Positive Displacement Pumps

A positive displacement pump is a type of pump that moves fluid by trapping a fixed volume of fluid and then forcing it out of the pump. This is in contrast to a centrifugal pump, which moves fluid by imparting kinetic energy to it.

Positive displacement pumps are used in a variety of applications, including:

v  Transferring fluids between tanks

v  Pumping fluids through pipelines

v  Metering fluids

v  Dispensing fluids

v  Generating high pressures

Classification of positive displacement pumps:

Positive displacement pumps can be classified into two main categories: reciprocating pumps and rotary pumps.

• Reciprocating pumps use pistons, plungers, or diaphragms to move the fluid. The piston or plunger moves back and forth in a cylinder, trapping a fixed volume of fluid each time. The fluid is then forced out of the cylinder when the piston or plunger moves back.
• Rotary pumps use rotating gears, vanes, or lobes to move the fluid. The gears, vanes, or lobes trap a fixed volume of fluid as they rotate, and the fluid is then forced out of the pump as they continue to rotate.

Types of positive displacement pumps

There are many different types of positive displacement pumps, each with its own advantages and disadvantages. Some of the most common types of positive displacement pumps include:

• Piston pumps: Piston pumps are the most common type of reciprocating pump. They are used to pump a variety of fluids, including water, oil, and chemicals.
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  Piston pump positive displacement
• Plunger pumps: Plunger pumps are similar to piston pumps, but they use a plunger instead of a piston. Plunger pumps are often used to pump viscous fluids.
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  Plunger pump positive displacement
• Diaphragm pumps: Diaphragm pumps use a flexible diaphragm to move the fluid. Diaphragm pumps are often used to pump hazardous fluids.
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  Diaphragm pump positive displacement
• Gear pumps: Gear pumps use a pair of gears to move the fluid. Gear pumps are often used to pump low-viscosity fluids.
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  Gear pump positive displacement
• Vane pumps: Vane pumps use a rotor with vanes to move the fluid. Vane pumps are often used to pump viscous fluids.
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  Vane pump positive displacement
• Lobe pumps: Lobe pumps use a pair of rotating lobes to move the fluid. Lobe pumps are often used to pump high-viscosity fluids.
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  Lobe pump positive displacement

Uses of positive displacement pumps :

Positive displacement pumps are used in a wide variety of applications, including:

• Water pumping: Positive displacement pumps are often used to pump water for irrigation, drinking water, and fire protection.
• Oil pumping: Positive displacement pumps are used to pump oil for petroleum production, lubrication, and heating.
• Chemical pumping: Positive displacement pumps are used to pump chemicals for industrial processes, such as manufacturing and cleaning.
• Food and beverage processing: Positive displacement pumps are used to pump food and beverage products, such as milk, juice, and soda.
• Medical applications: Positive displacement pumps are used in medical applications, such as intravenous fluid delivery and blood transfusion.

American standards related to positive displacement pumps :

There are a number of American standards related to positive displacement pumps. Some of the most important standards include:

• ANSI/ASME B73.1-2019: Positive Displacement Pumps This standard covers the design, construction, and testing of positive displacement pumps.
• ISO 13708: Positive Displacement Pumps This international standard covers the design, construction, and testing of positive displacement pumps.

Positive displacement pumps are a versatile type of pump that can be used in a wide variety of applications. They are characterized by their ability to move a fixed volume of fluid with each cycle, which makes them well-suited for applications where precise flow control is required.

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