China Pumping Solutions Leader
Pneumatic diaphragm pump is commonly used in industry positive displacement reciprocating pump, wide range of application, convenient use and maintenance, better experience than gear pump, but there are still some users reflect the use of diaphragm pump effect did not meet expectations, the use of diaphragm pump accessories easy to damage and other problems. The reason for these problems is not only the purchase of low-quality products, but also part of the original selection of the most suitable model. Choose a suitable diaphragm pump for working conditions, the main consideration is to consider the material, flow, suction, head, particle size, temperature, viscosity and other factors, the following answers for everyone.
Air-Operated Double Diaphragm Pump Datasheet
| Model | Inlet/Outlet (INCH） | Max.Capacity （GPM/LPM） | Max.Head （M） | Outlet pressure (BAR) | Air inlet (INCH) |
| SKQ-10 | 3/8″ (10 mm) | 5.8/22 | 70 | 7 | 1/4 |
| SKQ-15 | 1/2″ (15 mm) | 5.8/22 | 70 | 7 | 1/4 |
| SKQ-20 | 3/4″ (20 mm) | 15/57 | 70 | 7 | 1/4 |
| SKQ-25 | 1″ ( 25 mm) | 15/57 | 70 | 7 | 1/4 |
| SKQ-25A | 1″ (25 mm) | 31/116 | 84 | 8.4 | 1/2 |
| SKQ-32 | 1.2″ (32 mm) | 40/151 | 84 | 8.4 | 1/2 |
| SKQ-40 | 1.5″ (40 mm) | 40/151 | 84 | 8.4 | 1/2 |
| SKQ-40A | 1.5″ (40 mm) | 100/378.5 | 84 | 8.4 | 1/2 |
| SKQ-50 | 2″ (50 mm) | 100/378.5 | 84 | 8.4 | 1/2 |
| SKQ-65 | 2.5″ (65 mm) | 100/378.5 | 84 | 8.4 | 1/2 |
| SKQ-50A | 2″ (50 mm) | 150/568 | 84 | 8.4 | 1/2 |
| SKQ-80 | 3″ (80 mm) | 150/568 | 84 | 8.4 | 1/2 |
| SKQ-100 | 4″ (100 mm) | 150/568 | 84 | 8.4 | 1/2 |
| SKQ-80A | 3″ (80 mm) | 275/1041 | 84 | 8.4 | 3/4 |
| SKQ-125 | 5″ (125 mm) | 275/1041 | 84 | 8.4 | 3/4 |
1. First of all, to determine the material of the diaphragm pump, the common pump body material is: cast steel, cast iron, aluminum alloy, stainless steel (304/316/316L), plastic PP polypropylene, fluorine plastic (PVDF), PTFE, according to the nature of the material to choose. Non-corrosive materials generally choose cast iron, ductile iron or aluminum alloy material, corrosive liquid according to the degree of corrosion, choose stainless steel, plastic or fluorine plastic material. Please refer to the corrosion parameter table of the material. In the case of uncertain material characteristics, it is recommended to choose the same material as the pipeline. If the material temperature is high, it is recommended to use stainless steel and perfluorine diaphragm pump. If the material with hard particles, it is recommended to use metal diaphragm pump. After selecting the material of the pump body, the vulnerable flow parts of the diaphragm pump should be selected, which is also crucial to the use experience. The vulnerable flow parts of the diaphragm pump refer to the diaphragm, ball and ball seat. The material is divided into three channels, Teflon, polyether, super Teflon, etc., which should be selected according to the corrosion, wear and temperature of the material.
2 Determine the model size of the diaphragm pump, according to the flow or caliber to choose. The flow rate marked by the pneumatic diaphragm pump refers to the water test value under the drive of 7 kg stable compressed air, under the condition of 0 suction and 0 head. The actual flow rate should be estimated according to the working condition (suction and head will affect the flow rate, can refer to the flow curve or ask the manufacturer to determine). Try to choose the flow and pipe diameter matching diaphragm pump, but if the caliber and flow do not match the case, can also be installed in the inlet and outlet diameter joint (diameter will affect the diaphragm life and flow, so the diameter range should not be too large). Pneumatic diaphragm pump belongs to the positive displacement pump, the shear of the material is low, can transport the material with particles, but the size of the transported particles must be less than the maximum diameter of the pump can pass through the particles, too large particles need to be filtered before pumping.
3. Pneumatic diaphragm pump can transport the viscous material below 10000 centipoise, but the transport of more viscous material, should choose a larger than the required flow diaphragm pump, because the flow data of pneumatic diaphragm pump is calculated by water test, viscous material resistance will make the flow smaller
4. When using diaphragm pump to transport food or pharmaceutical materials with high hygiene level requirements, sanitary pneumatic diaphragm pump should be selected from stainless steel. Because the inner and outer walls of the sanitary pneumatic diaphragm pump are polished by mirror, there is no dead point, and it is easy to disassemble and clean. The ordinary pneumatic diaphragm pump can not meet the requirements of the sanitary level from the design