June 2021

PWE 40th Anniversary June 2021 www.pwemag.co.uk Plant & Works Engineering | 13 line and assess what modifications should be made. As well as reducing injuries in factory operatives, the biomechanics lab helps SEAT save time and money by determining the design of assembly lines before they are built. “Some workers perform the same motions up to 100 times a day, so job rotation and the design of the assembly line are crucial in order to prevent possible injuries,” said Sonia Garcia, who is responsible for Ergonomics at SEAT. “The avatar is a 3D image that accurately reproduces the speed and range of the motions. We can simulate different positions until we find the best option, for example, for attaching the rear hatch. This allows us to save time and money in comparison to performing tests on the actual line.” Systems integration Early automated manufacturing systems tended to use proprietary assemblies based on the products of a single supplier of automation equipment. One supplier’s equipment did not easily talk to anyone else’s. But with the emergence of common protocols, such as Ethernet/IP and Profibus, it is increasingly possible to use best-in-class products from a variety of suppliers. These can now be interconnected in a relative straightforward way, known as “plug-and-play”. Display technology An average person stares at displays around five to six hours a day, about half the time we are awake. Display technology plays an important role in factories, as in everyday life. In 1981, CRT displays were commonplace in offices, with so-called ruggedised versions for the plant floor. The invention of LCD and plasma screens occurred in the 1960s. LCD technology makes flat-screen television possible. In 1995, full colour plasma displays were introduced, but have lost nearly all market share, mostly due to competition from the low-cost and low power consumption of LCD and the more expensive but high-contrast OLED flat-panel displays. An OLED (organic light-emitting diode) is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound that emits light in response to an electric current. Digitisation and maintenance Over four decades there has been a progressive move from reactive maintenance - having spare parts available for when a part fails - to preventive and then predictive maintenance. Digitalisation is helping manufacturers take advantage of big data analytics to bundle and sell a variety of services to their customers. For example, manufacturers of machinery can offer conditioning-based maintenance that includes real-time monitoring of the equipment. In addition to bringing in additional revenues, this also helps to foster a stronger long-term relationship that can increase customer retention. Preventive maintenance (PM) is work that is scheduled based on calendar time or asset runtime. This reduces plant downtime compared to reactive maintenance. PM can be compared to an annual physical check-up. Technicians perform these maintenance tasks when everything is still running smoothly in order to prevent future unplanned breakdowns. Predictive maintenance (PdM) is work that is scheduled as-needed based on the real-time conditions of assets. Modern assets, as well as upgraded legacy assets, can use internet communications to relay information about their condition and likely time to failure. This approach promises cost savings over routine or time-based preventive maintenance, because tasks are performed only when warranted. Plant downtime is reduced still further. Safety over WiFi DFA Media recently ran a webinar sponsored by Euchner in which the subject of running plant safely using WiFi was discussed in depth. One reader with extensive experience in implementing safety over WiFi commented that it should not be considered if you are only trying to save wiring costs. 5GHz has become the new go-to waveband for virtually all new WiFi-enabled devices entering the factory or office environment. The UK has a limited number of sub-frequencies which we are allowed to use. Devices that come in from the EU can have been set up and tested using sub- frequencies which are not allowed in the UK, and without the correct knowledge, the end user does not know. And despite the use of ProfiSafe (the well- known and stable safety protocol), the use of leaky coax cables for signal transmission can make a network susceptible to external and internal interference! So a promising technology, but still a work in progress. Onshoring Offshoring describes a situation where work that was once performed in-house is shipped to third-party entities (often located overseas) who can perform the task at a lower cost. Driven by inferior or inconsistent quality, shipping delays and communication challenges, many manufacturers are reversing this trend and bringing back to work to local subcontractors, or even bringing it back in-house (onshoring). Apart from being good news for local suppliers, as we urgently face the challenge of climate change, it must be sensible for the carbon footprint for manufacturers to focus on their local markets and proximate supply chains, rather than committing to trading over huge transportation distances. Of course, climate change was not at the top of the agenda in 1981, although perhaps it should have been! In another 40 years, we will know if we addressed the problem in time. An old personal computer with CRT monitor An operator on the control panel of old power plant