From article originally published in ERJ's January/February issue:
Factory safety is an issue that encompasses all levels of a manufacturing organisation, from the plant shopfloor to the boardroom as well as companies throughout the supply chain serving its facilities.
This is a point well understood by those charged with ensuring the highest standards of health & safety in the tire and rubber manufacturing industries.
“These machines won’t differentiate between a human and a tire and that can make for a dangerous working environment,” he commented.
“We transport a combination of raw materials, semi-finished and finished products through our plants, each with their own complexities and dangers. We also use harmful chemicals in the production of our tires. It’s therefore a place where safety has to be paramount.”
To maintain the highest safety levels at its plants, SRI is continuously looking at improving safety standards by reducing human involvement in areas where accidents can occur. The company also offers on-going safety training to operators and encourages them to suggest improvements.
Asked to identify a successful safety initiative at SRI, Leendertse pointed to the recent automation in the production of the company’s Falken brand. This involved processes for adding ingredients, thereby “decreasing the operators’ contact with the raw materials.
“We have also automated and covered the transportation of semi-finished and finished product so that the operator’s working space remains free. Automated fencing surrounding the machine during processing makes it impossible for the operator to enter the area whilst cutting, pressing or mixing is in progress. We have also enhanced lighting to improve working conditions.”
Going forward, SRI/Falken is looking to improve conditions even further by automating the transportation of components around the manufacturing equipment away from the operator and by making the equipment more visible.
Worker feedback is the focus of another initiative SRI with a scheme called Safety First, in which the operators are incentivised to identify and report possible risks, making their own workplace safer.
“The role of our operators has changed over the years,” concluded Leendertse. “In the past, operators were required to enter all machine-operated areas; they were very hands-on. Today they are there to assist the machines in operating as required.”
For its part, Trelleborg has significantly improved its safety performance over the last 10 years, under its Safety@Work safety management system, which establishes a common standard for all manufacturing entities worldwide.
“The first step is to create awareness about Safety@Work at each level of the organisation,” explains Marco D’Angelo, industrial director at Trelleborg Wheel Systems and responsible for the Tivoli tire facility near Rome, Italy – one of the largest manufacturing facilities within the Trelleborg group.
Safety should not only to be discussed when there is an injury; it’s crucial to include safety in every process, from product design to delivery, D’Angelo emphasises.
“It’s a cultural change, requiring time, a huge effort, commitment and coherence by the whole of the facility’s management,” he said. “There should be no negotiations or compromises on safety. This approach helped the Tivoli manufacturing facility to reduce injuries by 90 percent over the past 10 years."
At Tivoli, safety involves everyone, including operators and trade unions in cross-functional teams that are pro-active in risk analysis and proposing solutions. Also, continuous improvement efforts focus on near misses and safety suggestions coming from operators.
D’Angelo went on to note that the process complexity and equipment design requirements of the rubber industry mean that there remains “residual manual operation” with related risk.
Trelleborg plans to reduce these risks by introducing anthropomorphic robots designed and tailored to each process.
When robots cannot be used, D’Angelo said risk levels can be reduced by ‘clever barriers’ – optical devices that can create different safety areas for different operations on the same machine.
For her part, Sara D’Offizi, health & safety manager at Trelleborg, notes that over the last few years, tire dimensions have increased and semi-finished products have, therefore, become more critical to handle.
“Machine manufacturers should find solutions to support this trend,” said D’Offizi, who believes that new ideas to reduce manual handling and increase safety in mechanical handling could be the answer to some of the issues faced in rubber production.
It is also, she added, important to work on the process of building tires to find new technologies to achieve this in a safer way.
Indeed, in a recent safety initiative, Trelleborg created an inter-functional team to review the operational sequence of building tires. The machine cycle was divided into elementary steps and analysed with a group of operators.
Based on this review, the approach to operations was changed to reduce machine-operator interaction eliminating some manual actions. This reduced risks and a new work standard was established.
And as D’Angelo concluded: “The rubber manufacturing sector has a couple of processes that are critical from a safety perspective, such as open mills and calendering, where it’s not possible to apply the European Machine Directive.
The residual risk for this equipment, he added, “remains a critical point. This is an area where equipment suppliers and manufacturers could work together to find new solutions to eliminate risks of serious injuries.”
At machinery maker VMI, Jan Grashuis notes a real trend towards giving worker safety a much higher priority in almost every country, and the elimination of many activities seen as acceptable 10 years ago.
“In the EU and North America the key factor is regulation, but we also see changes in south Asia, where regulations are less robust,” said Grashuis.
Another important driver is the desire of ambitious companies to partner with global OEMs.
“To be a strategic supplier to a major automotive company, you have to reach the highest standards for safety as well as for everything else,” said the VMI executive.
“VMI sees standards being levelled up,” he continued. “We comply with the highest safety standards in the world as an EU manufacturer and we apply the same standards everywhere we operate.”
Tire makers and their machine suppliers, however, need to strike the right balance between safety, productivity, efficiency and machine ergonomics.
“Difficulties arise when you reverse-engineer safety features into an existing machine,” said Grashuis. “This does not work well and can give operators an incentive to break the rules to keep productivity high.”
The way forward, he said, lies in adaptive safety systems that enable operators to interact with the machine without stopping it or jeopardising their safety: “The technical changes now driving improved safety standards are almost all coming from systems enabled by sensors that adjust machine operation to the position and actions of the operator.”
For VMI, so, a key challenge is to design equipment with fully-integrated safety systems that help the operator to do their job better, while also keeping them safe. This means eliminating any perceived conflicts between productivity and safety so the operator has no reason to by-pass the system.
Looking forward, Grashuis sees control technology, and the flexibility that it allows, as offering the most potential for improving the safety of tire/rubber manufacturing.
He points, for example, to VMI’s ActiZones which uses PLCs to enable the machine to run at a safe speed, while disabling potentially dangerous moves as the operator gets closer.
“The machine adapts to the person, not vice versa,” comments the VMI expert.
Likewise, he said, hands-off technology makes it unnecessary for the operator to get close to moving parts: “By automating processes, operator interaction with the machine is cut to a minimum. This has a huge impact on safety, as it keeps the operator away from moving parts.”
Grashuis concluded: “Tire and rubber industries are moving towards a smart-factory or Industry 4.0 approach, with an emphasis on interconnected cyber-physical systems. This will reduce the role of people in manufacturing, while extending the use of intelligent machines programmed to avoid accidents.”