In the aftermath of drupa 2000, the sleeve machine combined with servo drive technology has replaced all other well-known systems on the market. In the range of medium material widths (800-1500mm) the old technology with fixed cylinders and robots can no longer keep up with market demands.
Sleeve machines from all manufacturers have the following in common: a so-called basic shaft that is permanently fixed into the drive side of the press in order to guarantee optimum precision and registration. The sleeve support system or intermediate cylinders are then locked onto these basic shafts, which normally have an outside diameter of approximately 100mm. Over certain repeat lengths it is important that the print sleeve is supported by a mandrel and not by a piggyback type sleeve that has many tolerance variables and can be costly and labour intensive. In this system the intermediate mandrel therefore plays an important role.
The selection of material is very important as this determines weight, printing speed and above all the print quality. Materials like steel, aluminium or fibreglass prove to be unsuitable as the intermediate mandrels would be too heavy or unsuitable for good print results with high printing speeds (up to 600m/min).
Fischer & Krecke is the only flexo press manufacturer in the world offering a sleeve system able to match the performance of the new servo driven, gearless systems. It offers Flexpress Carbon, the patented bridge sleeve system that the company says does not compromise on quality.
The use of carbon material and the design of its bridge sleeves guarantee a speed increase of up to 40 per cent compared to conventional bridge sleeve systems, says Fischer & Krecke. Flexpress Carbon not only allows increased production rates, it also delivers outstanding print quality. Moreover, the light material weight allows the easy and efficient sleeve handling needed to keep changeover times and manpower requirements at the barest minimum. These benefits are offered in all widths including the mega width formats employed in the company’s largest linerboard presses.
Fischer & Krecke says Flexpress Carbon offers the advantages of high flexual strength for outstanding print results and high output speeds; damping behaviour for lower vibration and bouncing tendency; low specific weight for easy handling for wide widths and fast change over times; and minimal thermal extension, for consistency high print quality at all temperatures.
One company very pleased with the quality and output of the Fischer & Krecke solution is the New Zealand branch of FPSInternational (FPSI), which recently installed an eight colour F&K 16s flexo press, as well as a complete ink system upgrade of its existing F&K 34DF.
Roger Kirwan, FPSI Australasia general manager, says, "The 34DF is a very good press, and on the basis of the 34DF, we then went with the 16s. Both are very solid and reliable machines, with the added advantage of the 16s being that it offers quick changeover.
"With the new press, it has given us the ability to swap the jobs over if needed, moving the jobs that require longer runs to the 34DF while keeping the jobs that require quicker changeover to the 16s. This has given us much more flexibility, as well as a definite increase in production, particularly because the newer machine is just so much faster."