A

Absolute Pressure: The total pressure within a system, measured relative to a perfect vacuum.

Absolute Zero: The lowest possible temperature, 0 Kelvin (-273.15°C), where all molecular motion ceases.

Accumulator: A device that stores fluid under pressure for future use in a hydraulic system.

ACFM (Actual Cubic Feet per Minute): The actual volume of gas pumped per minute, measured at the inlet conditions.

Actuator: A device that moves or controls a valve, often powered by air, electricity, or hydraulics.

Adsorbate: A material that takes in gas by adsorption.

Adsorption: The process by which gas molecules adhere to the surface of a solid.

Air Chamber: A chamber filled with air to absorb pressure fluctuations in a pump system.

Air Separator: A device that removes air from the fluid before it enters the pump.

Air-Inlet Valve: A valve used to allow atmospheric air into a vacuum system, also known as a vacuum breaker or vent valve.

Airlock: A condition where air is trapped in the pump or piping system, preventing normal fluid flow.

AIS - American Iron and Steel

Angle Valve: A valve with an inlet and outlet at a 90-degree angle, used to change the direction of flow.

ANSI Pump: A pump that meets the standards set by the American National Standards Institute (ANSI) for chemical process pumps.

ANSI/ASME B73.1: A standard for horizontal end suction centrifugal pumps used in chemical process industries.

Antisuckback Valve: A device that prevents the backflow of oil and air from a vacuum pump into the system when the pump stops.

Atmospheric Pressure: The pressure exerted by the weight of the atmosphere, typically measured as 760 mmHg at sea level.

Axial Flow Pump: A type of pump where the fluid flows parallel to the pump shaft.

Axial Thrust: The force exerted along the axis of the pump shaft, which can affect bearing life and pump performance.

 

 B

BABA – Build American Buy American

Back Pull-Out Design: A pump design that allows the removal of the rotating element without disturbing the piping connections.

Backflow: The reverse flow of fluid in a piping system, which can cause damage or contamination.

Backing Pump: A pump used to maintain the pressure in the foreline of a high-vacuum pump.

Backstreaming: The flow of pump oil or other working fluid back into the vacuum system.

Baffle: A device used to direct or control the flow of fluid within a pump or piping system.

Balance Line: A line that connects the high-pressure side of a pump to the low-pressure side to balance hydraulic forces.

Ball Valve: A valve that uses a spherical ball with a hole through it to control flow, offering quick shutoff.

Base Pressure: The lowest pressure that a vacuum system can achieve without any gas load.

Baseplate: A metal plate on which the pump and motor are mounted to ensure alignment and stability.

Bearing: A component that supports the rotating shaft and reduces friction.

Bellows Pump: A type of positive displacement pump that uses a bellows mechanism to move fluid.

Bellows Seal: A type of mechanical seal that uses a flexible bellows to accommodate shaft movement.

Belt-Drive Pump: A pump driven by a belt connected to a motor, allowing for variable pump speeds.

Bleed Valve: A valve used to remove air or gas from a pump or piping system.

Booster Pump: A pump used to increase the capacity and efficiency of a primary vacuum pump.

Booster Pump: A pump used to increase the pressure of a fluid in a system.

Bubble Point: The pressure at which gas bubbles start to form in a liquid, important for avoiding cavitation.

Butterfly Valve: A valve with a rotating disc to regulate flow, commonly used for large pipe diameters.

Bypass Valve: A valve that allows fluid to flow around a pump or other component to control pressure or flow rate.

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 C

Canned Motor Pump: A pump with a motor enclosed in a hermetically sealed can, eliminating the need for a mechanical seal.

Capture Pump: A type of vacuum pump that removes gas molecules by trapping them on a surface.

Cartridge Pump: A pump design where the entire pumping element can be removed as a single unit for maintenance.

Cartridge Seal: A pre-assembled mechanical seal unit that can be easily installed or replaced.

Casing Wear Ring: A replaceable ring in the pump casing that reduces leakage and wear.

Cavitation: The formation and collapse of vapor bubbles in a fluid, which can cause damage to the pump.

Centrifugal Pump: A type of pump that uses a rotating impeller to increase the velocity of a fluid, converting kinetic energy into pressure energy.

Check Valve: A valve that allows fluid to flow in one direction only, preventing backflow.

Closed Impeller: An impeller with shrouds on both sides to reduce leakage and improve efficiency.

Closed-Coupled Motor: A motor directly connected to the pump without a separate coupling, often used in small pumps.

Closed-Coupled Pump: A pump where the impeller is directly mounted on the motor shaft, eliminating the need for a separate coupling.

Cold Trap: A device used to condense vapors from a vacuum system by cooling them, preventing contamination of the pump.

Compound Mechanical Pump: A pump with multiple stages of compression to achieve higher vacuum levels.

Compression Ratio: The ratio of the outlet pressure to the inlet pressure of a pump for a specific gas.

Conductance: The measure of the capacity of a vacuum system's piping to allow gas flow, typically measured in liters per second.

Control Valve: A valve used to regulate flow, pressure, or temperature in a system, often operated by an actuator.

Critical Flow: The flow rate at which a pump operates most efficiently, often indicated on the pump curve.

Critical Speed: The speed at which a pump's rotating components resonate, potentially causing damage.

Cryogenic Pump: A pump designed to handle extremely low-temperature fluids, such as liquid nitrogen or liquid oxygen.

Cryopump: A vacuum pump that uses cold surfaces to condense and trap gases.

Cutwater: The point in a pump volute where the fluid is directed towards the discharge.

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 D

Degassing Valve: A valve used to remove dissolved gases from a fluid before it enters the pump.

Degassing: The removal of gas and vapors from a substance under vacuum.

Diaphragm Pump: A type of positive displacement pump that uses a diaphragm to move fluid.

Diaphragm Valve: A valve that uses a flexible diaphragm to control flow, suitable for corrosive or viscous fluids.

Diffuser: A component that slows down the fluid flow and increases pressure in a centrifugal pump.

Diffusion Pump: A high-vacuum pump that uses a jet of vapor to direct gas molecules towards the pump outlet.

Direct-Drive Pump: A pump with a motor directly coupled to the pump rotor, providing a fixed pump speed.

Discharge Head: The vertical distance between the pump's centerline and the point of fluid discharge.

Displacement: The geometric volume swept by the pump mechanism per unit time, also known as free air displacement.

Double Mechanical Seal: A mechanical seal arrangement with two seals in series or parallel to provide additional leakage protection.

Double Suction Pump: A centrifugal pump with two suction inlets, designed to balance the hydraulic forces.

Dry Pump: A vacuum pump that operates without any lubricating or sealing fluids.

Dry Running: Operating a pump without fluid, which can cause damage to the pump components.

Dynamic Head: It is the total head that a pump must overcome, including static head and friction losses.

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 E

Efficiency: The ratio of the pump's hydraulic power output to the mechanical power input, expressed as a percentage.

Elastomer: A rubber-like material used in seals and gaskets for flexibility and durability.

Elastomeric Coupling: A flexible coupling made of elastomeric material to absorb shock and vibration.

End Suction Pump: A type of centrifugal pump with the suction inlet on one end and the discharge outlet on the top.

End-of-Curve: The point on a pump's performance curve where it operates at maximum flow and minimum head.

End-of-Life: The point at which a pump or its components are no longer functional or efficient and need replacement.

Exhaust Pressure: The pressure at the outlet of a vacuum pump.

Expansion Joint: A flexible connector used to absorb thermal expansion and contraction in a piping system.

Explosion-Proof Pump: A pump designed to operate safely in hazardous environments where flammable gases or vapors are present.

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 F

Flange: A projecting rim or edge used to connect pipes, valves, or pumps to a piping system.

Flexible Coupling: A coupling accommodating slight misalignment between the pump and the motor.

Flooded Suction: A condition where the pump's suction line is always filled with fluid, ensuring easy priming.

Flow Rate: The volume of fluid that a pump can move in a given amount of time, typically measured in gallons per minute (GPM) or liters per second (L/s).

Flushing: The process of cleaning a pump or piping system by circulating a cleaning fluid through it.

Foreline: The vacuum line connecting the vacuum system to the inlet of a vacuum pump.

Free Air Displacement: The theoretical volume of air a pump can move per unit time, measured at standard conditions.

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 G

Gas Ballast: A feature in some vacuum pumps that allows the introduction of a controlled amount of air to prevent condensation of vapors.

Gate Valve: A valve that uses a flat gate to control flow, providing a straight-through passage when fully open.

Gear Pump: A type of positive displacement pump that uses gears to move fluid.

Getter: A material used to absorb gas molecules in a vacuum system.

Gland Follower: A component that compresses the packing material in a stuffing box to create a seal.

Gland Packing: Material used to seal the space between the pump shaft and the casing, often made of graphite or PTFE.

Gland: A component that compresses packing material to create a seal around the pump shaft.

Globe Valve: A valve with a movable disk and stationary ring seat, used for regulating flow.

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 H

Head: The height at which a pump can raise fluid, often measured in meters or feet.

Helium Leak Detector: An instrument used to detect and measure leaks in a vacuum system using helium as a tracer gas.

Hydraulic Balance: The design feature balances hydraulic forces within a pump to reduce axial thrust.

Hydraulic Efficiency: The ratio of the pump's hydraulic power output to the power input, excluding mechanical losses.

Hydraulic Gradient: The slope of the hydraulic grade line, representing the energy loss due to friction in a piping system.

Hydraulic Institute (HI): An organization that sets standards for pumps and pumping systems.

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 I

Impeller: A rotating component of a centrifugal pump that transfers energy from the motor to the fluid being pumped.

Inducer: A small impeller located at the pump's suction inlet to reduce NPSH requirements and improve suction performance.

Inlet Pressure: The pressure of the fluid entering the pump.

Inlet Velocity: The speed at which fluid enters the pump, affecting NPSH and cavitation risk.

Ion Pump: A type of capture pump that uses an electric field to ionize and trap gas molecules.

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 J

Jet Pump: A pump that uses a jet of fluid to create a vacuum and move another fluid.

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 K

Knudsen Flow: A flow regime in which the mean free path of gas molecules is comparable to the dimensions of the vacuum system.

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 L

Labyrinth Ring: A ring with a series of grooves used to restrict fluid leakage in a pump.

Labyrinth Seal: A non-contacting seal that uses a series of grooves to restrict fluid leakage.

Lantern Ring: A ring placed in the stuffing box of a pump to distribute sealing fluid.

Leak Detector: An instrument used to identify and locate leaks in a vacuum system.

Leak Rate: The rate at which gas enters a vacuum system through leaks, typically measured in torr-liters per second.

Lobe Pump: A type of positive displacement pump that uses lobed rotors to move fluid.

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 M

Magnetic Drive Pump: A pump that uses a magnetic coupling to transfer power to the impeller without a direct mechanical connection.

Mass Spectrometer: An analytical instrument used to measure the mass-to-charge ratio of ions, often used in vacuum systems to analyze gas composition.

Mechanical Booster Pump: A pump used to increase the capacity and efficiency of a primary vacuum pump.

Mechanical Efficiency: The ratio of the pump's mechanical power output to the power input, excluding hydraulic losses.

Mechanical Runout: The amount of deviation or wobble in a rotating pump shaft, which can affect seal performance.

Mechanical Seal: A device used to seal the rotating shaft of a pump to prevent leakage.

Micron: A unit of length equal to one-millionth of a meter, often used to measure vacuum levels.

Molecular Flow: A flow regime in which gas molecules move independently of each other, typically occurring at very low pressures.

Multistage Pump: A pump with multiple impellers to increase pressure in stages.

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 N

Needle Valve: A valve with a small, tapered point to precisely control flow, often used in instrumentation.

Non-Clog Pump: A pump designed to handle solids without clogging, often used in wastewater applications.

Non-Return Valve: Another term for a check valve, which prevents backflow.

NPSH (Net Positive Suction Head): The absolute pressure at the suction port of the pump, critical for avoiding cavitation.

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 O

Open Impeller: An impeller with vanes exposed on one or both sides, allowing solids to pass through more easily.

Open-Coupled Pump: A pump with a separate coupling between the motor and the pump, allowing for easier maintenance.

Orifice Plate: A plate with a hole used to control fluid flow in a piping system.

Outgassing Rate: The rate at which gas is released from materials within a vacuum system.

Outgassing: The release of gas from materials within a vacuum system.

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 P

Packing Gland: A component that holds the packing material in place and compresses it to create a seal.

Packing: Material used to seal the space between the pump shaft and the casing.

Partial Pressure: The pressure exerted by a single component of a gas mixture.

Peristaltic Pump: A type of positive displacement pump that moves fluid through a flexible tube by compressing it.

Pirani Gauge: A type of thermal conductivity gauge used to measure low vacuum pressures.

Piston Pump: A type of positive displacement pump that uses a piston to move fluid.

Plug Valve: A valve with a cylindrical or conical plug to control flow, offering quick operation.

Positive Displacement Pump: A pump that moves fluid by trapping a fixed amount and forcing (displacing) that trapped volume into the discharge pipe.

Pressure Gauge: An instrument used to measure the pressure of fluid in a pump or piping system.

Pressure Relief Valve: A valve that opens to release excess pressure in a pump or piping system to prevent damage.

Priming Chamber: A chamber in a self-priming pump that holds fluid to assist in priming.

Priming: The process of removing air from the pump and suction line to allow the pump to function properly.

Pump Curve: A graph showing the relationship between a pump's flow rate and head, used to determine its performance.

Pump Jack: A device used to lift and lower the pump for maintenance or inspection.

Pumping Speed: The volume of gas a vacuum pump can remove per unit time, typically measured in liters per second (L/s).

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 R

Radial Bearing: A bearing that supports the pump shaft and resists radial forces.

Radial Flow Pump: A type of centrifugal pump where the fluid flows perpendicular to the pump shaft.

Radial Thrust: The force exerted perpendicular to the axis of the pump shaft, affecting bearing life and pump performance.

Reciprocating Pump: A type of positive displacement pump that uses a back-and-forth motion to move fluid.

Regenerative Pump: A type of vacuum pump that uses a rotating impeller to create a vacuum.

Rotary Piston Pump: A type of positive displacement pump that uses a rotating piston to create a vacuum.

Rotary Vane Pump: A type of positive displacement pump that uses rotating vanes to create a vacuum.

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 S

Scroll Pump: A type of dry pump that uses two interleaved spiral scrolls to compress and move gas.

Seal Chamber: The area in a pump where the mechanical seal is located.

Seal Flush: A system that circulates clean fluid to the mechanical seal to prevent contamination and cooling.

Seal: A device used to prevent leakage of fluid from the pump.

Self-Priming Pump: A pump designed to remove air from the suction line and prime itself.

Shaft Alignment: The process of aligning the pump shaft with the motor shaft to ensure smooth operation.

Shaft Runout: The amount of deviation or wobble in a rotating pump shaft, which can affect seal performance.

Shaft Seal: A seal that prevents fluid from leaking along the pump shaft.

Shaft Sleeve: A protective sleeve that fits over the pump shaft to prevent wear and corrosion.

Slurry Pump: A pump designed to handle abrasive or viscous fluids containing solid particles.

Solenoid Valve: An electrically operated valve that uses a solenoid to control flow, commonly used in automation.

Sorption Pump: A vacuum pump that removes gas by adsorption or absorption.

Sorption: The process of gas molecules being absorbed or adsorbed by a material.

Sputter Ion Pump: A type of ion pump that uses sputtering to remove gas molecules from a vacuum system.

Stuffing Box: A chamber in a pump where packing material is placed to create a seal around the shaft.

Submersible Pump: A pump designed to operate while fully submerged in the fluid it is pumping.

Suction Bell: A bell-shaped component at the pump's suction inlet that helps direct fluid into the impeller.

Suction Lift: The vertical distance between the fluid source and the pump's centerline.

Suction Strainer: A filter placed at the pump's suction inlet to remove debris and prevent clogging.

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 T

Thermal Desorption: The release of adsorbed gas molecules from a surface by heating.

Thermal Relief Valve: A valve that opens to release excess pressure caused by thermal expansion in a pump or piping system.

Thermocouple Gauge: A gauge that measures vacuum pressure based on the thermal conductivity of gases.

Three-Way Valve: A valve with three ports, used to divert flow between two different paths.

Throttle Valve: A valve used to control the flow rate by varying the size of the flow passage.

Throughput: The amount of gas a vacuum system can process per unit time.

Thrust Bearing: A bearing that supports the pump shaft and resists axial forces.

Thrust Collar: A component that supports the pump shaft and resists axial forces.

Torr: A unit of pressure equal to 1/760th of an atmosphere, commonly used in vacuum measurements.

Trap: A device used to capture contaminants or vapors before they reach the vacuum pump.

Turbine Pump: A type of centrifugal pump with multiple stages and a high head.

Turbomolecular Pump: A high-vacuum pump that uses rapidly rotating blades to direct gas molecules towards the pump outlet.

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 U

Ultimate Pressure: The lowest pressure that a vacuum pump can achieve.

Ultimate Vacuum: The lowest pressure that a vacuum pump or system can achieve under ideal conditions.

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 V

Vacuum Chamber: A sealed enclosure from which air and other gases are removed to create a vacuum.

Vacuum Gauge: An instrument used to measure the pressure within a vacuum system.

Vacuum Valve: A valve designed to control the flow of gases in a vacuum system.

Valve Seat: The surface against which the valve disk or plug seals to stop flow.

Valve Stem: The rod that connects the actuator or handle to the valve disk or plug, transmitting motion.

Vane Pump: A type of positive displacement pump that uses vanes mounted on a rotor to move fluid.

Vapor Diffusion Pump: A type of diffusion pump that uses a vapor jet to create a vacuum.

Vapor Lock: A condition where vapor bubbles form in the pump or piping system, preventing normal fluid flow.

Vapor Pressure: The pressure at which a fluid will vaporize at a given temperature, important for avoiding cavitation.

Vapor Pressure: The pressure exerted by a vapor in equilibrium with its liquid or solid phase.

Vavles

Viscosity: A measure of a fluid's resistance to flow, affecting pump performance and efficiency.

Viscous Flow: A flow regime in which gas molecules interact frequently, typically occurring at higher pressures.

Viscous Fluid: A fluid with high resistance to flow, affecting pump performance and efficiency.

Volumetric Efficiency: The ratio of the actual volume of fluid pumped to the theoretical volume the pump should move.

Volute: A spiral-shaped casing of a centrifugal pump that converts kinetic energy into pressure energy.

Vortex Pump: A pump that uses a vortex created by an impeller to move fluid.

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 W

Wafer Valve: A type of butterfly valve that fits between two flanges, held in place by bolts.

Water Ring Pump: A type of vacuum pump that uses water as the working fluid to create a vacuum.

Wear Plate: A replaceable plate that protects the pump casing from wear caused by abrasive fluids.

Wear Ring: A replaceable ring that reduces leakage between the impeller and the pump casing.

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 Y

Y-Strainer: A device used to remove debris from the flow, protecting valves and other equipment.

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 Z

Zero Leakage Pump: A pump designed to operate without any fluid leakage, often used in hazardous or toxic applications.