Diaphragm pumps are robust and safe to run dry. These positive displacement pumps are characterized by gentle pumping of low-viscosity to highly viscous and particulate and powdery media. Conventional diaphragm pumps are reliable even with media containing gases. The low-shear operation of the diaphragm pump is particularly ideal for pumping media with fragile or abrasive solids. The easy handling and high operational reliability save time and resources.
Compared to electric diaphragm pumps, pneumatic diaphragm pumps offer additional advantages. They can also be used very easily in ATEX areas without a power supply.
The function of the diaphragm pump is based on the lifting movement of a flexible diaphragm, which is mechanically driven by an eccentric or compressed air. This movement generates suction and pressure cycles. Ball or flap valves on the suction and pressure side control the product flow. On the downward stroke, the diaphragm draws in the medium, while on the opposite cycle it expels it. The continuous change generates a flow rate.
The double diaphragm design results in less pulsation. Pulsation dampers can be used to additionally counteract this and ensure a more even flow rate.
Dosing, conveying, emptying and pumping over
Up to abrasive, corrosive, gaseous and particle-laden media
Chemistry and surface technology
Industry
Waste water, recycling and the environment
Pharmaceuticals, fine chemicals & cosmetics
Construction and transportation
Agriculture and biogas
Dosing, conveying, emptying and pumping over
Up to abrasive, corrosive, gaseous and particle-laden media
FoodPharmaceuticals, fine chemicals & cosmetics
Drinks
Up to abrasive, corrosive, gaseous and particle-laden media
Chemistry and surface technologyIndustryWaste water, recycling and the environmentPharmaceuticals, fine chemicals & cosmeticsConstruction and transportationAgriculture and biogas
Specially developed for feeding chamber filter presses: Dosing, conveying, feeding, feeding
to abrasive, corrosive, gaseous and particle-laden media
Waste water, recycling and the environment
Conveying, emptying and pumping
Powdery media
FoodFine chemicals, pharmaceuticals, cosmetics
Dosing, conveying, emptying and pumping over
Up to abrasive, corrosive, gaseous and particle-laden media
FoodDrinksPharmaceuticals, fine chemicals and cosmeticsChemistry and surface technologyAgriculture and biogasIndustryConstruction and transportationWaste water, recycling and the environmentThe installation of air-operated diaphragm pumps is quicker and easier than with many other pumps. Regardless of whether the pumps are installed with an inlet, as a self-priming variant or as a submerged variant. With a minimum of components and a seal-free design, these pumps are virtually maintenance-free. This reduces downtimes, lowers maintenance costs and ensures high operational reliability in daily use, even with media containing particles. Different material designs enable use in numerous areas of application, so you always get the right solution at attractive conditions for pumping media at low cost. Depending on the requirements, the diaphragm pumps are available with ATEX approval for potentially explosive areas or with food-compliant materials and corresponding certificates for hygienic processes.
Diaphragm pumps are insensitive to abrasive and corrosive media as well as to contamination. They pump solvents and sludges in waste water, recycling and environmental applications just as reliably as they pump paint, acid and alkaline solutions in chemical and surface technology. In industry, latex emulsions, formwork and hydraulic oils are pumped, while fertilizers and pesticides are pumped in agriculture. In the food industry, chocolate and delicatessen products as well as creams, hair gel and latex in the pharmaceutical, fine chemicals and cosmetics industries are among the common pumped media for hygienic stainless steel pumps. These are often also suitable for CIP and SIP
These pumps are always safe to run dry and, thanks to their low-pulsation delivery, high resistance and long service life, they are even used in the construction and transportation sectors for pumping liquids. Even in ATEX zones.
Are you looking for a double diaphragm pump? We offer flexible solutions tailored to your individual application.
The reliable function and low energy consumption of the pump depend to a large extent on the correct design. Specifications for the pumped medium such as temperature, viscosity, density and solids content determine the choice of pump unit and its size, in addition to process data such as flow rate, pressure and operating conditions. The materials used and their surface quality must also be suitable for the respective application. Optional requirements such as explosion protection, necessary certificates or special standards are also crucial. Structured recording of these parameters ensures that the solution is technically suitable, reliable and efficient in the long term.
When integrating a diaphragm pump into an existing system, the focus is on smooth integration into the system. Existing pipelines, connection standards, space conditions and existing drive and control concepts are specifically taken into account in order to minimize adaptation costs and downtimes.
As part of retrofit projects, we replace your existing unit or optimize your pump, for example to improve efficiency, operational reliability or ease of maintenance. A careful analysis of the current situation ensures that the new solution is technically compatible, existing processes continue to run stably and future requirements are taken into account.
We offer you professional design, commissioning and training as well as manufacturer-compliant maintenance. You can also obtain original spare parts, such as diaphragms, valves and O-rings, as well as accessories including documented quality control from our spare parts specialists. On request, we can supply certificates of conformity and material certificates as well as CE documentation. Clear service agreements, fast response times and traceable test protocols create predictability and security for your business.
Rototec supports you throughout the entire life cycle of your pumps, from consultation and design to commissioning and ongoing operation. The aim is a technically sound implementation that focuses on reliability, ease of maintenance, durability and cost-effectiveness right from the start.
We will find the optimum solution for your application.
The air consumption of the pneumatically driven air-operated diaphragm pump is specified in standard cubic meters (Nm³/min). The standard conditions refer to:
Depending on the manufacturer, both oil-free and lubricated air can be used for operation. Tapflo air-operated diaphragm pumps work without lubrication. This not only eliminates the need to constantly check an oiler, but also avoids oil mist in the vicinity of the air-operated diaphragm pumps.
Yes, EHEDG-certified air-operated diaphragm pumps are specially developed for aseptic applications. They enable CIP/SIP cleaning, prevent bacterial growth thanks to their hygienic design and are ideal for sensitive products thanks to their stainless steel housing and gentle pumping.
The purchase price of an air-operated diaphragm pump is considerably lower than that of an electrically driven diaphragm pump. However, the operating costs of an electric diaphragm pump are considerably lower so that, depending on the mode of operation, the investment has already paid for itself after around 3 years compared to the compressed air costs.
The desired delivery pressure can be set using a pressure regulator. The stroke frequency can be set with a needle valve and the flow rate can be continuously adjusted via the air volume. This allows the pump to be operated efficiently and precisely at the operating point.
Air-operated diaphragm pumps build up a strong negative pressure (vacuum). Depending on the pump size, they can draw in up to 5 m dry and 8 m filled.
The correct air pressure is crucial for reliable and efficient pump performance. Too low a pressure reduces the delivery rate and performance, while too high a pressure puts unnecessary strain on the diaphragms and pump parts and shortens their service life. The shortest possible hose for the compressed air supply is always an advantage.
Diaphragm ruptures can be avoided by using optimized diaphragm materials, the correct operating pressure and an adjusted pump speed. Regular maintenance and inspections also help to detect wear at an early stage.
Pipes that are too small or incorrectly sized can cause cavitation and pressure losses. The right pipe size improves the flow of liquid and protects the pump from damage. If the pump speed is too high, the pump chambers may not fill completely. The correct speed setting ensures even and efficient pumping.
The pump often runs too fast or the air pressure is too high. As a result, there is not enough time for the flexible diaphragm to completely fill the pump chambers. If the number of strokes is reduced, normal suction and delivery is often possible again.
Contamination or worn valves can disrupt the flow of fluid. Cleaning or replacing the valves usually restores performance.
By using chemically resistant materials such as stainless steel or PTFE, excellent service lives can be achieved even with aggressive or abrasive media.
Tapflo air-operated diaphragm pump Complete brochure 
