Kamp-Lintfort, Germany – October 23, 2017 – Quattroflow^?, part of PSG^?, a Dover company and a leading brand of positive displacement quaternary diaphragm pumps, offers a full line of quaternary diaphragm pumps ideal for incorporation into Tangential Flow Filtration (TFF) systems used to concentrate and diafiltrate target protein solutions during the “downstream” purification stage of biopharmaceutical production.

Also known as cross-flow filtration (CF), in TFF the feed stream flows tangentially across the filter membrane at positive pressure. As it passes across the membrane, the portion of the feed stream that is smaller than the membrane’s pore size passes through the membrane (called permeate). This is different than other filtration techniques because the tangential motion of the fluid across the membrane prevents molecules from building up a compact gel layer on the surface of the membrane. This mode of operation means that a TFF process can operate efficiently with relatively high protein concentrations with less fouling or binding of the filter.

To scale up a TFF process there are two variables that need to be successfully controlled. Recirculation (cross-flow) is required to minimize formation of the gel layer and pressure as the driving force to push the permeate through the membrane. The recirculation rate needs to work in conjunction with the pressure. Maintaining a constant trans-membrane pressure (TMP) is critical because if it is too high it can cause gel-layer formation that cannot be removed by recirculation, and if it is too low it results in low flux that will reduce process efficiency. So, a critical step in guaranteeing an efficient, reliable and cost-effective operation is found in identifying and using a pump technology that is capable of producing both low-pulsation and low-shear operation despite varying flow rates and pumping pressures.

Quattroflow pumps – which are available in QF150, QF1200, QF4400, QF5050 and QF20K sizes – are perfect for this application because their four-piston/four-diaphragm method of design and operation delivers the consistent flow control that is essential in producing optimal filtrate yields. The Quattroflow design also provides low pulsation, gentle product handling, a large turndown ratio, high flow-rate accuracy, low noise and a compact construction. Additionally, all Quattroflow pump models also offer the option of single-use configurations with replaceable plastic heads, which eliminates the need for time-consuming cleaning between batches. This increases the product’s speed-to-market capabilities, which is a crucial consideration when attempting to maximize the product’s availability within its patent window.

For more information on Quattroflow, please go to quattroflow.com. Quattroflow is a product brand within PSG, a Dover company. For more information on PSG, please go to psgdover.com.

About Quattroflow: 
Quattroflow^? is a leading brand of quaternary (four-piston) diaphragm pumps that primarily serve industries such as pharmaceutical and biopharmaceutical that require gentle displacement, reliability, product safety, purity and cleanability. Headquartered in Duisburg, Germany, Quattroflow is part of PSG^? , a Dover company. For more information on Quattroflow and its complete family of four-piston pumps, please visit quattroflow.com. For more information on PSG and any of its leading brands, please visit psgdover.com.

About Dover Corporation:
Dover is a diversified global manufacturer with annual revenue of approximately $7 billion. We deliver innovative equipment and components, specialty systems, consumable supplies, software and digital solutions, and support services through three operating segments: Engineered Systems, Fluids and Refrigeration & Food Equipment. Dover combines global scale with operational agility to lead the markets we serve. Recognized for our entrepreneurial approach for over 60 years, our team of approximately 24,000 employees takes an ownership mindset, collaborating with customers to redefine what's possible. Dover is headquartered in Downers Grove, IL, USA.

Marketing Contact:
Rainer Frericks, Director of Marketing 
PSG^?, a Dover company.
+49 2065 89205-0 513-280-0047 or Rainer.Frericks@psgdover.com

Media Contact:
Darren Wight, VP Media & Publicity
DeanHouston (agency for PSG^?)
513-280-0047 or Darren.Wight@deanhouston.com