20 July 2016 Digital Printing Technologies

Digital charts the waters for UKHO

The need for quality and precision in the printing of navigational charts is paramount – even small errors such as a misplaced dot could be a matter of life and death at sea.

Despite the availability of digital information, GPS and satellite navigational aids, along with the growing popularity of Electronic Navigational Charts, the printed product retains its place.

Standard Nautical Charts are the tangible outcome of work at the United Kingdom Hydrographic Office in Taunton. This is still a trading fund of the Ministry of Defence, providing operational support to the Royal Navy, but is also a pioneering technology company in its own right.

Under the Admiralty Maritime Products & Services brand, the UKHO is a world-leading provider of hydrographic and geospatial information, with a comprehensive range of Solas compliant charts, publications and digital services.

UKHO’s print department is currently housed in a vast building, along with a world-class team of hydrographers and cartographers - those gathering the data about repositioning of buoys, lights and other navigational aids. As well as Admiralty branded charts, UKHO publishes an extensive range of books, some with small circulations, others running to 45,000 copies and into multiple volumes.

But things are changing. The whole operation plans to relocate to a new unit when the UKHO completes construction of its new office building on the existing Taunton site. It has shifted production of books to Latimer Trend in Plymouth, while the printing of Admiralty brand charts will remain with the UKHO in Taunton. However, its two large format litho presses have been switched off and production of up to 10,000 charts a day will henceforth be digital.

The last litho printed charts are in the warehouse waiting for shipment to any of 140 Admiralty Chart Agents around the world.

They in turn distribute the charts to the 42,000 ships at sea that are legally obliged to carry a complete set of SOLAS compliant charts for every voyage, from wide area charts for the open sea, to detailed versions for the approach to ports. Stocks are being reduced as UKHO adopts a print on demand model rather than printing to replenish stock levels.

For much of the time that UKHO has relied on a Man Roland 900 and a large format Mitsubishi for printing the bulk of the charts, it has been exploring the options for digital printing, says production manager Paul Kelly. “We had been looking at digital technology for 12 years. We started with 12 Epsons which could produce three A0 charts an hour when just 3% of output was digital,” Kelly says. It was quite possible to fold these by hand because of the limited speed of production.

This approach was replaced by three much faster single-pass Vortex 4200 machines using Memjet printheads, and digital became 33% of production. Now these have been replaced by five HP PageWide 8000 printers able to print a chart every six seconds, and the litho presses have finally been retired.

“We became close to HP, and discussed investment in the T400 web press, but we would have needed two,” says Kelly. “That led to us becoming a beta site for the PageWide 8000 from August last year. We had already decided we would need inline folding and signed a contract for this with MBO.”

Kelly is also at the point of retirement, handing over to Tom Scott-Clarke, a cartographer rather than printer by background, but who is equally as passionate about the products he is now in charge of delivering. “The books are a standard format product, limp or case bound, which we put out to tender, whereas chart production is very bespoke,” he says. “We considered all the options, including reinvesting in litho.”

Instead, UKHO has come up with a unique solution that involves printing and fully automated inline folding so that each chart can be completely different in terms of content and folding configuration, and the finished article is delivered ready for its box according to the order from one of the Admiralty Chart Agents.

There were deep discussions about the exact requirements and how the dynamic folding units would work. UKHO needed to retain the bespoke format it has used for each Admiralty brand chart for many years. The format has become ingrained in the shipping industry, with vessels having racking on the bridge designed around the size of each chart.

While it might have been easier to switch to a standard format, it was important for the UKHO to continue to meet the requirements of its end users, who are the mariners responsible for the safe navigation of the world’s ocean-going fleet of ships.

But it was possible to reduce the variety of folding combinations. There are now 14 variants that will be folded by the inline T1420 MBO buckle folders. The few that fall outside continue to be folded by hand.

When moving to the Vortex dye based inkjet, UKHO had to specify a paper to ensure crisp rendition of the numbers indicating depths, reefs and rocks and that would also be waterproof. This resulted in a bespoke paper that is durable enough to be used for at least a year at sea. That paper became the standard and was used on the litho presses. It continues with the PageWide machines.

Each roll is 130 metres long, though the aim is to use 125 metres of this, as it cannot afford to have a roll run out mid-way through printing a chart. The method of delivery poses its own problems as the flatness of the sheet will vary from start to finish of each roll, and both printing and folding need to cope.

A chart takes six seconds to print and includes a 2D matrix to identify each and to adjust the two sets of buckle plates if needed. A scanner, after printing, checks quality ahead of folding, rejecting and reordering sub-standard prints as necessary. Every 50 charts, a test sheet is printed to ensure consistency of inkjet operation.

An identification line is printed on the underside of each chart using a Scitex print head. This labels the chart and its production date. The navigational data on charts can quickly change if shipping lanes change, if new hazards are identified or if new port facilities are built. Such ports can be staggering in size, Scott-Clarke points out, and there is no shortage of new port development and expansion to support the shifting patterns of global shipping.

It means a steady flow of work for UKHO as charts are updated. The matrix code is unique to each chart, even where a batch of the same product is printed. This also helps to reassure users that they are using genuine Admiralty brand charts, and not counterfeits. Such fraudulent activity is considered low level but the UKHO remains actively vigilant, given the potential risks to the safety of shipping that counterfeit charts can pose.

The chart is turned through 90º to present the short edge to the first set of buckle plates. MBO has previously built dynamic folders for smaller formats, producing stitched booklets for example, or for inkjet newspaper production. A second buckle section results in the finished product ready for boxing up.

It is not a low cost operation. Each folder is a £750,000 investment. There are five HP PageWide 8000s. Any two are in permanent readiness should one of those linked involved in the operation fail. The spare is used to print the few charts that fall outside the standard production process.

Each line has its own server, and again there is a spare PC ready to be swapped over when needed. This happens regardless of requirement every three months to balance the life of each PC and to ensure contingency, with consignment stocks for spares held on site.

Each server will be loaded with the next ten jobs at any point. As a chart can be 40Mb or more in its print ready PDF state, there is a heavy ripping and file management requirement. This was initially beyond the HP SmartStream server and, like the MBOs, has needed bespoke intervention to ensure it could meet UKHO’s needs.

The production for each day is pulled from the database in readiness every morning. This will make it far easier for the operation to relocate when the time comes.

Monitors on the walls of the production floor will show the schedule for the day as well as tracking orders and the production process. Orders are received from the Admiralty Chart Agents around the world, then filtered and sorted automatically.

Again this has required bespoke software. UKHO continues to hold many charts in stock to be picked to order, however these will gradually be replaced by print on demand production, releasing even more space.

This is just one of the advantages of the new process. The biggest gain is in sheer efficiency. There are 3,500 Standard Nautical Charts that can be ordered and by using inkjet technology, it will be possible to print every one of these to order. “With litho we would not have been able to print everything in the same week, or even the same month,” says Kelly.

For Scott-Clarke, the speed of response to customers is of great importance. “There used to be a seven or eight day turnaround to put new charts in to stock, producing the plates, print and finish and then to land into stock. Now that can be done in 20 seconds.

“With changes to a chart, it is important to get that information to mariners as soon as possible. We run this operation with 18 fewer people than before, achieved through either retirement or by being redeployed elsewhere.”

The offset presses were used for runs above 150 copies. Apart from the 20% wastage at make ready, the risk that changes would make charts in the warehouse worthless was always high. The items held have more than halved from 500,000 to 200,000, more so with the transition to digital printing.

Digital is also a cleaner process. The operation might have used 2,500 plates a month, with the chemistry required, the inks and the fount solutions and cleaning solvents associated with printing. All of this has now gone. Cost of digital production matches that which was achieved by litho says Scott-Clarke.

Kelly can be satisfied that as he retires he hands over a lean, highly automated production operation that is fit for purpose, as the UKHO embraces the needs of its customers in the digital era. Scott-Clarke will move it on again, maintaining a 200 year heritage of helping to keep mariners safe at sea, rather than on the rocks.

« »
Digital charts

Digital charts

There is still a strong demand for printed charts, but instead of printing hundreds of copies for stock, UKHO now tries to print on demand in order to minimise the need to throw out charts when the crucial information they contain changes.


Explore more...

Where to buy navigational charts

Story 1 of 3

MBO folder

MBO folder

MBO had to develop new folder technology for the UKHO project. It had automated the set up on smaller format folders, using in line with inkjet web press for example, but never before had it built a folder to this scale.


Explore more...

MBO's folders

Story 2 of 3

HP PageWide XL8000

HP PageWide XL8000

The Taunton site became the beta site for the high speed wide format printer last year, choosing to replace Memjet powered inkjet printers. UKHO prints on a specially developed paper which retains the fine detail on the charts and which is impervious to water damage.


Explore more...


HP's PageWide 8000 XL printer

Story 3 of 3