HOW AODD pumps and diaphragm pumps are used in very many industries?

Diaphragm Pumps are common industrial pumps which use positive displacement to move liquids. These devices typically include a single diaphragm & chamber, as well as suction & discharge check valves to prevent backflow. Pistons are either paired to the diaphragm or used to force hydraulic oil to drive the diaphragm. Diaphragm pump is highly reliable because they do not include internal parts that rub against each other. In fact, prolonged diaphragm pumps life may be possible if the diaphragm pump is run dry to prime. Diaphragm pumps have a great capacity to deal with a wide range of material that includes abrasive materials, acids, chemicals, concrete or grout, coolants, combustible or corrosive materials, effluents, groundwater, & gasoline or diesel fuel. AODD pump or diaphragm pumps use the reciprocating action of elastomeric diaphragms & ball valves to pump a fluid. There are many combinations of elastomers & wetted parts – & the fluid to be pumped would define the specific pump to be used. Depending on the flow rate required & the height to which the fluid is to be pumped, the size of the pump should be selected.

How does it work?

An air-valve system is used to move the diaphragm rod. Flexible diaphragms are attached at the end of the diaphragm rod. The pilot spool is pushed back & forth whenever the diaphragm rod reaches the end of its throw. This action allows air to move the air distribution valve back & forth. The air distribution rod controls air flow to the left or right air chamber, reversing on each stroke. The four ball valves are operated by pressure differences in the pumped liquid.

Types of fluids can be pumped & why?

The double diaphragm pump is very versatile pumps & are used in the transfer of highly viscous, abrasive, semi-solid, & shear sensitive materials. These pumps are self-priming hence operation is easy. It is very easy to service with fewer moving parts.

Corrosive/abrasive fluids: can be pumped by selecting the wetted parts & elastomers to withstand the types of fluid to be transferred – the pumps are available in various materials such as Aluminum, Stainless steel (withstand abrasive) & Plastics (withstand corrosive) with elastomers like Viton, Buna N, Santoprene to name a few.

Flammable fluids: Fluids like Acetone, Benzene, Petroleum etc. that easily catch fire, are possible to be pumped because air operated double diaphragm pump is air driven & hence they are inherently safe for use in explosive atmospheres. However, some fluid liquids generate a static charge, so the pumps should be completely grounded. However, it is recommended that one should use certified pumps for such applications.

Highly Viscous Fluids: Viscosity is the resistance to flow. In simple language, we can say it the stickiness of the fluid. Depending on the viscosity of the fluid, the pump size needs to be determined – The higher the viscosity, the larger should the suction & discharge pipe size be. Due to higher frictional losses in the pipeline for high viscosity of liquid fluids, the discharge pressure will be high.

Shear Sensitive Liquids like shampoos, milk & paint when subject to shear (or churning) – whilst being transferred – can result in a change of the product characteristics. Since AODD pump run at lower speed & hence gently move the liquid, they are ideal for use in the transfer of such liquids.

Vapour Pressure: to pump Liquids such as diesel, hydrocarbons which have a low vapor pressure, we need to use a pump that runs at low speed with a limited suction lift to ensure the pump delivers the required flow.

Thus we see that AODD pumps or diaphragm pumps are extremely important in industry & one should make sure one gets the right pump for the job. Click here to know more about aodd pump manufacturer.