to include newer technologies, which can provide additional support to mechanical fail safes.
Here is a selection of the process safety measures we have implemented for our customers.
1. Light curtains.
A light curtain is a protective field that uses photoelectric sensors to detect when an object breaks the transmission zone. The array of light beams can be arranged in any direction and with any spacing, depending on the application. When the sensor is tripped, a shutdown sequence would halt any production in the area.
Light curtains are very effective for sensing when an object intrudes upon the work area, but they are less effective if part of the assembly process must pass through the light curtain, or if operators must be able to work in the area while the automation process is in motion.
However, recently, I was working with one of our project managers on a project that integrated AGV’s that navigate through an assembly process. Our engineers used dual light curtains and a muting sensor to keep the operator safe and still allow for AGV carts to pass through without disrupting the automated process.
2. Area scanners.
Area scanners are similar to light curtains in that they use radar technology to detect objects within their field. Whenever an operator or another moving machine crosses the perimeter of the area, the machine will cease operation.
Area scanners are useful when factory workers need to work within the vicinity of a machine without getting too close. Area scanners can also be mounted on top of robots to prevent collisions within a factory setting.
Eagle has recently installed area scanners into a multi-station manual assembly line. We integrated AGV’s that carry the customer parts into manual workstations. The area scanners keep the operators safe while the carts are moving throughout the work area.
3. Safety mats.
Pressure-sensitive safety mats can be used to trigger a shut-down sequence when an operator steps on them. They can be wired together to cover a large floor surface, and include redundant circuits so that they will remain active even if a portion of the wiring fails. Safety mats are built to withstand heavy usage so that they will keep functioning after receiving some wear and tear.
Like light curtains, safety mats work well in situations when an entire area must be turned off when an operator is present. However, they are especially effective in situations where mist, dust, or smoke might otherwise affect the operability of a light curtain.
4. Robot interlock switches.
Of course, if a company must keep workers out of contact with a robot, they can always keep an area gated. Robot interlock switches are then used to prevent an operator from entering the gated space before the robot has safely come to a stop.
Robot interlock switches are particularly useful if a robot cannot (or should not) be interrupted during the middle of an assembly cycle. Unlike the previous shut-offs, which are designed to happen instantly because they indicate the presence of a worker, interlock switches are used in situations where a worker is not in immediate danger. By having operators request-to-enter access, to the robot workspace—instead of just walking in—robots have time to finish the automatic cycle without compromising operator safety.
5. Safety PLCs
A safety programmable logic controller (PLC) is an automation controller that has safety features coded into its operating system. It is designed so that, should the PLC fail, it can control the failure in such a way as to cause minimal harm to its environment—and the people who may be within it.
Safety PLCs are designed to interface with emergency stops, allowing them greater flexibility in responding to the conditions of that emergency stop. For instance, a safety PLC could initiate one response protocol if its emergency stop was triggered by an operator passing within its area scanner, and another if an employee engaged the interlock switch.
6. Safety software
Finally, keeping track of various safety measures and their effectiveness can be a major undertaking in itself. It’s easy for manufacturers to be lulled into a false sense of security, and to believe that they have achieved their safety objectives when unmitigated threats still exist.
Safety management software helps organizations track their policies, plans, and procedures for assessing safety risks. It provides the systematic framework for businesses to ensure they have done their due diligence when it comes to the safety of their operators.
Industry 4.0 will bring new innovations to process safety—and we’re here to implement them.
Process safety continues to grow more sophisticated as the technology supporting it improves. The latest generation of Industry 4.0 technology offers new assembly methods and new ways to protect operators.
For instance, personal wearable devices could be incorporated into IIoT systems to help floor managers keep track of where operators are stationed at any given time. Big data can give insights into machine performance to prevent a dangerous malfunction, and AR-equipped devices can help operators see and avoid dangerous operating zones.
Manufacturers understand how poor training, distraction, fatigue, and carelessness can all contribute to quality failures. But each of these factors can also lead to operator injury—or damage to factory equipment. It’s the responsibility of every manufacturer to ensure they are working with automation experts who understand these risks, and know-how to account for them in the design of their automated assemblies using all the technology at their disposal.
At Eagle, operator safety is one of our primary concerns. Our experience in this field is extensive, and we are willing to go to any lengths to meet your safety standards. Contact us today to learn more about what we can do for you.
Brandon Fuller | b.fuller@EagleTechnologies.com
Eagle Technologies, headquarters in Bridgman, MI