Definitions
Fluid Properties and Performance Measures
We have compiled a glossary of definitions for fluid properties and performance measures below. These are terms and acronyms frequently used throughout the Fraser Technologies website. These definitions have been designed as simple one sentence descriptions which may clarify some of the technical terms used on our website. However please don’t hesitate to contact us if you have any questions, which you feel are not answered sufficiently well.
A mixture of two or more liquids that boils as if it were a single substance, so its composition stays constant during use and recovery.
When a blended solvent gradually changes composition during use because its components evaporate at different rates -causing inconsistent performance. Find out more here: Chemical Drift
The temperature at which a liquid turns to vapour; low-boiling-point fluids dry parts quickly and save energy.
The lowest temperature at which a liquid’s vapour can ignite in air; ‘non-flammable’ fluids have no flash point under normal use.
A liquid’s resistance to spreading; low surface tension lets a fluid penetrate tight gaps, fine features and blind holes.
How thick or thin a fluid flows; low viscosity helps a solvent move quickly through complex geometries.
An electrically insulating fluid used to cool or test high-voltage equipment without conducting electricity.
A property that indicates how well a fluid resists conducting electricity, important for immersion cooling of live electronics.
The voltage at which an insulating fluid fails and allows electrical current to pass; higher is better for high-voltage applications.
A fluid used to move heat away from equipment (e.g. semiconductor tools, battery packs) to keep it operating at a safe temperature.
Single-phase keeps the fluid liquid; two-phase uses boiling and condensing to absorb and release much more heat.
The ability of a solvent to retain the same chemical makeup after repeated heating, cooling and recovery cycles.
How effectively a fluid dissolves soils, often expressed in Kauri-Butanol (KB) value; higher KB = more aggressive cleaning.
An additive in older chlorinated solvents that prevented acid formation; modern HFO fluids are inherently stable and need no stabiliser.
A new fluid that can be used in existing equipment with little or no modification, minimising the cost of switching.
A unit of concentration used for workplace exposure limits; the higher the safe ppm, the less hazardous the fluid is to operators.
The maximum concentration of a substance an operator can be exposed to over a working day, set by health and safety authorities.
The information set forth herein is furnished free of charge and based on technical data that Fraser Technologies believes to be reliable. It is intended for use by persons having technical skill, at their own risk. Since conditions of use are outside our control, we make no warranties, expressed or implied and assume no liability in connection with any use of this information. Nothing herein is to be taken as a license to operate under, or a recommendation to infringe any patents or patent applications.
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