QBY-25 Pneumatic Diaphragm Pump, Stainless Steel Diaphragm Pump

Specifications and Parameters ：

Product Overview：

The QBY pneumatic diaphragm pump is a new type of conveying machinery and currently the most innovative pump category in China. Utilizing compressed air from an air compressor as its power source, it can thoroughly extract and suction various corrosive liquids, liquids containing particles, as well as high-viscosity, volatile, flammable, and highly toxic liquids. Available in eight diameter specifications: ￠10mm (3/8“), ￠15mm (1/2”), ￠25mm (1“), ￠40mm (1 1/2”), ￠50mm (2“), ￠65mm (2 1/2”), ￠80mm (3“), ￠100mm (4”). Three materials: aluminum alloy, cast iron, stainless steel.

Pneumatic diaphragm pumps utilize different rubber diaphragms—Nitrile rubber, Neoprene rubber, Fluororubber, or PTFE—tailored to various liquid media, meeting diverse user requirements. Since production commenced, these pumps have been adopted by over a thousand domestic enterprises across petroleum, chemical, electronics, ceramics, textiles, paint, and pharmaceutical machinery sectors. Installed in specialized environments, they efficiently handle media unsuitable for conventional pumps.

Product Features：

The QBY pneumatic diaphragm pump is a positive displacement pump that operates by the reciprocating deformation of a diaphragm to create volume changes. Its working principle is similar to that of a plunger pump. Due to the characteristics of its operating mechanism, the pneumatic diaphragm pump possesses the following features:

(1) No overheating: Compressed air serves as the power source. During exhaust, it undergoes an expansion and heat absorption process. Consequently, the temperature of the pneumatic pump decreases during operation, and no harmful gases are emitted.

(2) No electrical sparks: Pneumatic diaphragm pumps operate without electricity. Grounding prevents static sparks.

(3) Capable of handling liquids containing particles: The positive displacement design and ball valve inlet minimize clogging.

(4) Extremely low shear force on materials: Fluid is discharged exactly as it is drawn in, minimizing agitation and making it suitable for transporting unstable substances.

(5) Flow rate is adjustable: A throttle valve can be installed at the outlet to regulate flow.

(6) Features self-priming capability.

(7) Can run dry without risk.

(8) Capable of submersible operation.

(9) Capable of handling an extremely wide range of fluids, from low-viscosity to high-viscosity, and from corrosive to viscous.

(10) No complex control systems; no cables, fuses, etc.

(11) Compact size and lightweight for easy mobility.

(12) No lubrication required, simplifying maintenance and preventing dripping contamination of the work environment.

(13) Maintains consistent high efficiency without degradation from wear.

(14) Achieves 100% energy utilization; automatically shuts off when outlet is closed, preventing equipment movement, wear, overload, or overheating.

(15) Eliminates dynamic seals for easy maintenance and leak prevention. Operates without dead spots.

Product Application：

1. Pumping peanut butter, kimchi, mashed potatoes, small sausages, jam, apple puree, chocolate, etc.

2. Pumping paint, resin, pigments.

3. Adhesives and glues—all types can be pumped.

4. Glaze slurry for various tiles, ceramics, bricks, and pottery.

  5. Pumping sediment and grout after oil well drilling.

6. Pumping various emulsions and fillers.

7. Pumping all types of sewage.

8. Pumping sewage from oil tankers and barges during hold cleaning.

9. Pumping hop slurry, yeast slurry, syrups, and molasses.

10. Pumping accumulated water from mines, tunnels, shafts, ore processing plants, and slag heaps. Pumping cement grout and mortar.

11. Various rubber slurries.

12. Various abrasives, corrosives, petroleum products, mud, cleaning oil residues, and general containers.

13. Various highly toxic, flammable, and volatile liquids.

14. Strong acids, strong alkalis, and highly corrosive liquids.

15. High-temperature liquids up to 150°C.

16. As a pre-pressurization device for various solid-liquid separation equipment.

Product Working Principle：

Each of the pump's two symmetrical working chambers, A and B, contains a diaphragm. These diaphragms are connected as a single unit by a central connecting rod. Compressed air enters the distribution valve through the pump's inlet port. The distribution mechanism directs the compressed air into one chamber, driving the diaphragm within that chamber to move while expelling the gas from the other chamber. Upon reaching the end of the stroke, the distribution mechanism automatically directs compressed air into the opposite working chamber, driving the diaphragm in the opposite direction. This enables continuous, synchronized reciprocating motion of both diaphragms.

In the illustration, compressed air enters the distribution valve via port E, causing the diaphragm to move rightward. The suction force in chamber A draws the medium through inlet C, pushing ball valve 2 into chamber A while ball valve 4 locks shut due to suction. The medium in chamber B is compressed, forcing ball valve 3 open to discharge through outlet D while simultaneously locking ball valve 1 to prevent backflow. This cyclic operation continuously draws medium into inlet C and discharges it through outlet D.

Repair and Maintenance：

1. When disassembling and reassembling the pump, keep the surfaces of moving components clean to prevent damage from dust, foreign objects, or other contaminants.

2. Before disassembling the pump, drain all liquid from the piping. Prior to disassembly, invert the pump to completely empty any residual liquid inside.

3. If fluid leaks from the exhaust silencer, inspect the diaphragm for damage or check if the diaphragm retaining screws are loose.