(ID) Inside diameter: ID refers to the inside diameter of a cylindrical or tubular component, such as a pipe or tube.

Impeller: An impeller is a device that is attached to a rotating shaft and is responsible for converting the energy of motion into the fluid being pumped. It imparts kinetic energy and generates flow within the fluid.

Impeller eye: The impeller eye is the central opening of an impeller, through which the fluid enters. It is the point where the fluid is initially drawn into the impeller.

Impeller eye diameter: The impeller eye diameter refers to the measurement of the opening or diameter at the impeller eye, which determines the size of the inlet for the fluid entering the impeller.

Impeller locating ring: A locating ring is a concentric ring placed around the shaft to prevent the impeller from moving axially. It ensures that the impeller is positioned correctly on the shaft.

Impeller nut: An impeller nut is a fastener typically in a threaded and hexagonal shape. It is used to secure the impeller to the shaft in overhung pumps, providing a reliable connection.

Impeller setting: Impeller setting refers to the adjustment of the clearance between the impeller and the volute or back pump plate in open impellers. This clearance is typically set after the pump reaches its normal operating temperature and may need to be readjusted over time due to wear.

Impeller shroud: The impeller shroud consists of plates located on either side of the impeller vanes. It serves to protect the impeller from damage by preventing solids or debris from entering the impeller.

Impeller vane: Impeller vanes are mechanical components of the impeller that direct the flow of liquid from the impeller eye to the discharge. They are located at the outer diameter of the impeller and play a crucial role in determining the pump’s performance.

Impeller vane pass frequency: The impeller vane pass frequency is calculated by multiplying the number of vanes on an impeller by its rotational speed. For example, if an impeller has five vanes and rotates at 3560 rpm, the impeller vane pass frequency would be 17,800.

Implode: Implosion refers to the opposite of explosion. In the context of pumps, it occurs when bubbles or cavities within the fluid collapse or implode when subjected to higher-pressure regions. This implosion can generate noise and cause damage to the pump’s internal components. It is commonly known as cavitation.

Inboard: Inboard refers to the relative position of components within a pump. It indicates components that are closer to the pump coupling or the center of the pump. The term “inboard side” or “inboard end” is also used to describe this orientation.

Inclusion: An inclusion refers to a non-metallic contaminating particle or piece of material that becomes embedded within the metal during its manufacturing process. Inclusions can affect the material’s properties and integrity.

Incremental balancing: Incremental balancing involves balancing a rotor in stages by adding no more than two major components at a time. This method allows for more manageable balancing adjustments and ensures better overall balance.

Inducer: An inducer is a small axial vane that is attached to the impeller. Its purpose is to reduce the Net Positive Suction Head (NPSH) required by the pump, allowing for improved pump performance and preventing cavitation.

Induction motor: An induction motor, also known as an asynchronous motor, is an AC motor where current is induced in the rotor by a magnetic field generated by the stator through the process of electromagnetic induction.

Inline pump: An inline pump is a pump that is directly mounted within a fluid flow system without the need for a separate mounting or base plate. It is a compact design that simplifies installation.

Inside mounted seal: An inside mounted seal is a type of mechanical seal in which all the seal components are mounted within the process fluid, providing direct contact with the fluid being sealed.

Intergranular corrosion: Intergranular corrosion is a type of corrosion that occurs between the crystals or grains of a metal, where the corrosion is more likely to happen at the grain boundaries rather than within the grains themselves.

Internal gear pump: An internal gear pump is a type of pump that uses gears to displace the process fluid. The gears are housed in a casing with minimal clearance. One gear faces the inlet, while the other faces the outlet. The rotation of the gears traps and moves the liquid from the inlet to the outlet. Internal gear pumps differ from external gear pumps in that they use a rotor (large ring gear) and an idler (small gear) that face internally.

Internal recirculation: Internal recirculation refers to the loss of efficiency in a centrifugal pump caused by small eddies and recirculating currents within the pump. These internal flows reduce the overall performance and effectiveness of the pump.

IOS: IOS stands for International Standards Organization. It is an organization that establishes pump and seal standards for the industry. The ISO 9000 standard, which focuses on quality management, is one of the well-known standards defined by the IOS.

Iteration: Iteration refers to the process of repeating a set of operations or calculations to approach a desired goal or target. It is often used in mathematical and computational methods to find approximate solutions or to converge towards a specific outcome. Modern computer algorithms heavily rely on iteration to perform complex tasks effectively and efficiently.

Related Links

• Pump Glossary
• Pump info