Pump Metering Accuracy Contributes to Product Excellence at Historic Paper Mill

St Cuthberts Mill is a master papermaker with a heritage that can be traced back to the 1700s. Based near Wells in Somerset, England, St Cuthberts specializes in the manufacture of high-quality artists’ papers. The company makes approximately 80 tons of paper every month using a continental shift pattern across 24/7 operations. The secret of the company’s success lies in the performance of its papers, which can be used for watercolor, printmaking, or inkjet use.

A Qdos pump in use at St Cuthberts Mill.

“Reliability is the key to our output,” states the company’s shift manager, Paul Tremlett. “As a result, we need pumps that perform reliably, day-in, day-out.”

Until recently, St Cuthberts used a series of older peristaltic pumps, some of which were installed 20 years ago. Recently, the mill switched to Qdos pump technology from Watson-Marlow Fluid Technology Group for metering substances such as pigment and starch.

Since installation, the Qdos pumps have run with complete reliability, boosted precision considerably, and saved thousands of dollars due to precise shade and chemical addition control, plus the reduction in downtime associated with a previously deployed pump.

“We wanted to move into the 21st century, and knew that the Qdos pumps could offer us a number of key advantages,” says Tremlett. “For instance, the pumps can be linked to the machine’s control system, so we can change speed accordingly.”

The company currently has two Qdos 120 pumps and two Qdos 30 models for metering of pigments and starch, with two more Qdos 30 pumps on order. What’s more, all papers produced by St Cuthberts are internally sized to increase strength. This process involves the addition of a special chemical—also pumped using Qdos technology—to make the sheet stronger and eliminate any possibility of blotting effects.

Qdos pumps are self-priming and reversible, so fluids can be returned to their source at the end of a shift. The pumps’ design inherently reduces maintenance since operators can quickly and safely replace one component, the ReNu pumphead, without the need for tools or special skills. Cleaning times are also minimized, thus delivering further efficiencies to the St Cuthberts team. Crucially, from a health and safety perspective, integral leak detection reduces waste and eliminates mill operator exposure to chemicals.

“The machine crew here loves the Qdos pumps because they are so reliable; we’ve not had a single glitch even when handling the abrasive starch. The pumps offer high accuracy metering, which helps maximize trust in the product,” states Tremlett.

Flow rates from 0.1 to 2000 ml/min at up to 7 bar can be achieved using Qdos pumps. Importantly, simple drop-in installation eliminates the need for ancillary equipment, which often brings with it further maintenance challenges and costs.

The pumps were provided by Watson-Marlow Fluid Technology Group (WMFTG), an international operation based in Falmouth, Cornwall, UK. Founded on nearly 60 years of supplying engineering and process expertise and with more than one million pumps installed worldwide, WMFTG comprises 10 established brands, each with its own area of expertise. WMFTG is a wholly-owned subsidiary of Spirax-Sarco Engineering plc, a global organization employing approximately 4,800 people worldwide. In 2017, WMFTG received the Queen’s Award for Enterprise: International Trade.

Russell Merritt is marketing manager at Watson-Marlow Fluid Technology Group, a world leader in niche peristaltic and sinusoidal pumps and associated fluid path technologies. Learn more at www.wmftg.com.