Converting

X-ray inspection is moving from simple contamination checking to more sophisticated functions such as weight measurement.

Two new players have entered the UK X-ray inspection equipment market in the past 12 months, providing evidence, if it were needed, that X-ray technology has moved from the sidelines into the mainstream.

In early 2006, by customer request, Germany-based S+S Inspection spread its wings and ventured beyond its core metal detection business into the X-ray arena. “Most of the other metal detector manufacturers – certainly the British ones – offer X-ray technology, and our customers were asking if we could do it. Lots of products are packed in foil trays and metal detection is no good for that, plus they are looking for other contaminants,” says Richard Lines, managing director of S+S Inspection’s UK business, explaining the firm’s reasons for joining the crowded X-ray inspection equipment market.

Then in October, Ishida Europe introduced its IX-GA X-ray inspection system, already a commercial success in Japan, to the European market.

New product development manager Rick Rotkirch says: “We’ve sold X-ray machines in Japan since 1995 and in that time it has gone from us shifting just a few units to a large number of systems. From a price point of view, the machines have come down to quite reasonable levels, so we felt that the European market was mature enough for us to invest in X-ray.”

Differentiation
The reasons S+S and Ishida give for moving into X-ray are plain enough. Less obvious is how these two companies, and indeed other more established players, intend to differentiate themselves in the lively X-ray inspection market.

Ishida says its unique selling point is the machine’s in-built Genetic Algorithm technology. “The machine can learn to look for certain types of contamination, which means it can achieve better detection sensitivity and reliability than machines with standard algorithms, and detection of other types of contaminant won’t suffer,” says Rotkirch. “We believe we are the only company to offer this feature.”

S+S Inspection, meanwhile, says its competitive edge is the fact that the Raycon’s energy source is sited underneath the conveyor, giving it a better detection field. “We also think our imaging software is better because it’s quicker and easier to set up for the product being inspected – it doesn’t need quite the degree of calibration that some systems require,” adds Lines.

One area where Smiths Detection believes it has a distinct advantage is in glass inspection. The firm has recently launched a four-beam X-ray system, which it claims leaves no escape route for contaminants hiding in the bottom of glass jars.

“Current systems are limited because they can’t see round the bottom of a container, so contaminants can hide,” says Terry Woolford, the firm’s manager for product inspection. “If you want 100% coverage, you need a four-beam system.”

He says Smiths has already received orders from two of the world’s five largest baby food manufacturers.

A twin-beam system for glass jars is one of the units in a new X-ray series being launched this month by Thermo Fisher Scientific. “By taking two views of a glass container, you eliminate the hiding places within the container,” says John Stokes, the company’s contaminant detection manager.

The range will also include a single-beam unit for the vertical container market (pouches, cans, Tetra Paks etc).

Stokes says the main difference between the new range and its predecessors is the sophistication of the software. For example, the new machines will incorporate a weight-measuring algorithm, enabling them to function as checkweighers as well as contaminant detectors.

Thermo Fisher Scientific is not the only X-ray company pushing the mass-measurement capabilities of X-ray machines.

Anritsu’s KD74 series of machines, which is distributed in the UK by Selo Bollans, now features a mass-measurement function which will detect product damage and identify where product is missing from a pack.

Loma, part of Spectrum Inspections, has long been extolling the virtues of mass-measurement processing software in calculating individual weights in multi-compartment products. This ‘zonal’ weighing function is particularly valuable for identifying missing components in products such as boxes of chocolates or multi-compartmentalised lunch packs which would go undetected by a checkweigher.

But do food companies actually want an inspection machine that can verify product weights and identify missing items, or do they just want a machine that does ‘what it says on the tin’, namely, find contaminants?

Smiths’ Woolford is adamant that multi-functional systems are what users are looking for, saying: “More and more people want additional value from their systems – it seems there’s a move towards integrating X-ray into process control.”

For example, Smiths has supplied dozens of X-ray systems to UK food plants to effectively carry out the combined job of a metal detector and checkweigher. “The machine operates as accurately as a checkweigher, but fits into a much smaller line length, as it replaces both a checkweigher and metal detector.”

Using an X-ray machine to fulfil the role of contaminant detector and checkweigher also takes some of the sting out of the cost of X-ray, because although the technology has come down in price in recent years, it is still pretty steep when compared to the more modestly priced metal detector.

Another ‘value adding’ function that can be carried out by Smiths’ units is the detection of product caught in pack seals.

“By using one of our systems at the end of the packing line, it can tell the user if they’ve got product trapped in the seal before the seal degrades. Supermarkets will return a whole shipment based on one or two leakers,” explains Woolford.

Back to basics
But while some manufacturers and packers might be impressed by such clever functions, they aren’t for everyone.

Many equipment manufacturers have spent the last few years working hard to shake off perceptions of X-ray equipment as ‘complicated’ and ‘difficult to use’.

Ian Robertshaw, sales account manager with Mettler Toledo Safeline, says: “If you go back five years, X-ray machines were very complicated to set up and it was difficult to get reliable performance out of them.”

With its latest system, the AdvanChek, Mettler Toledo Safeline has gone back to basics. “This machine is purely a contaminant system designed around food industry requirements,” explains Robertshaw. “We’ve taken away the functions that a lot of firms, to be completely honest, don’t use. I’d say it is for somebody in the ready-meals industry who is being pushed by a retailer to start doing some proper contaminant detection on a foil package, who doesn’t want mass-measurement, just a reliable contaminant detection system. The only thing the operator has to input is the belt speed and the name of the product. It’s taken away the need for expertise in X-ray technology.”

He insists, however, that this simplicity doesn’t mean performance is compromised. “It still delivers a high level of contaminant detection performance,” he says.

There are some applications in which an X-ray system’s extracurricular capabilities are justified and useful. However, as the technology matures, in the majority of cases, packers and manufacturers still want the same things they have been seeking for years – reliability, ease of use and accuracy. And with a flurry of innovation at the ‘basic’ end of the market, it looks like that isn’t too much to ask for.


Case Study: Healthbars Unlimited
Simplicity was a key requirement of Healthbars Unlimited when it contacted Loma-Cintex in search of an inspection product for its cereal, fruit and nut, energy and carob bars.

Healthbars Unlimited knew it needed to go further than a conventional metal detector, because stones and other contaminants from the fields occasionally come in with organic fruit, nuts and seeds, but wasn’t keen on paying X-ray detector prices.

Loma recommended its XR X-ray system, a low-cost unit that is priced in line with many metal detectors. The system is capable of detecting ferrous and non-ferrous metals, glass, stones, ceramic, cement, calcified bones, high density plastics and rubber.

It uses the same computer electronics and user interface as the Loma-Cintex range but includes a new, low-power WASC (wide-angle, self cooled) X-ray design which has fewer moving parts and occupies minimal space. With an overall length of 1.8m including integral reject system, the XR unit fitted into the limited floor space available.

Ease of operation is assured by a clear backlit LCD with simple touchscreen controls.

“The XR fitted all our requirements in terms of affordability, reliability, ease of use and the fact that it doesn’t take up too much space,” said Vince Handley, general manager of Healthbars Unlimited.