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2023-12-27 How to Select the Most Efficient Diaphragm for Your Wilden® AODD Pump
You can’t have air-operated double-diaphragm (AODD) pumps without the diaphragms. After all, it’s part of the name—and the design. But diaphragms are more than just components that fit inside your AODD pump.

Diaphragms help ensure the safe, efficient and cost-effective operation of your AODD pumps and contribute to extending pump lifespan, but only if you select diaphragms that suit your specific application, whether for wastewater, paints, food products, acids or any other substance.

However, selecting the right diaphragm can be challenging, especially since various diaphragm material options are available and every application requires unique performance characteristics.

Fortunately, Wilden® makes choosing the best diaphragm for your AODD pump simple. Let’s look at the factors you should consider when choosing the most efficient diaphragm for your AODD pump.

The Seven Factors to Consider When Selecting AODD Diaphragms
While operator expertise and familiarity with diaphragms offer a simple approach to diaphragm selection, even the most experienced operator should consider multiple factors before making their choice. After all, there is no one-size-fits-all diaphragm for every application.

To identify the ideal diaphragm for a specific application, the following seven key factors should be taken into account: abrasion resistance, chemical resistance, temperature ranges, adherence to sanitary standards, inlet condition, longevity and cost.

Abrasion resistance refers to how well the diaphragm can endure wear and friction caused by solids and particles present in the fluid being processed.

Chemical resistance evaluates how well the material of the diaphragm aligns with the characteristics of the processed fluid.

Temperature ranges encompass the diaphragm's adaptability and effectiveness across different temperature levels, including its performance under extremely high and low-temperature conditions.

Sanitary standards are particularly relevant for diaphragms utilized in food, beverage, and pharmaceutical settings, ensuring the diaphragm aligns with hygienic and sanitary requirements.

Inlet condition assesses a diaphragm's capability to transfer fluid between different locations.

Longevity, also referred to as flex life, represents the projected lifespan of the diaphragm before it needs replacement.

Cost involves various factors, including the initial price, anticipated application lifespan, costs incurred during downtime, and expenses associated with diaphragm replacement labor.
Now that we know what to consider when selecting a diaphragm, we can examine the three primary materials used for diaphragms.

The Three Primary AODD Diaphragm Materials
AODD pumps use three primary materials – rubber, thermoplastic elastomer (TPE), and polytetrafluoroethylene (PTFE). Each of these materials offers specific attributes that are well-suited for different applications.

Rubber AODD diaphragms are created using synthetic rubber along with a nylon fabric mesh to enhance their flexibility. There are four types of rubber diaphragm materials: neoprene, Buna-N, EPDM, and FKM.

Neoprene is a versatile, cost-effective diaphragm intended for nonaggressive chemical applications, like water-based slurries and seawater. It is known for its longevity and abrasion resistance.

Buna-N is most effective when used with petroleum- and oil-based liquids, ranging from gasoline to turpentine. Also known as nitrile, this diaphragm offers moderate longevity and abrasion resistance, ideal for food and beverage applications.

EPDM serves as a low-cost alternative diaphragm when pumping diluted acids or caustics in food, pharmaceuticals, manufacturing, and paint and coatings applications. It is recognized for their good longevity and moderate resistance to abrasion.

FKM diaphragms are engineered to handle extremely high temperatures and aggressive chemicals like aromatic and chlorinated hydrocarbons. They possess a moderate level of longevity and abrasion resistance.
TPE AODD pump diaphragms are manufactured using injection molding, eliminating the need for fabric reinforcement seen in their rubber counterparts. These diaphragms offer four material choices: polyurethane, Wil-Flex®, Saniflex™ and Geolast®.

Polyurethane is a versatile diaphragm suitable for nonaggressive chemical applications like water and wastewater, demonstrating outstanding longevity and abrasion resistance.

Wil-Flex, a cost-effective alternative to PTFE, is ideally designed to handle corrosive fluids like sodium hydroxide and hydrochloric acid in chemicals, pharmaceuticals and wastewater applications, offering excellent longevity and abrasion resistance.

Saniflex, made of Hytrel®, offers low compression set characteristics, good longevity and excellent abrasion resistance, making it ideal for food processing applications.

Geolast, similar to (Buna-N or Buna-TPE), is most commonly used in petroleum applications due to its extreme oil resistance and low oil swell. It Offers moderate longevity and good resistance to abrasion.
PTFE can be used with a wide range of fluids, even highly-aggressive variations like hydrocarbons, acids, caustics, ketones and acetates, offering excellent longevity and moderate abrasion resistance in pharmaceutical and food and beverage applications.

However, PTFE is non-elastic, so a backup diaphragm made of different materials is required for memory and flexibility. Neoprene, Saniflex and high-temperature Buna-N are ideal backup diaphragm options.

The Diaphragm Selection Guide
To optimize the performance of your AODD pump, you should carefully choose the most suitable diaphragm for your specific application—and selecting the right diaphragm means carefully identifying and considering multiple factors and application requirements.

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2023-10-30 Best Bond PEVA Duct Support Job reference
Best Bond PEVA British Standard Class 'O' Duct Support At No.21 Choi Hung Road

2023-06-29 Wilden® Minimizes Product Recalls With Saniflo™ Hygienic™ Series AODD Pumps
From a delicious home-cooked meal to a relaxing glass of wine, food and beverages provide the nutrients and satisfaction that are essential to life. That’s why food and beverage operations are tasked with following strict health regulations to help ensure a variety of products remain safe for human consumption. However, food and beverage processors are faced with many challenges, including product recalls and loss from contamination.
“Manufacturers are doing everything possible to avoid product recalls or losses,” says Tom Zuckett, Americans Northeast regional sales manager for PSG®. “That’s why we’ve designed our Wilden® Saniflo™ Hygienic™ Series Air-Operated Double-Diaphragm (AODD) Pumps to be highly cleanable and drainable.”
One–Of–A–Kind Design
Saniflo Hygienic Series Diaphragm Pumps are designed for the high-cleanliness requirements of food and beverage applications. The flow-through liquid-path design eliminates any potential areas where residue can become trapped. At the same time, the free-draining flow path provides quick and easy draining without needing to disassemble the pump, allowing for clean-in-place (CIP) capability. This state-of-the-art design helps simplify cleaning and ensures high cleanliness, further reducing contamination risk, costs and downtime. In fact, the Saniflo Hygienic Series is the only US-manufactured AODD pump in the industry to have 3A certifications for CIP operations.
“Additionally, when equipped with Wilden Pure-Fuse Integral Piston Diaphragm (IPD) technology, the common bacteria trap in standard diaphragms is eliminated,” Zuckett says. “Pure-Fuse diaphragms are also much easier to clean between product changeovers and have a much longer service life. Because the diaphragm doesn’t hold back fluids, bacteria traps are eliminated.”
The AODD pumps also help in production environments commonly manned by new operators, Zuckett points out. “These operators have fewer skills, so air-operated systems are easier for them; they’re more forgiving,” he says.
Energy efficiency is also a factor for Saniflo Hygienic Series pumps thanks to the Wilden Pro-Flo SHIFT air distribution system (ADS). The design of the Pro-Flo SHIFT optimizes the Saniflo Hygienic Series’ performance by lowering air and energy consumption, increasing productivity, minimizing maintenance and reducing compressed air costs by up to 60%.
The responsibility that comes with handling products intended for human consumption is challenging. For this reason, food and beverage operations need simple, reliable and energy-efficient Saniflo Hygienic Series Pumps to help operations provide the food and beverages people enjoy and need by minimizing the risk of product recalls and loss due to contamination.

2011-06-30 Caterpillar Hong Kong has upgraded a 25 year old dyno from 2,500 to 3,000 HP
An over 25 years old Power Test dynamometer used by the Caterpillar Hong Kong has been upgraded from 2,500 to 3,000 HP.

Proven dependability and durability of this dynamometer has been achieved from the durability of the parts that were engineered more than 30 years ago and are proven thru their years of reliable performance.

We assist customer with parts fitment because there have been minor changes over the years thru manufacturer's drive to continually improve its product. This dyno, although built over 25 years ago as a manually controlled dyno, can be easily upgraded to enjoy all automated controls and data acquisition of Power Test modern day standards because dyno absorber is relatively unchanged.

This 25 years old dyno has been completed the upgrading and continues its servicing in June this summer.

2010-01-13 CLP Black Point Power Station
After the sucessful modification for the two air intake chambers of the gas turbine gensets for the CLP Power at the Black Point Power Station in Hong Kong, Freudenberg's Compact Pocket Filter T 60 has gained approval and trusted by the station's management team. The T 60's outstanding performance was proved by our client after a 14 month continously operation without replacement. As advised, a filter replacement had to carried out every three to four months before our modification. The modification has already shown a big return of money by no filter replacement and less air pressure differential during the last 14 months. Therefore, higher power output and no loss of power during filter replacement is acheived.

For more details, please contact Edmond Yan

2009-06-30 Hong Kong Government Dockyard has Hong Kong's most advanced diesel engine testing and exhaust gas analyzing system
The Government Fleet Division (GFD) manages and maintains the Government Dockyard (GD) which serves as a maintenance base for about 795 operational vessels of different types and sizes, of which about 116 are major mechanised vessels and about 75 are speed boats. Over 45 mechanized vessels are used as marine transport or special tasks by various government departments and these vessels use GD as the operational base and are provided with operational crew by Marine Department.

Planned and unplanned Maintenance of government vessels are performed regularly and repairs are carried out as and when necessary, about 90 % of which are performed by private contractors and remaining 10 % by in-house skill staff of GD. The Maintenance Section in GD monitors the work done by the contractors and ensures the work is completed in accordance with the job specifications.

In 2008 fall, GD had decided to upgrade its existing Power Test dynamometer with manual data acquisition system to meet and fulfill the current standard for diesel engine testing and contacted Power Test, Inc. USA for assistance. As the local partner of Power Test, Inc. in Hong Kong and China, we successfully completed the modification, installation, commissioning and on-site operational training (both theory and hands-on trainings inclusive) for the GD in 2009 summer. The new system is the most advanced integral diesel engine testing and computerized data acquisition and control with exhaust gas analyzing system in Hong Kong.

The new system includes:

1. One unit of modified Power Test 25X08 Dynamometer
2. One set of new titanium plate type heat exchanger for sea water cooling
3. One set of new Power Test Dynamic Fuel Measurement System
4. One set of new Power Test PowernetLT Data Acquisition and Control System
5. One set of new Lancom-III 9-Gas Emission Analyzer System

For detail project information, please contact Edmond Yan at