SubscribeWatson-Marlow adds polish to Arista’s printing process with close-coupled lacquer printing pumps.
To refine its Six Sigma-inspired process, Arista Tubes introduced the latest tough, accurate and easy-to-use close-coupled pumps from Watson-Marlow
Lacquer Printing Pumps
Quality improvement programmes are designed around competitive, yet reliable products that help organisations establish customer-focussed processes. One company embarking on a journey of self-improvement is Arista Tubes Ltd, a packaging manufacturer for the pharmaceutical, cosmetic and food industries. It has used the Six Sigma programme to focus on its lacquer-printing area, which formerly relied on a manual-thinning process to control the media’s viscosity, or stickiness.
The Stevenage-based firm has recently updated its procedures to incorporate a fully automated system that significantly improves production efficiencies. Dean Onno, Arista’s Six Sigma implementation manager, is justifiably proud of his company’s achievements.
“We offer a number of special decorations that are applied to tubes after they’ve been lacquered,” he says. “If the surface is wrong, you can’t get the effects to stay on the tube. The new viscosity controller regulates the consistency of the lacquer, thereby providing a more reliable surface. The new system means operators don’t have to thin the lacquer by hand, meaning we’re saving time and money. It’s incredibly important.”
Initially, Arista used diaphragm pumps to deliver lacquer from the newly installed controller to the roller applicators and then back again. However, because the lacquer flowed through the body of the pumps, cross-contamination quickly became a problem.
“When you change from one lacquer to another, you have to clean everything,” Dean says. “Unfortunately, there was no easy way of cleaning the diaphragm pump and it became coated with lacquer, which had the potential of affecting the overall look of the customer’s tube. For instance, the lacquer might not cure properly, or it might not be as shiny as we expected.”
Dean describes the diaphragm pumps as the weakest link in the new system, a position that became untenable when he discovered Arista spent up to £200 a month maintaining the pumps which often failed.
“We had to come up with a solution,” Dean says. “It made sense to move to peristaltic technology, so we looked at three manufacturers and Watson-Marlow came up with the best pump in terms of guaranteeing the integrity of the tube, which was crucial because we wanted to run it continuously.”
Close-Coupled Pumps
With no valves, seals or glands, and the lacquer only making contact with the inside of the pump’s tube, cross contamination was quickly eradicated following the introduction of Watson-Marlow’s high-performance 521 pump in February. The close-coupled industrial circulator also provided a double-headed solution that was able to send lacquer from the viscosity controller tank to the printing rollers and back again.
Incorporating low-friction rollers; a fixed track gap and spring-loaded roller arms to minimise roller impact, the 521 was able to deliver versatile and reliable pumping in Arista’s challenging operating environment. It also featured an easy-grip hub and clutched rotor, which Dean says helped Arista cut contamination and slash changeover times.
“Set-up times have been dramatically reduced,” he says. “In the old days, the pump-cleaning element of a lacquer changeover would take about 20 minutes. With the new Watson-Marlow’s pump, it takes about two.”
He continues: “We’ve also eliminated cross-contamination, which saves lacquer because we’re not disposing of tarnished batches. We’re incredibly happy with it, to the point that we’re spending more money on it.” Two further units have since been installed and an order for three more has been made.
The new pumps indicate the extent to which Arista’s management team is committed to the Six Sigma process – an undertaking that Watson-Marlow is also signed up to.
“I rate Watson-Marlow incredibly highly,” Dean concludes. “They are doing what Six Sigma is all about - they’re heavily into process development and working with their customers to overcome problems with effective solutions.”