Many industrial machines or processes create tremendous amounts of excess heat which must be removed in order to keep operating temperatures at the ideal level. Failure
to adequately remove the heat can result in equipment malfunctions or interruptions to the process that can be costly. The most efficient way to cool equipment is to use an
integrated chiller or cooler that is hooked directly to the heat-generating equipment.
How Chillers and Coolers Work
Chillers and coolers are, generally, not designed for a specific application but rather are engineered to provide stable cooling over common temperature ranges.
Chillers and coolers typically consist of a bath with an integral pump, refrigeration system, temperature controller, and heat exchanger. The equipment to be cooled is attached
to the cooler / chiller via hoses (typically, equipment that must be cooled has integral coils and plumbing to allow for a cooler / chiller to be attached). Coolant flows from
the bath to the machinery where it absorbs excess heat and flows back to the bath which the temperature controller keeps at a constant temperature. Excess heat is carried away
from the bath via a heat exchanger.
Chillers and coolers are classified as either liquid-liquid cooled or liquid-air cooled. Liquid-liquid cooling uses the facility's water supply to carry away the excess heat.
Liquid-air cooling uses a fan blowing across the heat exchanger to remove the excess heat. The ambient air temperature (for liquid-air cooling) or ambient water temperature
(for liquid-liquid cooling) will affect the unit's cooling capacity.
Beyond the cooling capacity, and air versus liquid cooled, one area in which chillers / coolers differ from among each other is the type of pump used to circulate the coolant.
- Turbine pumps are reliable and provide moderate flow and moderate pressures making them well suited to applications that require higher pressure or
experience a higher system pressure drop, such as long tubing runs or pumping vertically. They are also forgiving to impurities in the fluid stream.
- Positive displacement pumps have performance capabilities similar to those of turbine pumps while being suitable for high viscosity fluids. They
produce moderate flow at high pressure making them able to pump higher or further from the cooler to the application.
- Centrifugal pumps offer higher relative flow rates at lower pressures and are most suitable for applications that are either close to the chiller
or require lower pressure. Centrifugal pumps are very quiet and require little maintenance, but they are more sensitive to pressure drops.
Applications for Chillers and Coolers
Chillers and coolers are capable of being integrated into a wide range of applications. Any process that generates excessive heat which must be removed can benefit from a chiller or cooler.
Some common applications include:
Anodizing: An electrochemical process used to improve corrosion and wear resistance of metals requires cooling to keep solvents at the proper temperature.
Calibration: The accuracy and stability of chillers and coolers makes them excellent choices for low temperature calibration standards.
Chemical Processing: The process of combining chemicals or chemical compounds always creates heat. Cooling is needed to ensure that the process and follow-up
testing are done accurately.
Medical testing: Some diagnostic medical equipment such as CT and PET scans and MRIs add large heat loads which requires adequate cooling to prevent the equipment
from overheating and malfunctioning.
Condenser Cooling: Condensers are heat exchange systems that condense substances from their gaseous to liquid states. Chillers and coolers provide an excellent
means of removing latent heat.
Injection Molding: Process by which plastics granules are compressed in a mold through heat and pressure to form an end piece. Rapidly cooling the mold solidifies
melted plastic allowing it to be released.
Laminating: The process of lamination involves uniting two or more layers of material together, using a combination of heat, pressure, and adhesive. Efficiently
applying cooling can reduce downtime and speed up the lamination process.
Lasers: Emit highly amplified and coherent radiation used for precision cutting, etching, and printing. Chillers are used to reduce and control the internal
temperature of the solid state components.
Machine Tool: Friction created from tooling metals causes heat to build up in the recirculated cutting oil. By controlling fluid temperature, greater accuracy
can be achieved because thermal expansions and contractions of the material are eliminated.
Plasma Cutting: Used to cut steel and other metals, by forming an electrical arc through a stream of high speed, inert gas which turns gas into plasma. The plasma
is hot enough to melt or cut the metal. Cooling is needed to maintain tolerances.
Things to Consider When Purchasing a Chiller or Cooler:
- Heat load
- Fluid operating temperature range and set-point
- Cooling capacity
- Ambient temperature
- Temperature stability and accuracy
- External application (open or closed-loop determines pump type)
- Reservoir size
- Pump pressure and/or flow rate External probe/programmability
If you have any questions regarding chillers or coolers please don't hesitate to speak with one of our engineers by e-mailing us at sales@instrumart.com or calling 1-800-884-4967.