How do double diaphragm pumps work?

Advantages of a double diaphragm pump

The double diaphragm pneumatic pump is a versatile pump for a wide range of fluids. If the production site has a compressed air supply, you have a robust pump ready for operation.

Principle of operation of a double diaphragm pump
A double-diaphragm pump is a positive-displacement pump that uses two flexible diaphragms that move back and forth, creating a temporary chamber that sucks and pumps fluid through the pump. The membranes function as a separation wall between the air and the liquid.

The first shot

The two membranes that are connected by a shaft through the central section where the air distributor is. The purpose of the air distributor is to direct the compressed air to the back of the number one membrane, moving it away from the center section. The number one diaphragm causes a movement that moves the liquid out of the pump. At the same time, the number two membrane performs a suction stroke. The air behind the number two membrane is vented to the atmosphere, causing a vacuum that sucks the liquid to the suction side. The ball valve is moved away from its seat, allowing the fluid to enter the collector.

The second shot

When the number one pressurized membrane has reached the end of its stroke, the air movement is reversed from the number one membrane on the back of the number two membrane by the air distributor. The compressed air pushes the number two membrane away from the central block, so that the number one diaphragm is pulled towards the central block. In pumping chamber number two, the ball of the discharge valve is pushed out of its seat, while in the pumping chamber number one, the opposite occurs. Once the race is over, the air distributor returns to the back of the number one membrane and restarts the cycle.

Where can double diaphragm pumps be used?

Diaphragm pumps are used in many industries. There are a large number of available building materials that can create a large number of configurations to transfer difficult fluids such as:

• Corrosive chemicals
• Volatile solvents
• Viscous and sticky liquids
• Shear-sensitive food products and pharmaceuticals
• Wastewater and abrasive sludge
• Fluids loaded
• Creams, gels and oils
• Explosive products (ATEX)

In addition to the fluid transfer properties, a membrane pump can be specified for ATEX zones, hygiene applications CE 1935/2004, FDA and 3A among other industry compliance measures.

Why air operated pumps?

The is a versatile pump that allows users in various industries to standardize on one type of pump to transfer a wide variety of fluids. If there is an available compressed air supply, the pump can be installed and if the needs change, it can be moved around a plant and used for other operations with ease. The diaphragm pump offers an efficient, low-maintenance solution for fluids requiring delicate pumping as well as chemically and physically aggressive liquids.