Diaphragm metering pumps are a type of measuring equipment that primarily uses specially designed flexible diaphragms instead of pistons, achieving fluid intake and discharge through the reciprocating motion of the drive mechanism. Their working principle involves altering the pump chamber volume by the reciprocating motion of the diaphragm, thereby completing the transfer of liquid.

Structure and Working Principle

Diaphragm metering pumps are typically composed of an electric motor, transmission system, hydraulic end, and control system. The cylinder components include the pump head, suction valve assembly, discharge valve assembly, diaphragm, and diaphragm base. During operation, the motor drives a worm and worm gear via a coupling to reduce speed, causing the main shaft and eccentric wheel to rotate, which in turn moves the plunger back and forth within a guide tube. In this reciprocating motion, the diaphragm, along with the unidirectional valve, creates a vacuum within the pump chamber, suctioning in fluid; when the diaphragm moves forward, the suction valve closes and the discharge valve opens, expelling the fluid.

Application Scenarios and Industries

Diaphragm metering pumps are widely used in fluid measurement and transfer under various special working conditions, particularly excelling in mediums that are thick, corrosive, flammable, or explosive. Their primary application fields include:

Chemical Industry: Used for conveying various acids, bases, salts, and organic solvents to ensure the progression of chemical reactions.

‌Petroleum Industry: Used for transporting raw materials, catalysts, and additives, ensuring the accuracy of chemical reactions. Additionally, it is also used in processes such as water and steam injection.

Industry: Used for measuring and conveying various drug raw materials and formulations.

‌Food Industry: For measuring and transferring of berries, beverages, and other food products.

Pros and Cons, Maintenance and Care

The advantages of diaphragm metering pumps include:

High Precision: Advanced structural design and the selection of new materials enhance the lifespan of the diaphragm, with excellent corrosion resistance.

High Reliability: The diaphragm's isolation function achieves separation between the measured fluid and the driving lubrication mechanism, eliminating the possibility of contamination and leakage.

Excellent isolation: Effectively prevents leakage, ensuring safety.

In maintenance, diaphragm metering pumps should be regularly inspected for membrane wear and worn membranes should be replaced promptly. Additionally, keeping the pump body clean and preventing contaminants from entering the pump is crucial. Regularly checking and replacing seals and lubricants is also necessary.