MechChem Africa talks to Darryl MacDougall, Managing Director of Verder Pumps South Africa, about recent innovations: the newly designed Verderflex Dura 65 peristaltic hose pump; the Verderair e-PURE electrically driven double diaphragm pump; and the addition of JABSCO Rotary Lobe pumps for the food, beverage and pharmaceutical markets.
While Verder Pumps South Africa (VPSA) is a sub-division of the global Verder Group company, Verder Liquids, the local entity has played a key role in the development of the company’s products, most notably its Verderflex Dura range of peristaltic hose pumps for the mining and minerals processing industries.
“Just to take you back in history a little, Verder Pumps South Africa was instrumental in developing the Verderflex Dura pump range, up to and including the Dura 55,” begins MacDougall.
“Daan Louw of Verder SA was instrumental in assisting the factory in the United Kingdom to design the Verder Dura range so that it met typical mining requirements here in South Africa. In addition, our previous South African Marketing Manager was the originator of the Dura name and she was given the responsibility of launching the VerderFlex Dura pump range into Europe.
“So VPSA played a key role in one of the global group’s flagship products.”
In recent months, Verder has launched an upgraded Dura 55 HF, which has a slightly larger internal hose diameter that drops the pressure a little to give a better flow rate. “This is a new hose combination rather than a new pump design, and this pump remains essentially the same as the one developed using Daan Louw’s input,” MacDougall says.
Earlier this year, however, a completely redesigned Verderflex D65 was launched, which is the latest evolution of the Dura range and will soon replace the Verderflex VF65.
Verderflex Dura 65
Verder’s new D65 peristaltic hose pump has exactly the same footprint as its predecessor, but offers 20% better flow rates, and this has been achieved by lengthening the swept volume of the hose. “The internal geometry has been changed so that the shoes make contact with the hose 20% earlier, which results in 20% more volume being pumped through the hose per stroke,” explains MacDougall. “We’ve also changed the gearbox and rotor mounting so the gearbox no longer carries the full rotor load. We have done this by adding an internal bearing and bearing housing to fully support the rotor that drives the shoes around the peristaltic hose. We have also changed the drive shaft sealing arrangement so that, should a hose burst, the slurry being pumped is prevented from entering the pump’s gearbox,” he explains, adding that this improves the lifespan of the gearbox and solves a problem that has long been associated with all peristaltic pumps.
“The design change also enables us to easily replace the gearbox with a smaller gearbox , for lighter dosing duties, which was not possible on the previous version,” he continues.
The new design, which uses the same hose as the VF65, also extends hose life by 20%, resulting in downtime and maintenance cost advantages. “Through better all-round engineering design, the D65 delivers much better pumping performance at lower than ever costs of ownership,” argues MacDougall.
Other new design details include: an access hatch to clean the hose track; a lifting eye on the front plate to make the unit safer to work on; a ball valve on the drain port; and an angled metal filling port for the glycerine hose lubricant. “These small improvements all deliver operational advantages without impacting value for money,” he tells MechChem Africa.
He further reveals that the success of the D65 development is being followed up by the replacement of the VerderFlex VF80 pump with the Dura D80. All the same advantages will be offered at a higher flow capacity, with the new D80 using the same hose sizes as the VF80.
Another novel Verder solution in the pipeline that hasn’t yet been released to the market is the Verder DS5000 tube pump for precision dosing. “This will target minerals processing markets where accurate quantities of reagents such as flocculants need to be added for applications such as underflow thickening or flotation,” notes MacDougall.
The Verderair e-PURE diaphragm pump
On the diaphragm pump side, MacDougall says a new Verderair e-PURE electrically driven double diaphragm pump has also just been released. “We have long been a specialist in air operated diaphragm pumps, but this version is electrically operated. It means that an air supply is not needed for operation, which improves reliability and reduces running costs significantly.”
“We call these ‘PURE’ pumps because the wet-end is manufactured from pure materials chosen for their temperature, abrasion or corrosion resistance: pure polypropylene or PTFE, for example. The pure materials are also very easy to clean as they tend not to get impregnated with slurry media,” he says.
On the new Verder e-PURE pump, the ball check non-return valve typically used on diaphragm pumps has been replaced with a flapper valve, which is better for pumping slurries or media containing solids. The biggest pump in this range can handle 100ℓ/min (6.0 m3/h) and there are material options for a number of exotic liquids.
Citing an early success, MacDougall says four of these pumps have been sold to a copper processor in the Congo to pump sulphuric acid wash-down waste from a sump. “In this application acid spillage from delivery vehicles is washed down into a sump. Our e-PURE pumps are being used to transfer this toxic slurry into waste collection vehicles. The highly corrosive acid can get extremely hot due to the exothermic reaction with the washdown water, and it also picks up grit, which makes our new e-PURE solution with its flapper valve and PTFE contact material an ideal pump for the task,” he tells MechChem Africa.
JABSCO rotary lobe pumps
In addition, MacDougall points out that Verder recently acquired the JABSCO rotary lobe pump business. “This gives us a stronger offering for the local food, beverage and pharmaceutical markets, where clean-in-place/sterilise-in-place routines are essential for hygiene and food safety.
“Rotary lobe pumps are ideal for transferring viscous substances such as peanut butter, yeast and mayonnaise. They are manufactured to hygienic standards using polished 316 stainless steel and we can offer various combinations of mechanical seals to cater for a wide range of media types,” he notes. Looking at future growth potential, MacDougall points out that the water and wastewater industry could benefit significantly from Verder’s dosing experience in the mining and minerals processing industries.
“To add reagents to thickeners and clarifiers, the water and wastewater industries have, for many years, relied on progressive cavity pumps. We have had experiences where 15% of the flocculant being used at a plant was being lost in the progressive cavity pump being used.
“By using a small cost-effective peristaltic hose pump, which will prevent flocculant shear just as well as a progressive cavity pump, the cost of maintenance will reduce significantly, dosing accuracy will improve and the amount of wasted flocculant will decrease dramatically,” he suggests.
“Using our pumps, we can far more efficiently manage dosing applications at wastewater plants, just as we do on the Copper mines in DRC where we have racks of Dura 25s being used to dose reagents at massive flotation plants. We have the modern solutions that wastewater treatment plants need, and it is a business area we are very interested in growing,” MacDougall concludes.
