Corrugated packaging is a fast-paced industry sector that runs almost entirely separately to the superficially similar folding carton sector.
Presses, finishing and materials handling equipment are purpose-built or highly modified to suit the unusual demands of the substrate as well as the end customers, who are often retailers with evolving supply chain requirements.
Rigid Containers, backed by its owner VPK Packaging, is moving with the times. Evolving demands of the supply chain in the UK have led it to introduce integrated manufacturing and logistics facilities with large warehousing capabilities, so it can supply a lot of orders ex-stock.
In the past couple of years it has invested more than £20m in corrugated production equipment across its five sites in the UK and Ireland, a figure put into perspective by the fact that they turn over £112m between them. Some 650 people are employed across the five sites.
As part of the equipment investment Rigid’s Desborough site installed a new Chroma Evo 1700 HBL two-colour flexo press, made by Celmacch in Italy. This was ordered to operate with a reconditioned and updated Bobst SPO 1600 automatic flatbed die-cutter from another VPK plant.
“We were looking for a simple printing machine to run in-line with a flatbed die-cutter at a good price,” explains conversion manager Paul Johnson. “The Chroma Evo, Celmacch’s entry-level flexo printer, was a good solution for a two-colour printer in our view.”
The need to increase die-cut capacity at the Desborough plant was the main driver behind the investment. An outdated Eterna flatbed die-cutter was increasingly becoming overloaded with the need to process 8,000 sheets per shift.
At the end of 2014 an under-utilised Bobst SPO 1600 flatbed die-cutter was identified at one of VPK’s sister sites in Aalst. Preparations were made to have the machine refurbished by Bobst.
During the decision-making progress, Rigid looked at installing two print units on the machine and a number of options were explored. Johnson says: “After investigating a number of options, we finally settled on the Chroma Evo on the back of a VPK Group deal. Prior to delivery, we sent key operators, engineers and our print manager over to Italy to view the machine at Celmacch’s facility.”
Rigid took delivery of the print units in mid-November 2015 and they were operational by the end of that month. Celmacch’s staff then trained the operators for a week and a half.
Cellmacch is an Italian flexo press and rotary die-cutter manufacturer. Its Evo models were introduced in 2012 and are intended as lower cost print units that fit below its sophisticated Chroma Print HT Series II series, but still offer high graphics quality together with modern features such as remote diagnostics, direct drive, roll-driven lead edge feeder, as well as vacuum transfer to in-line die-cutters. They are available in 1,700 and 2,100mm sheet widths.
“The Chroma Evo is our entry-level machine,” says Luca Celotti, marketing manager for the Celmacch Group. “This printer is a perfect solution for running high-quality flexo print on a dedicated machine in front of a flatbed die-cutter.
“A lot of companies look for two or three colours in-line and an installation such as the one we have undertaken at Rigid’s Desborough factory is a perfect illustration of how we can enhance the offerings of a standard flatbed die-cutter by adding quality flexo print in-line.
“Considering the high levels of technology and competitive price, box plants can increase margins significantly and see a rapid return on investment.
“The Chroma Evo is equipped with advanced technology, but at the same time, is very user friendly and intuitive for the operator.”
The print unit has fully-independent servo drives, a direct-drive feeder and an upgraded vacuum transport system with precision belts, complete with an automatically controlled adjustable suction system.
Other press features include carbon fibre chambered doctor blades and automatic wash-up. A Matthews fast lock system with double plates, angular skew correction and centre line enable the operator to mount the printing plates in a short time and reduce machine set-up time.
Meanwhile, the Bobst SPO 1600 Autoplaten die-cutter refurbished for Rigid was first built in 1988. The SPO range has been superseded by the latest Mastercut series, but was evidently built to last.
When the possibility of the Aalst machine being adopted came up, Rigid contacted the Bobst customer care centre in Redditch, says Ian Constable, maintenance manager at Desborough. “They confirmed that the machine in Belgium was pretty well kitted out for a 1600, as a lot of the major upgrades had been done in the past. But we needed to be sure that it could achieve what we needed it to.”
A team from Bobst Benelux decommissioned the SPO, then it was moved to a facility in England where Bobst UK engineers could refurbish and upgrade it. The first priority was a deep clean and a full service, says Bobst technical service manager Allan Pinfold. “We followed that with a platen conditioning programme, then the installation of most of the upgrades the plant had chosen, testing that everything was right, and we finished off with a re-spray.”
The platen conditioning was particularly important, says Bobst regional services manager Paul Willer: “The programme removes the build up of oxidation and corrosion on the beams, chases and cutting plates, taking them to close-to-new condition. Once done, it can save operators 15 minutes on every new makeready and two to three minutes on every repeat job.”
Some of the upgrades were second generation, such as a new linear side-guide and lower guillotine system in the delivery, where Bobst has further improved performance from an original upgrade for SPO 1600s. “It gives more positive control of the sheet in the delivery,” says Willer. “That alone could make some jobs run 20% faster than the previous version.”
Linking the two
A transfer station with a dedicated sheet ejector fits between the last print unit and the in-line die-cutter. It prevents the printed surface from making contact with the belts in order to avoid rubbing and helps to control the quality.
This, according to Johnson, has been a great benefit to the company because it means the machine doesn’t have to be stopped during this process. The new machine has also increased output by around 20%, he says.
Bolting brand new press units to an older die-cutter wasn’t without teething problems, Johnson says: “We knew that interfacing a new printing machine with an older albeit reconditioned machine might give us some problems and we did encounter an issue with the transfer section to the Bobst feeder, but a solution was found within about three weeks and fitted prior to Christmas.”
Having an experienced well-established in-house engineering team has been essential according to Johnson, as call-out fees can be on the pricey side. Once the initial problems were solved Rigid’s own engineering staff were able to tweak and change the machine when needed.
The machine has eight hours dedicated to it every two weeks for general maintenance including cleaning and checking the moving parts, ink chambers and rolls.
Undeniably the investment in the Chroma Evo has improved productivity, once problems with the transfer station had been sorted out, according to Johnson. And having the Celmacch/Bobst combination has also enabled the company’s other Bobst SPO 1600 to focus on higher quality work for other customers and allow it to improve its service offering.
Celmacch Chroma Evo 1700 HBL
Process Flexo press for corrugated board
Colours options Two to seven units
Max sheet width 1,700mm
Min sheet width 500mm
Max sheet length 1,200mm
Min sheet length 520mm
Max speed 9,000sph
Corrugated thickness range 1-8mm
Price €750,000 list for two units (about £650,000)
Contact Celmacch Group +39 030 9990480 www.celmacchgroup.com
Rigid Containers has close to 650 employees across five sites, situated in Desborough, Northamptonshire; Selby, North Yorkshire; Wellington, Somerset; Aston, Birmingham; and Limerick, Ireland. In total it turns over £112m. Investments over the past couple of years have added up to more than £20m.
The main clients (around 70% of its business) are own-label food producers that supply short shelf-life foods such as pizzas, ready-meals, soups, salads and desserts for all the major supermarket chains. Healthcare and pharmaceutical markets are also supplied.
Rigid’s parent company VPK has a network of plants in Belgium, Holland, France, Germany, Poland, Turkey, Romania and Ireland. In recent years, it has evolved from a ’product-focused’ business to a service organisation, concentrating on customers’ needs in terms of tailored packaging solutions, supply chain optimisation and just-in-time deliveries.
Why it was bought...
Rigid Containers needed to up die-cutting throughput and installed a Bobst SPO 1600 flatbed die-cutter from another site. During the decision-making process, Rigid came to the conclusion that it should install printing units in-line with the die-cutter. After considering the options, it plumped for the Chroma Evo.
How it has performed...
The combined printer-cutter installation has increased two-colour printed die-cut capacity for the company by about 20% and enabled the company’s other Bobst 1600 machine to focus on the higher-quality print work.