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Southern Manufacturing & Electronics

Farnborough, Hants(GU14 6XL)

11/02/2020 - 13/02/2020

Southern Manufacturing and Electronics is the most comprehensive annual industrial exhibition in the (more)

Industry 4.0 – Winning by Marginal Gains

The holy grail of the fourth industrial revolution – Industry 4.0 – appeals to our human desire for sea change – a magical something that leapfrogs us right over the competition. The prospect is an enticing one: If only engineers had a magic wand to wave over their processes, it could cut wastage or downtime in half, achieve a step change in consistent product quality, or boost yield and margins.

For most of us, of course, progress is rarely measured in flashes of inspiration, as much as in accumulated beads of perspiration as we build on what’s already achieved. Usually, we don’t have the luxury, the opportunity, or the cash, to engineer the kind of transformation that may come about once in a career.

In the field of sports science, winning through ‘marginal gains’ is a well-established formula, that has propelled elite teams to the top of their game. Famously pioneered by Sir Dave Brailsford, general manager for Team Sky and one-time head coach at British Cycling, it goes like this: Hunting down opportunities to make a 1% improvement across a wide range of parameters can add up to a cumulative effect that helps you beat your competitors decisively.

Experience tells us that staying ahead of the game can mean aggregating many small improvements made to even the most prosaic of equipment and processes. Achieve two percent extra productivity here, four percent there and suddenly you have a worthwhile margin to shout about.

At SICK, we work with customers all over the world in just this way. Sensors and sensing systems are the trusty footsoldiers that cut downtime, increase throughput, improve product consistency and protect employee safety. Counted in multiples of one device, the gains could seem small, but multiply the improvements across a whole line or factory – whether it be in fewer rejects, or reduced stoppages, and the return on investment is significant.

Slices of Success

Let’s take the example of a meat and cheese slicing and packing operation. The ‘headline’ solution, a SICK IVC3D 3D smart camera detects height, volume and shape of a block of cheese or processed meat. Wastage from misshapes, ends of the block or part slices is reduced and the need to add in ‘make-up’ slices to ensure the on-pack weight eliminated.

The profile of a cheese or meat block is variable, so a SICK OD Mini displacement sensor provides accurate measurement data for the 3D slicing operation. W4S3-Inox photoelectric sensors detect when product is placed on the conveying line and at the infeed of the slicer.

As a result of selecting sensors with hygienic mountings and robust resistance to high-temperature washdown and cleaning, downtime and wastage due to unforeseen sensor failure is radically reduced.

Reliable speed detection of the conveyor belt by a SICK DFS60 Inox encoder enables precise location of the product for the slicer to ensure accurate slicing, neither too thick nor thin, all co-ordinated via Ethernet IP-enabled network and IO-Link bi-directional data communication from the sensors.

So, while the SICK IVC3D camera improves margins through precision slicing and improved product utilisation, additional SICK sensors add marginal gains of their own, ensuring that the improvements are not compromised through poor line control and downtime. The cost of the additional sensors may be one tenth of the vision camera yet can achieve significant ROIs through small percentage gains in reject rates.

Packing a Punch

An upgrade to a primary packaging machine on a horizontal form, fill and sealing line demonstrates the importance of considering all sensors in an operation together.

In this case, marginal gains are achieved by ten separate SICK sensing solutions:

An OD1000 displacement measurement sensor determines the wrapping diameter
An MPA position sensor detects the dancer position
A UD18 ultrasonic sensor detects the double layer when splicing
An AX20 array sensor provides accurate edge guiding
A W4-3 photoelectric sensor ensures equidistant infeed of products
A WF fork sensor checks the height of the film
Irregular film edging is detected via a WF23 fork sensor and a MLG2 Prime high- resolution measuring automation light grid
Integrated object and gap measurement when feeding products is achieved with a W4S-3 photoelectric sensor
Reliable print mark detection for registration and orientation is ensured with a KTM Prime contrast sensors

These process improvements might be complemented by upgrades to the machine’s integrated safety systems, including TR10 safety locking actuators and RE1 non-contact safety switches for safe process locking of guard doors. Using the SICK Flexi Soft safety controller ensures safe machine integration with the rest of the production line. SICK Flexi Loop facilitates cascading of the safety switching within SIL-certified safety systems, so cabling is reduced and rapid resetting of safety guarding after approved machine entry, for example for maintenance or in fault finding, is assured.

Safety and Productivity

While these examples demonstrate the possibilities of building up productivity gains using multiple devices and systems, of course it doesn’t have to be a large or complex installation to see benefit from the introduction of even one or two sensing devices.

A widely-used process like automated carton erection may seem simple enough, but, as part of a larger filling and packing process, maximum uptime is essential and can be improved relatively inexpensively while integrating better protection for operators.

In this example, a carton magazine is fitted with SICK WT4 photoelectric sensors to measure the level in the magazine and check the presence of a folded carton prior to it being set upright. Both photoelectric sensors are part of the safety system, using a SICK SafeGuard Detector module on the SICK Flexi Soft safety controller.

An IME inductive proximity sensor monitors the position of the carton at the set-up mechanism, and a SICK IDM260 hand-held laser scanner identifies the correct cardboard packaging and allows validation cross checks of the barcode, so that the correct carton is used for the contents.

In addition to the safety monitoring of the carton magazine, STR1 non-contact safety switches were used on the protective access fencing, again controlled via the Flexi Soft controller.

Relying on Safety

Even the most commonplace of devices can be carefully selected to achieve marginal gains. The new ReLY safety relay was developed to achieve half the response time of comparable safety relays.

A 10ms gain may not be much by itself but incorporated into a safety control function, the speed of response can have a significant impact on the ergonomics of the machine. So, a machine builder can achieve a more compact design, and operators can interact more quickly with their machine, whether it’s a press or a cobot.

The addition of a ‘reset-required’ output to the ReLy relays and on-board diagnostics via an LED status display enables easy maintenance with minimal downtime. The ReLy’s narrow 18mm-wide housing takes up minimal space in the control cabinet, with easy push-in front wiring and a one-click fit-and-release mechanism for simple set-up and quick replacement.

Questioning Assumptions

The same principle of marginal gains holds true for other areas of machinery safety and can prompt us to question common assumptions. For example, when designing safety laser scanners in Automated Guided Vehicles and Carts (AGVs and AGCs) it’s tempting to follow the trend that suggests that technology advances in longer detection fields represent a magic formula for success.

However, smaller protective fields are actually better suited to high output efficiency and space utilisation in a modern production environment. Rapid system safety response times in an integrated safety system enhanced by devices such as safety encoders to control acceleration and braking, can achieve the required safety in AGV operation in a smaller footprint.

So, it’s more important that field sizes are kept to a minimum, by optimising the total response time of the safety devices and associated control system and using scanners like SICK’s MicroScan3 that have the highest possible detection reliability to enable multiple field evaluation without compromising performance.

Evolution not Revolution

Bringing more power to production lines is much less about revolution, than it is about winning through steady, incremental progress. The greatest achievements and inventions of our time from space flight to the light bulb came about through grit and determination to build on previous experience.

Similarly, Industry 4.0 is a battleground that will be won, in the end, one hard-fought step at a time, rather than through a once in a lifetime quantum leap.

Sick (UK) Ltd