Materials Handling


screen print that colour the images on thousands of everyday products - from retail displays, textiles and packaging to CDs and DVDs. Over the course of the past decade, particularly in the


past 3-4 years, changes in the wide format digital ink market have seen FSIS respond to maintain its position as a UV technology leader. Today, every process at the plant needs to be ultra efficient


and 100 per cent reliable in order to meet high customer demands. “We have a bead/dispersion mill that effectively comprises


a six litre capacity, water-cooled horizontal chamber,” explains the company’s productivity services manager Trevor Cornock. “Inside the chamber are a number of very small beads made of hard-wearing yttrium stabilised zirconium that measure 1.6-2.4 mm in diameter. These beads are deployed to grind the pigment being milled.”


Productivity Although this sounds straightforward enough, Fujifilm SIS encountered an unexpected problem that due to its repeated nature began to have a significant effect on productivity. “A certain viscous ink component we use has a UV


monomer type base that may cure when exposed to temperatures above 50°C,” says Cornock. “Because our previous AOD pump generated a fair amount of friction, this converted to heat and caused the ink component to turn from liquid to gel when temperatures exceeded 60°C, which would eventually bring the bead mill to a halt.” It was clear FSIS required a pump that generated minimal


friction and so could avoid the associated heat problems. As an existing supplier to Fujifilm SIS (formerly Sericol),


Watson-Marlow was able to recommend a solution in the form of its MasoSine SPS series, a highly reliable and economical positive displacement pump for industrial applications. Its design features an exclusive sinusoidal rotor that overcomes the limitations of conventional rotary lobe pumps (Fig. 1) to produce powerful suction with low shear, low pulsation, gentle handling – and, most importantly for FSIS, very low friction. The MasoSine pump has been installed for around nine


months and FSIS reports no problems whatsoever. This is aided by the low maintenance design of the SPS series. With a single shaft and rotor, there is no need for the complex timing gears and multiple seals associated with conventional rotary lobe pumps. One rotor, one shaft and one seal equate to simple and economic maintenance.


Wider peristaltic applications According to Verderflex, the growing awareness of the peristaltic pump’s wider potential is leading to its increased use in less arduous fields of application. It is regularly specified by the printing and packaging industries in place of air diaphragm pumps as it is gentle on the product but still able, for example, to handle viscous metallic inks. The food, drink and pharmaceutical industries are also regularly installing this type of pump. This is because the pumped product is isolated from the workings, there’s no danger of contamination and it’s easy to sterilise. Another key factor in the rising popularity of the


peristaltic pump is its fit-and-forget quality. Its lack of valves, seals and glands makes it inexpensive to maintain. Indeed the only replacement part on a peristaltic pump


is the hose or tube, a relatively low cost item that is easily exchanged. These, say Verderflex, are important qualities as


companies strive to optimise production processes and minimise costly downtime. As well as improved design, the company says that


developments in tube and hose technology have a significant role in the peristaltic pump’s wide application scope and high reliability. The choice includes resistance to high temperatures,


corrosive chemicals, oils, fuels, solvent and mineral acids and of course includes special grades for food, drink and pharmaceutical handling tasks. Advances have also been made in the way hoses are manufactured. Historically hoses would fail due to early fatigue. The rubber layers and the reinforcement layer become


dis-bonded, a process that is often accelerated by externally machining the hose to achieve equal wall thickness. However, a new hose production process has been


The benefits of multi-channel pumping A


ccuStaltic pumps are reliable pumps that simply squeeze the liquid out of a flexible tube, with precision rollers, in a continuous or cyclic rotary motion. The fluid only contacts the inside of the resilient tubing. These types of pumps are called peristaltic tube pumps and AccuStaltic pumps are specifically designed to use multiple tubes simultaneously. The pumps range from 4 to 12 individual flow channels which can be combined with different manifolds and tubing to create flows from single continuous flows up to 180 litres/ minute to 12 accurately metered individual


32 www.engineerlive.com


flows of as little as 0.5ml per cycle. AccuStaltic pumps are self-priming, non- cavitating, and can be run dry with no pump damage. The company says multi-channel peristaltic pumps have a host of benefits over the competition. In terms of accuracy, for example, they work at ±5 per cent of average flow over its speed range and the life of the tube for most tubes. Most others have to be hand-calibrated and verified each channel, each time.


Similarly with product contamination


issues, AccuStaltic’s double-sealed, synthetic-lubed bearings are impervious to


contamination. All parts are stainless steel or coated to resist all but the strongest alkali solutions. Competitor pump rollers can become contaminated and seize, causing premature failure. Also, painted/plated steel and plastic become susceptible to UV and chemical degradation.


The company also boasts ease of servicing, with only four or fewer bolts needed to remove any component. In addition, all parts available, individually, off-the-shelf. Competitor pumps are often built to be disposable, or integrated with a drive motor, which limits serviceability. ■


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50