Pumping high viscosity liquids9/17/2023 ![]() ![]() ![]() Figure 2.211 shows an example of speeds used for gear pumps with internal gears. ![]() As a rule the speed of the pump is reduced in inverse proportion to the viscosity raised to about 0,7. In principle the speed should be chosen in inverse proportion to the viscosity, but this results in too high a purchase cost for the pump. At high viscosities the speed of the displacement pump must be reduced. Pumping high viscosity liquids with positive displacement pumps there are some considerations to make. This feature is the reason for AODD pump’s capabilities to pump high-viscosity products.Displacement pumps for highly viscous Iiquids Typically, a dry suction lift of up to four meters is possible and can get up to 8.2 meters when the pump is being used in a flooded application. The fact that AODD pumps can be dead-headed is handy when transferring product to filling heads.ĪODD pumps do not require positive inlet pressure to prime, such as flooding or a dry suction lift. Opening the valve causes a pressure drop in the delivery line for the pump to resume operating. The pump will stop when the liquid pressure in the delivery line reaches the same pressure as the driving air fueling the pump’s action. In an AODD pump, a valve fitted into the delivery line can stop the flow of liquid. This continual recirculation raises the temperature and can damage and reduce pump life. Other pump technologies can incorporate special controls or circulation loops to enable dead heading the pump.ĭead heading can occur when, for example, a discharge valve in a centrifugal pump is closed or blocked, causing the flow of liquids to cease or the same fluids to recirculate. This feature proves beneficial during pump priming or forĬertain types of pumps must be protected against dead-heading to avoid damage or breakage and an expensive replacement. Running dry can shorten a pump’s service life if not engineered for that capability. can be easily cleaned-in-place (CIP)/sanitizedĪODD pumps can run dry without damage to internal parts, a feature common to only three pump styles-diaphragm, piston and peristaltic.can manage solids and pump high-viscosity products.An AODD pump is a type of positive displacement pump without a seal, supplying it with a set of features including:.It also supplies effective transfer of high-viscosity sludges and slurries or fluids with abrasive materials. Known for its gentle movement, AODD pumps work well with shear. The positive pressure forces it out of the discharge. Negative pressure pulls liquid to one side and The air pressure within the pump drives the pair of diaphragms in a repeated back-and-forth motion to create positive and negative pressures in the wet pump. Within an AODD pump, two flexible diaphragms, powered either by gas or compressed air, alternately fill and then discharge two chambers. A positive displacement pump continually cycles in and then discharges a set volume of material/fluids from its inlet to its discharge valve. These can maintain a consistent flow rate even under pressure variations. Mechanics Driving an AODD PumpĪn AODD pump is a type of positive displacement pump. Examining the AODD pump and its features/benefits can help determine if this style best suits application parameters. With numerous pump styles that serve various purposes, selecting the right style and size of pump can improve production efficiencies, increase plant safety and reduce unnecessary downtime. Industries including pharmaceuticals, food and beverage, mining, pulp and paper, paints and coatings and wastewater, rely on AODD pumps to safely and effectively move liquids of varying viscosities, such as dangerous or potentially hazardous fluids. Air-operated double diaphragm (AODD) pumps are found in up to 90% of the manufacturing and operating facilities in the United States, according to some estimates. ![]()
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |