The Saniflo Air Operated Double Diaphragm pump lines by Wilden are designed for sanitary applications and are built to be durable, reliable, and versatile. Wilden is known for their customization options; this lets you perfectly tune the AODD pumps to your facility. We selected several standard configurations for our website, but countless other variations are available by special order. All the options can be overwhelming, let's break them down.
Selecting a Sani-Flo Pump Line
We offer two pump lines by Wilden, the Saniflo Hygienic and the Saniflo FDA. Both pumps are designed for sanitary settings and meet FDA and ATEX requirements.
The difference? The Saniflo Hygienic pump is a high clean pump; it has a free-draining flow path removing contamination risks. Certain configurations can meet 3-A Standards and are fully CIP compatible.
The Hygienic pump is often used in the dairy and meat industries for high protein products such as milk, eggs, gravy, and cheese. It is also used for many skin care and cosmetic applications. The FDA Saniflo pump is seen in the food, beverage, and cosmetic industries for products that are high in sugar, acid, salt, fat, and alcohol.
Selecting an AODD Size
Things to consider when sizing a pump
- Size of current piping
- Desired flow rate
- Viscosity of product/ if any partial solids in the product
All Saniflo AODD pumps have Tri-Clamp ends and are able to seamlessly fit into sanitary production lines. We recommend you start by choosing a pump with connections the same as your current system and size up if that pump does not meet the desired flow rate or meet the needs of the product being pumped.
Wilden's Air Intake Systems
Wilden Saniflo pumps are available with two different air intake systems Pro-Flo and Pro-Flo SHIFT. We have chosen to only offer the Pro-Flo SHIFT on our online store, but the Pro-Flo is available by special order if desired. Why have we done this? The Pro-Flo SHIFT has the same base technology as the Pro-Flo but has an added air control spool and two air control valves instead of one, preventing overfilling of the air chambers. The Pro-Flo SHIFT saves air, energy, and money, making it one of the most efficient AODD pumps available.
AODD Air Chamber & Center Block Material
We generally recommend that you select one material for the air chamber, center block, and air valve. If you have a specialty application that requires different materials for these three components, please contact our sales team. These components are not in direct contact with the product but should still be compatible with the product being pumped in case of leaks, spills, and fumes.
The available materials are:
- Aluminum
- Nickel-Plated Aluminum
- Stainless Steel
Aluminum is the least expensive option; however, aluminum is also the most susceptible to abrasive materials and corrosion. Aluminum is recommended for standard applications that do not require chemical resistance.
Nickel-Plated Aluminum has more resistance to abrasive materials and corrosion when compared to aluminum. Nickel-plated aluminum is the mid-tier option and is for applications that require slightly higher resistance than aluminum but not the durability of stainless steel.
Stainless Steel is the most expensive option and has the highest resistance to abrasion and corrosion. Stainless steel is also easier to clean. We recommend stainless steel for higher intensity applications, harsh environments, and acidic, abrasive, or corrosive products.
AODD Diaphragms
Diaphragm Styles
When selecting a diaphragm style you should consider how often it will be maintenanced, whether it needs to be high-clean, and its compatibility with the product being pumped.
Integral Piston Diaphragm
The Integral-Piston diaphragm (IPD) has no outer piston; instead, the piston is integrated into the diaphragm. This removes the dead space that occurs in outer piston designs, reducing the risk of product entrapment and contamination and increasing the sanitation level and the resistance to abrasive products. IPDs have greater flow rates, durability, and flex life when compared to other diaphragms. IPDs are faster to clean and are CIP compatible in the Hygienic 3-A model. The IPD reduces risks or leaks, as the outer piston is a common potential leak point. Wilden's IPD design does not use any adhesives and has a smooth, contoured shape. The IPD is the perfect diaphragm for high clean applications where sanitation is of the utmost importance. For sanitary applications, the pure-fuse IPD is CIP compatible, meets FDA and 3-A requirements, while being less expensive with higher suction life and flow rates than competitors.
EZ-Install Diaphragm
The EZ-Install TPE Diaphragm is designed to be easy to use, install, clean, and maintenance. They can easily replace traditional diaphragms as they have the same footprint. Traditional diaphragms need to be inverted when installed, which is difficult to do, time consuming, and can cause injuries. The EZ-install diaphragm has a convoluted shape that does not need to be inverted. The EZ-Install has the same durability, hardware, and performance as traditional diaphragms, but without the difficult installation process. The EZ-Install diaphragm is available in Wil-Flex and Saniflex.
Traditional Diaphragm
Wilden does offer traditional Pie Shaped Diaphragms. The traditional diaphragm is available in both rubber and TPE. This is the diaphragm style seen across industries that AODD pumps are known for.
PTFE Diaphragm
The PTFE is designed for applications that require high chemical resistance and peak performance. The PTFE diaphragm has a specialized contoured shape and an exceptionally smooth surface but is still compatible with the hardware used with Wilden's traditional diaphragms. The PTFE diaphragm is available in two designs, full-stroke and reduced stroke. The PTFE diaphragm is a high-end option that is perfect for intense applications that require peak performance and high chemical resistance.
The full-stroke is the standard PTFE diaphragm; it is an efficient diaphragm that provides enhanced suction lift and flow rates. This diaphragm is durable, chemically inert, and incredibly reliable. The full-stroke PTFE diaphragm has 2.4 times the displacement stroke when compared to traditional diaphragms.
The reduced-stroke diaphragm has a shortened stroke, lowering efficiency and displacement but allowing for higher abrasion resistance and an exceptional flex life. This diaphragm is only for specialized applications, and we recommend contacting our team directly if you think it is right for you.
Diaphragm Materials
When selecting your diaphragm material, you should consider the temperature range and material compatibility with your product.
TPE
TPE stands for thermoplastic elastomers; they are a plastic-rubber hybrid designed to be flexible and durable, while remaining easy to process. TPEs are injection molded, keeping them affordable without compromising the quality. TPE diaphragms do not require any reinforcement as they have inherent tensile strength. There are two sanitary TPEs available: Wil-Flex and Saniflex.
Wil-Flex is designed for applications involving acidic and caustic products. It was designed by Wilden and shares properties with Santoprene. Wil-Flex is known for its durability, abrasion andchemical resistance, and high flex life.
Saniflex is recommended for food applications, as it is compatible with oils and fats. It can maintain high sealing even with lubricious and low-specific gravity products. Saniflex has good flex life and amazing abrasion resistance and durability.
Rubber
EPDM is the only sanitary rubber diaphragm currently available. It is a commonly found material in sanitary processing industries. EPDM is known for its flexibility, affordability, durability, and wide temperature range. It can handle dilute acids and caustics but is not appropriate for oily products. The rubber diaphragms are reinforced with integral nylon fabric mesh to give them extended durability and flex-life.
PTFE
PTFE is chemically inert and is designed specifically to handle aggressive chemicals. PTFE is the right choice for highly aggressive applications. PTFE is a more expensive material, but it has one of the highest ranges of product compatibility, including aromatic or chlorinated hydrocarbons, caustics, ketones, aldehydes, and acetates. PTFE has good abrasion resistance and durability, and amazing flex life. PTFE diaphragms do require a backup diaphragm, which is available in Wil-Flex, EPDM, and Saniflex.
Technical Specifications
Temperature |
Flex Life |
Abrasion Resistance |
|
Wil-Flex |
-50 ° to 130° C -58° to 266°F |
Great |
Great |
Saniflex |
-29° to 104°C -20° to 220°F |
Good |
Great |
PTFE |
4° to 104°C 40° to 220°F |
Great |
Good |
EPDM |
-51° to 138°C -60° to 280° F |
Good |
Average |
Chemical Resistance/ Applications
Ketones & Aldehydes |
Acetates |
Aromatic Hydrocarbons |
Chlorinated Hydrocarbons |
Oil & Gas |
|
Wil-Flex |
Yes |
Yes |
No |
No |
No |
Saniflex |
No |
No |
Yes |
No |
Yes |
PTFE |
Yes |
Yes |
Yes |
Yes |
Yes |
EPDM |
Yes |
Yes |
No |
No |
No |
AODD Valve Options
Valve Style
The Saniflo FDA pump has standard ball valves, whereas the Saniflo Hygienic has three valve options: ball valves, mushroom valves, and flap valves. Ball valves are the standard option, and the other two are available by special order.
Ball Valves are the standard option; it is available in a variety of materials, provides good suction capability, and is 3-A approved for the Saniflo Hygienic pump.
Mushroom Valves are a specialty valve designed specifically for high viscosity products.
Flap Valves are another specialty valve. Their unique design allows for large solids to pass without restriction.
Valve Materials
We generally recommend that you select the same valve material as your diaphragm as your diaphragm material should already be compatible with your pumped medium. Valves for the FDA pump are also available in stainless steel with PTFE gaskets; this is recommended for applications that require high resistance to chemicals and abrasion. Stainless steel check balls are also heavier, making them suitable for viscous products as they gravity seat faster than TPE or rubber check balls.
AODD Pump Accessories
The Saniflo Hygienic pump line has two available accessories: the swivel stand and the Wil-Gard protection.
Swivel Stand
The swivel stand is a stainless-steel stand that allows the pump to rotate from side to side to ensure that the pump is fully drained. This stand is required for CIP compatibility and 3-A certification.
Wil-Gard III
The Wil-Gard is a diaphragm monitoring system that detects leaks. The sensors of the Wil-Gard alert are positioned at the primary diaphragm and alert when they come into contact with conductive liquids. Wil-Gard leak detection is required for 3-A certification.
Do you require CIP Compatibility or 3A certification?
CIP Compatibility
The Saniflo Hygienic AODD pump is fully CIP compatible, however the swivel stand accessory is required to ensure that the pump fully drains. The free-draining flow path prevents liquid from being trapped in the pump, and the swivel stand allows the pump to be gently rotated to fully empty the pump.
3A Certification
Certain configurations of the Saniflo Hygienic pump are 3-A certified.
Components require for 3-A certification:
- Swivel stand
- IPD Diaphragm
- Wil-Gard protection
If you ever need help customizing your Wilden AODD pump please contact our sales team. Wilden pumps can be designed to fit specific applications, and we are happy to help youu select the correct pump to meet all your needs.