Short Run Packaging: Intermittent Offset or Digitaltest
By: Mr. Ranesh Bajaj
The shrink in print volumes and move of more jobs to digital has been driving change and a number of commercial printers are moving into packaging field. With Labels and packaging still sustaining reasonable growth rates, this market seems to hold some future though crowding is likely to occur soon enough here as well.
Within the general field of packaging, short runs or just in time packaging solutions seem to hold a niche market area with considerable promise. The challenge only is to address the market with right technology.
VINSAK LIO350 Intermittent Offset Shaftless Press
VINSAK L400 Digital Color Label Press
In order to define the parameters to conduct a comparable study for better selection between these two technologies let us first decide on these.
A typical short run Label job is 5000 Labels or 5000 cartons. Let us take a size of each product to be 200mm X 250mm. Though for a Label this seems to be a little large in size, for cartons in most applications, this is a standard size and for the purpose of comparison this will be an ideal size.
A typical web width of Digital Label or carton press will be 330mm and hence for the intermittent offset we will stay with this web width itself. Based on this web width, such a job as above would be in linear meters 1250 Linear meters of Substrate.
Most digital presses (With the exception of the latest generation of UV ink jet presses) work at a press speed of 10 to 12 meters per minute when running in the 6 or 7 color mode. Based on a set up time of say a max of 10 minutes per job, and a running time of 125 minutes for 5000 pcs (of size 250 x 250 mm), a total process time of 135 minutes per job is achieved. Assuming 8 hours of running and 25 days in a month, a printer will be able to deliver 3.5 Jobs per day or 90 Jobs per month.
An intermittent offset press on the other hand works at an optimum press speed of 40 mts/min (Max mechanical speed being 70 mts/min). Also the set up time on such a press for a 7 color job with automatic inking and automatic register would be 40 minutes and a running time of 31 mins (considering the same job of size 250x250mm with volume of 5000 pcs.), a total process time of 71 minutes is achieved. Keeping the 8 hours per day running and 25 days in a month, a printer would be able to deliver 7 Jobs per day or 175 jobs per month.
To find out your process times for typical jobs, log on to www.vinsak.com/jrtc.xlsx and download your own job run time calculator.
A typical digital press in this day and age costs say USD 900K and a typical Intermittent offset press costs USD 600 K, the per hour cost of the digital press continues to be 1.5 times that of the offset. On top of the same the running cost of a digital press continues to be at least 4 times higher than an offset press after catering to set up waste, origination costs and click charges or cost of consumable.
A deeper detailed study into this market would further reveal that for runs length of up to 300 linear meters on the digital press, the cost of digital is lower than or equal to offset and for higher run lengths offset continues to be cheaper. It is therefore essential for a printer to do an in-depth study of the run lengths of the jobs that are available in the market and then decide on the technology that suits him best.
As markets mature and technologies evolve, these comparisons will continue to be tweaked scenarios will change, but in the current highly competitive market scenario, it is essential for the printer to make the right choice to survive and thrive.