Welding requires the following components: metals to be joined, a heat source, and a filler metal. The most common types of welding found in industrial environments are: Gas Tungsten Arc Welding (GTAW), Stick Welding, Gas Metal Arc Welding (GMAW), and Flux Core Arc Welding. [read: 4 Popular Types of Welding Procedures]

​It may go without saying, but high-quality welding requires careful heating/temperature management. Temperature management before, during and after welding defines the preciseness and quality of the weld.

Here are a few reasons why we’re careful about temperature control when it comes to welding:
It can prevent some costly and time-consuming reworksWhen working on common materials like cast irons, copper (and its alloys) aluminum, and steels, proper heat dispersion and management prevents stress and weakened metals. Quick changes in temperature can mean extra work if not wasted materials. Take it from us: any time saved by cutting corners on heat control will only come back to haunt you. It’s better to take your time with temperature to maintain the integrity of your materials and product.

It reduces the risk of Hydrogen Induced Cracking (HIC)Hydrogen Induced cracking, is “caused by the blistering of a metal due to a high concentration of hydrogen.” Carefully approaching the heating and cooling of welded materials allows hydrogen to be properly drawn out. This effectively reduces or eliminates the risk of HIC and, consequently, expensive and time-consuming reworks (see above).


It relieves residual stress(THE SILVER BRIDGE IN OHIO, 1967, BELIEVED TO HAVE COLLAPSED DUE TO RESIDUAL STRESS FROM UNEVEN COOLING)

In welding, the quick thermal expansion and reduction created along a very limited spot could become a major source of residual stress. This is stress that remains within an object/material after the external source of stress has been removed. While residual stress may be desirable in some engineering applications, uncontrolled residual stress should be avoided at all costs. This uncontrolled, undesirable stress leads to weak welds and premature structural failure.

Residual stress frequently occurs when a welded metal’s temperatures are raised and quickly lowered with little or no control or when cooling occurs unevenly. Slowly and carefully removing heat from welded materials prevents the welded spot from becoming too fragile and ductile.


At North Slope Chillers, we’re all about taking the stress out of welding temperature control (pun intended). Our products provide controlled, even cooling that will help maintain the strength and integrity of your welded products. Additionally, we offer custom solutions– whatever your cooling needs are, we can help!
Give us a call at (866) 826-2993 if you’re interested in incorporating a chiller into your welding process.

The Formula
Regardless of what you are cooling, this formula will determine your needed chiller size. Before jumping in, identify the following variables:

• Incoming water temperature
• Required chilled water temperature
• Flow rate

To illustrate how this formula works, let’s say we need to cool 4 GPM (gallons per minute) from 85 °F to 75 °F. This makes our incoming water temperature 85 °F, the required chilled water temperature 75 °F and the flow rate 4 GPM.

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The refrigeration circuit is the most technical part of how a chiller works.The refrigeration cycle uses the principles of thermodynamics to efficiently move heat from one area to another. In the case of chillers, heat is taken from the fluid being chilled and transferred to the ambient air.


1. The Compressor
The refrigeration cycle begins with the compressor. The compressor takes low-pressure low-temperature refrigerant in gas form and compresses it into a high-pressure high-temperature gas.


2. The Condenser
This gas then flows through coils in the condenser. While in the condenser, air or water will flow over the coils and remove heat from the refrigerant. As the refrigerant loses heat it will begin to condense until all of the gas has condensed into a liquid.


3. The Expansion Valve
After leaving the condenser, the liquid goes through the expansion valve. The expansion valve restricts the flow of refrigerant. When the high-pressure liquid goes through the expansion valve it enters the evaporator.


4. The Evaporator
The evaporator is where the refrigerant starts evaporating back into a gas. When the refrigerant evaporates it gets very cold and absorbs a lot of heat. It is in the evaporator that the process fluid will interact with the cold refrigerant. Heat is removed from the fluid and transferred to the refrigerant. The refrigerant will then enter the compressor and the cycle begins again.

​Now that you know how a chiller works, you may be considering your chiller system options. North Slope Chillers boast the most advanced active refrigeration circuit available. They are easy to install, remove and relocate and will not disrupt the layout of your current system. Whether you’re looking to cool, freeze, or anything in between, North Slope offers a solution to meet your needs.

Additional resources
https://www.thermalcare.com/how-does-a-chiller-work/
https://en.wikipedia.org/wiki/Chiller

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