Motor manufacturing is recognised as a world-leader in industrial technologies and nowhere is that more true than in the Midlands, the home of the UK’s automotive industry. Now Specsavers has chosen that location to created its own manufacturing centre of excellence.
An optical prescription lab is not something you would naturally link to car making but that is exactly where Specsavers has looked for the expertise to head up the development of its manufacturing hub in Kidderminster.
At the prescription facility, Vision Labs, three of the senior management team are automotive industry experts who have been brought in to apply their experience of world leading production techniques to optics.
Adrian Tune, director of manufacturing and distribution for Europe says the area has a long heritage of automotive manufacture. With Dave Stanton, general manager and Matt Smith, operations director, he says a conscious effort was made by Specsavers to bring in new skills to augment the optical skills already contained within the business. ‘Tier 1 and 2 suppliers to the automotive industry are world class,’ says Stanton, adding ‘we can bring that to optics and improve efficiencies.’
Tune says ideas such as lean manufacturing, process control, just in time, and Kanban all combine to create a toolbox of solutions and ultimately world class manufacture around a single flow. The team is also experimenting with Industry 4.0 techniques which bring together automation data from intelligent machines and cloud computing to create smart factories. Smith says innovation in optical manufacture is on the same path as the automotive sector, it just has a bit of catching up to do.
Big numbers are something you have to come to terms with very quickly on a visit to Specsavers’ Kidderminster cluster of manufacturing and distribution. For example, the total number of spectacles sold by Specsavers in the UK was 11,757,962 in the year to this March. Three major facilities – the group’s Vision Labs surfacing facility, International Glazing Services (IGS) and its lens and contact lens distribution specialist Lens Online live – are all found within a stone’s throw of one another.
Despite the colossal volume despatched by these facilities the group also sees surfacing taking place at Airways Optical near Southampton and distribution from NLRX Hi-Spec Lenses in Kettering. Further manufacturing and distribution centres are found in Guernsey, the Far East and Hungary.
Vision Labs’ surfacing facility generates up to 100,000 lenses each week but Tune is keen to point out Vision Lab’s role within the context of its sister facilities. ‘Between them they provide all of the stock and Rx lenses to all of the UK, Ireland and Northern European Specsavers’ stores,’ he says. Vision Labs produces uncut lenses for stores in the UK, Ireland and Northern Europe. IGS offers glazing for a handful of UK stores and those regions where glazing has not traditionally been the retail optician’s forte. It is clear, both from the capacity of the current plant and the additional space available, that out-of-store glazing is a European trend that can continue to grow.
Satisloh Orbit 2 generators
The third facility, Lens Online, is the Specsavers distribution hub for lenses and contact lenses to its stores and its home contact lens service.
The ethos at Vision Labs is very much as a supplier to Specsavers stores rather than an in house department. Tune says Vision Labs has mechanisms to engage with practices to make sure the quality is right. He says practices do not have to use Vision Labs and can choose to send work to Airways or somewhere else if they want to. ‘That’s the nature of the joint venture.’
All orders arrive at a bank of five printers working constantly to print out the job tickets, 420 every hour, at the start of the process. The order will have been made in store using Specsavers own IT system. Checks are made to see if a job needs to be surfaced or can be fulfilled using a stock lens, says Smith. About 60% of jobs are fulfilled using stock product and the lenses are generally sent straight to the store to be cut and glazed. Vision Labs is there to help surface the rest.
High vacuum coating
Vision Labs is a huge, 4,936 sqm with 330 employees. Purpose built in 1997 it expanded in 2012 to create an adjoining coating facility. Tune says Vision Labs is not just about volumes but quality and scope of product. Vision Labs offers a range of indices, 1.5 to 1.67, and offers a polycarbonate option for safety lenses. ‘60% of what we produce here is freeform,’ he adds. The plant coats around 70% of its output and 65% of those coatings are with the firm’s super hydrophobic, oleophobic, anti-static coating Superclean. Vision Labs also boasts an in-house physicist and a chemist working on lens treatments and evaluating other firms’ coatings in a well-equipped lab.
The production line starts as many others with the job tickets placed in a tray along with one of 104 types of lens which are picked by hand. The lenses are taped – Vision Labs uses a specially-made green tape which has a gap in the adhesive to enable de-taping to be automated more easily further along in the process.
Vision Labs; part of the Kidderminster cluster
The lenses are grouped by type to create batches which can move through the lab more efficiently, the first of many lean processing touches. A bank of four taping machines etches job numbers on the tape and, later, the lens edge, as a double check in case the job ticket becomes separated from the tray. Tune says this is a simple step, and while it has a machine cost, it does not delay the job as it is on the conveyor anyway.
What it does do is cut losses, wastage and improve delivery security. Wherever possible a first-in, first-out approach is taken, allowing a two-day turn around through the plant. A bank of eight blocking machines follows taping, when three sizes of ring can be chosen. The jobs’ barcode is monitored to make sure the lens and block has time to cool before moving to the next process.
Stanton uses this opportunity to demonstrate the Industry 4.0 control desk, known as the cockpit, which takes centre stage on the production floor. Here the data from the production machines are fed in, analysed and charted. It is also displayed graphically on large screens. The team leaders monitor the data to spot problems or optimise the workflow. ‘As we develop it we will be able to monitor quality, efficiency and waste,’ says Stanton. ‘It’s about understanding what the machines are saying and making productivity better.’
Workflow is controlled by computer
Vision Labs also adopts protocols such as Six Sigma and achieves relevant ISO and Investors in People accreditation. The production process is also punctuated with manual and automated inspection checks. ‘The volumes are so high we need reliability and assurance around quality, says Tune.
The generating area is vast. It is split into four main cells containing 21 generators and 25 polishers, a milling and turning step followed by a polishing and fining cell. At the moment one of the cells contains Schneider freeform generation and finishing machines. These are shortly to be replaced by Satisloh Orbit2 generators and Multiflex polishers which will speed the throughput of jobs further. This £1m investment adds to the £2m-£3m invested in the plant annually. ‘Working for Specsavers means we have the latest equipment and investment,’ says Tune.
That investment is evident in the coating facility which sits next to the main generating area, becoming a separate unit from it in 2012. The surfaced jobs make their way here once they are deblocked, de-taped and re-trayed before washing and more quality checks.
The first port of call for many of the lenses is the tinting area where 2,500 lenses a day are treated. A Tec 5 tint measurement machine is used on every lens to ensure consistency of colouration.
Ahead of hard coating the lenses are further chemically etched to ensure good adhesion of the dip coating. The lenses are also sorted to match coatings to the indices of the lens material, polycarbonate being primed to help the coating stick.
Throughout the process the lacquers are checked for concentration and the lenses checked. If the coating is deemed below par the lens is stripped and recoated, rather than discarded, to keep delivery delays to a minimum.
After further washing, quality checks and curing, about 60% of the lenses go on to have a Superclean coating applied. This is carried out in an impressive area where six Leybold high vacuum deposition chambers are constantly re-filled with the carrier domes.
These enable 144 lenses to be processed in each machine. The class 10,000 clean room is staffed by gowned operators filling the coating chambers with granulated chemicals which form Specsavers’ Superclean coating recipe amid more testing and monitoring.
Vision Labs coats around 70% of its lenses output
Once ready for dispatch the lenses are bagged and collated for daily delivery to practices or glazing. Scale again characterises this area which resembles a Royal Mail sorting office with bags for each store loaded up and dispatched. Uncut lenses for overseas stores make their way to Vision Labs’ sister company, International Glazing Services.
IGS started life as a small corner within Vision Labs but has recently been housed (Optician 14.06.17) in a brand new 6,503 sqms unit a few hundred yards from Vision Labs. The role of its 178 staff is glazing frames on an epic scale. Operations director Brendan Graham, another ex-automotive man, reveals that IGS glazes 35,000 frames every week mainly for the northern European market but also for a small number of UK stores.
The Industry 4.0 cockpit
The glazing process for the orders arriving from around the world starts with lens picking which is either taken as the output from Vision Labs or another Specsavers lab. Stock lenses arrive from Lens Online, IGS’s neighbour in the Kidderminster cluster. All frames are traced and trayed accompanied by the ubiquitous barcode before entering processing.
The edging area, the biggest in the UK, uses modern production techniques and heavy investment in the latest equipment to create an efficient flow and an average five day turnaround for practices.
Graham says the firm has been working with MEI since 2013 and conveyors create a flowline production process which eliminates the need for people to be walking around or for trolley loads of trays to be transferred. The clean, spacious and ordered shopfloor uses Biosphera, and is moving to Racer edgers. These use suction to hold four lenses at a time and include auto-inspection.
Industry 4.0 techniques are once again used to optimise workflow, sending trays along specific lines for standard or special, rimless and safety, completion. Quality checking, both manual and automated, takes place again before the completed jobs are cased, bagged and boxed for dispatch.
Inspection takes place throughout manufacturing
Current capacity at IGS is 75,000 to 80,000 jobs a week. If the available space was used and 24/7 working adopted that could increase to 280,000 a week.
Lens Online, the third facility, is Specsavers lens and contact lens despatch unit which is next door to IGS. It covers 3,716 sqm and employs 180 people. It fulfils 25,000 orders everyday sending lenses to practice labs and contact lenses to stores and people’s homes.
Staff are encouraged to suggest ways to optimise workflow
Lens Online also uses the latest techniques to improve efficiencies, such as voice controlled stock picking, to keep track of the 100,000 plus of potential SKUs (stock keeping units) and vast numbers of individual items which are picked and packed each day.
Throughout all three plants there is a big emphasis on the individual, with strong community, environmental and charity activities on offer and reward schemes. All three units boast excellent staff facilities while work-based training schemes are a feature throughout all processes.
Staff are also encouraged, and incentivised, to make suggestions for saving money, improving the environment or optimising the workflow, a scheme which has already resulted in big improvements.