The Critical Role and Function of Waterjet Chiller Systems

How Waterjet Chillers Work and Their Importance

Waterjet cutting machines utilize high-pressure water streams to precisely cut a wide variety of materials. The water stream can reach pressures over 90,000 psi and speeds up to Mach 3. At the heart of the waterjet system is an ultra high-pressure pump that pressurizes and delivers a continuous flow of water to the cutting head.

The Role of Waterjet Chillers

A key component that enables these pumps to operate properly is a chiller unit. Waterjet chillers play several crucial roles:

• Cools the hydraulic fluid and oil used to drive the intensifier pump
• Prevents overheating issues that can cause pump failure
• Removes heat from the high-pressure water stream to stabilize pressures
• Allows for superior jet quality and precise, consistent cutting

How Waterjet Chiller Systems Work

Waterjet chillers work similarly to air conditioning units. They utilize a refrigeration cycle to cool and circulate a supply of clean water at the necessary temperature throughout the system.

Here is an overview of the water cooling process:

1. Water is pulled into the chiller unit and passed through a filter to remove solids or debris
2. It enters the evaporator and absorbs heat from the sealed refrigeration system
3. The now cooled water flows into a storage tank or reservoir
4. This chilled water gets pumped to critical waterjet components to absorb excess heat
5. Hot water returns back to the chiller unit where the cooling process repeats

Critical Components of Waterjet Chillers

Waterjet chiller units contain several key components that enable them to continuously cool and circulate water as needed, including:

• Compressor: Compresses and circulates the refrigerant gas through the sealed cooling system
• Condenser: Cools and condenses the compressed gas back into a liquid
• Evaporator: Allows the refrigerant liquid to boil and evaporate, pulling heat from the water
• Expansion valve: Precisely controls the flow of refrigerant liquid entering the evaporator
• Storage reservoir: Holds the chilled water ready for distribution as needed
• Water pump: Maintains the flow of chilled water to key waterjet components

Why Proper Water Chilling is Essential

Maintaining optimal water temperature using a properly sized chiller unit provides multiple benefits including:

• Prevents pump overheating for reliable operation
• Minimizes hydraulic oil and fluid temperatures
• Reduces component wear-and-tear from excessive heat
• Stabilizes waterjet pressure and cutting tolerances
• Maximizes pump and component lifespan
• Enables finer precision cutting

Water Quality Standards for Chiller Units

For proper functioning, waterjet chillers require clean inlet water meeting stringent purity levels. Water standards involve parameters like:

• Total dissolved solids (TDS) – Measurement of inorganic solid matter levels dissolved within the water
• pH levels – Measurement of the water’s relative acidity or alkalinity
• Chloride concentrations – Measurement of dissolved chlorides in the water
• Hardness – Measurement of dissolved calcium and magnesium content

Facility tap water often fails to meet waterjet chiller purity standards. In these cases, additional pretreatment is essential, like reverse osmosis filtration. Keeping inlet water clean preserves system reliability and lifespan.

Specialized Chiller System Designs

While all waterjet chillers share similar functionality, units can be customized to match different machine cutting power levels, environments, and workload requirements:

• Standard chillers – For handling typical machine workloads under normal ambient conditions
• High-temp chillers – Allow reliable operation even in extremely hot environments like foundries
• Low-flow chillers – Maintain proper temperatures even with minimal or intermittent pump usage
• High-powered chillers – Designed for larger systems with 100+ horsepower pumps

When pairing a chiller with a waterjet pump unit, the chiller cooling capacity must match the heat load capabilities of the pump for optimal efficiency.

Other Advanced Chiller Functions

More sophisticated chiller units also incorporate monitoring capabilities and advanced features like:

• Digital displays showing real-time data like water temperatures and cooling load percentages
• Programmable microprocessors handling critical control functions
• Alert notifications when critical parameters fall outside setpoints
• Built-in redundancy via multiple compressors or pumps
• Internet connectivity, remote diagnostics, and data trending

FAQs

What temperature should my chiller cool the water to?

Recommended water temperature from the chiller is between 60-80°F. This chilled water absorbs heat from key components like the high pressure pump, preventing overheating issues.

What water purity is required for chillers?

Waterjet chillers need clean inlet water, usually purified by methods like reverse osmosis. Standard requirements involve less than 30 ppm total dissolved solids, hardness less than 30 ppm, and chlorides under 15 ppm.

How often does my chiller system require maintenance?

Annual chiller maintenance helps maximize performance and lifespan. This involves inspection of parts like pumps, valves, filters, and heat exchangers. Refrigerant levels and water quality should also be checked.

Can my facility tap water be used in the chiller?

Tap water often fails to meet required purity levels for chillers. Pretreatment using methods like reverse osmosis, deionization, or distillation ensures proper water cleanliness to prevent scale buildup or corrosion.