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Industrial Water Chiller Systems

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Welding Chillers and Heat Management During Welding

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Welding is a common procedure used to join two or more pieces of metal for use in a wide range of applications. The process can be done at outdoor locations (e.g. farms, highways, construction sites) or in an indoor setting, typically shops and factories.

[read: An Introduction to Welding]

Worker Welding

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 reworks

When 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

Collapsed Bridge
(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, process 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.

Cooling During Injection Molding

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Injection molding is a manufacturing process wherein raw materials, most commonly thermoplastic resins in pellet form, are consecutively melted, remolded and cooled. This manufacturing method is typically used in mass-production processes were the same part is being produced thousands or even millions of times in succession. The components made through this process can be found on almost every product that you encounter– from automotive products and electronics to housewares and food packaging.

Weighing plastic particles to be prepped for injection mold

Cooling during Injection Molding

In the injection molding industry, process cooling covers an average 95% of the cycle time. After the end of the first stage of injection, the rest of the molding sequence is cooling. Processors, however, often disregard this critical phase of molding, which can result in a large loss of profit.

While heating and mold cooling are both extremely important during injection molding, cooling is much more critical. It is more difficult to ensure that cooling happens at an even, uniform rate and results in a high-quality product. When cooling is taken seriously and proper cooling tools are in place, manufacturers can reap some impressive benefits.

Benefits of Focusing on Cooling

Save Time and Money

When you have the right tools to heat and cool more quickly, the production process and cycle time can be completed in just a matter of days and requires fewer raw materials. This has the potential to save some serious money, especially on high volume production projects.

[READ: Why Conformal Cooling Makes $ense]

Product Uniformity

Having conformal mold cooling channels allow the coolant to access all part locations evenly. This can reduce the presence of any thermal stress defects such as warpage, sink marks, weld lines, etc.

Colorful plastic blocks

Chemical Consistency

Cooling is vital because the thermoplastic resin doesn’t like to be molten for a long time. If this happens, changes in its chemical make-up will degrade and the plastic might become unusable. Utilizing a high-quality cooling solution will help ensure product integrity.

Scrap Rate Reduction

Efficient cooling reduces scrap rates. Temperature variation is minimized via conventional cooling channels. This helps ensure consistent, reliable, high-quality product.

North Slope Chillers’ injection molding chillers and Fluxwrap fluid channel blankets help you keep your process cooling temperatures under control.

We provide inexpensive and dependable cooling options specifically modeled with our customers’ needs and demands.

Cooling in Printing

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Cooling in Printing

Throughout the printing process heat is generated as a result of friction between component parts and then transferred to ink and paper.  There is also an elevated ambient temperature within the press room. This increased heat can deteriorate the quality of the ink and the overall quality of the printing operation.  Printing chillers and process cooling can preserve and improve print jobs and extend the life of printing equipment.

Moisture is Important

Many outside the printing industry take for granted the fine details and attention required to create the printed materials we read and enjoy every day.  For example, did you know that there is moisture in paper?
Yes, paper is hygroscopic. This means that paper either absorbs or releases moisture to maintain balance with the moisture in the air.  Moisture content is important for inkjet, laser, digital and offset printing, and if unbalanced, it can affect toner adhesion, paper jams, fuser roller temperature, interaction between ink and paper, and ultimately the overall quality of the print job.
Cooling in Printing

Effects of Heat

Because moisture is an important factor in printing, operations are acutely aware of heat. Heat, a natural byproduct of printing, is created by friction and speed in the printing process,  causes moisture in paper or the surrounding air to evaporate, lowering the moisture content. Heat also affects the viscosity of the ink. Ink viscosity increases at lower temperatures, which will slow ink flow and print density. It can also cause mottled print and excessive linting. When temperatures rise, ink lowers in viscosity and over emulsification can occur. Heat can also lead to ink dripping, smearing, misting, or spitting.

Printing Industry Cooling Options

Fans

Some printing operations use fans and air conditioning systems to address heat issues within their facility.  Some large scale printers and are equipped with internal fans to help regulate process cooling in printing.  Due to the unstable chemicals and compounds used, fans are often required to remove and exhaust harmful fumes and odors. Some fans are engineered to work within exhaust systems.

Vent/Exhaust Systems

Another option for removing heat is a vent system.  This works much like a dryer vent in the laundry room.  Heat created in the printing process is forced outside through a vent. Ventilation kits are available for some printers and duplicators. These are exhaust ventilation systems that remove air directly from the machine to an exterior location.

Industrial Chillers

Chillers apply the most direct form of cooling in the printing process.  In the printing industry, industrial chillers remove heat generated by the friction of printing rollers and cool down the paper after it comes out of the ink drying ovens.

As printing machines improve and increase in speed, temperatures of all printing processes become higher. Roller temperature during the press’ start-up phase and in full operation is an important factor to control to protect ink quality.  Chillers are specially designed to regulate temperatures, decreasing print time and improving efficiency.

North Slope Chillers 1/2 ton chiller

A chiller cools process fluids, typically water or a water/glycol mix. These process fluids remove heat from rollers and other component parts, paper, and ink. The fluid absorbs the heat from the printing process and is  then recirculated through the chiller to cool again and again.  Using a chiller in the printing process is a cost effective and reliable method or reducing high temperatures, saving time, and preserving machinery and materials.

DOWNLOAD THE CHILLER SELECTION GUIDE

Determining Chiller Size

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The Perfect Fit

We cannot overstate the importance of selecting a correctly sized chiller. Undersized chillers won’t correctly cool your process equipment or materials. Oversized chillers will work just fine, but why pay more than you need to? When you select a chiller of the proper size, you can rely on several years of efficient cooling. Let’s explore the different parameters one needs to find the perfect chiller size.

Get the chiller selection guide

Tonnage Explained

A Historical Custom

Why are chiller sizes listed according to tons? Well, the answer lies in the cooling practices of yesteryear. Before the age of electronic air conditioners, here in North America especially, blocks of ice were harvested from frozen lakes and rivers and used to cool homes during the summertime. 1 ton of cooling power was the amount of heat transfer needed to melt 1 ton of ice blocks in a 24 hour period. As cooling technology advanced, we began to shift from stored ice to mechanical chilling. In today’s measurements, 1 ton of cooling power = 12,000 btus per hour. Just like we still measure engines according to “horsepower”, the historical practice of using “tons of refrigeration” stuck around.

Pumps and Compressors

A chiller works by using transferring heat between 2 different circuits: the fluid circuit and the refrigeration circuit. The fluid circuit moves unwanted heat into a process fluid, and the refrigeration circuit takes that unwanted heat and disperses it into the ambient air. Both circuits work together continuously to remove excess heat. The fluid circuits uses a pump to keep things flowing, and the refrigeration circuit uses a compressor. The fluid pump and the compressor are the dual engines that keep the chiller running.

Great care is used when selecting the type of pump and compressor used in our chillers. Power, flow rate, efficiency, durability, and noise levels are all taken into consideration for every chiller we offer.

Volts Vs. Amps

Units of electricity can be measured in a few different ways. 2 of the most basic electrical units are used to measure the voltage (volts) and the current (amps). An easy way to understand the difference is to compare electrical flow to water flow. Imagine an electrical wire as a pipe. The voltage (volts) would be the same as measuring the water pressure, and the current (amps) would equal the amount of water in the pipe.

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.

Step One:  Calculate Temperature Differential (ΔT°F)

Step Two:  Calculate BTU/hr.

Step Three:  Calculate tons of cooling capacity

Step Four: Oversize the chiller by 20%

Most likely, your “Ideal Size in Tons” is not going to come out to an even 1 ton, 5 tons, 20 tons, etc. Rounding up will also help you be prepared for any unforeseen heat sources that are present in your setup.

We hope this was helpful! Of course, if you have any questions or would like us to size your chiller for you, please give us a call at (866) 826-2993 or email [email protected]

Chemical Storage: How Should Chemicals Be Stored?

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How should chemicals be stored? Many companies purchase, transport and store chemical drums in warm or hot environments.  Such chemical storage can be problematic as many types of chemicals are adversely affected by exposure to hot temperature environments. Knowing how to store chemicals safely will prevent costly waste and help keep your operation running smoothly.

Warehouse with stacks of totes and drum containers

Harmful Heat During Chemical Storage

All organic chemicals are susceptible to thermal degradation and will oxidize over time and in warm environments. Among the more concerning substances that need to be kept cool are: Paint, coatings, epoxy, scale inhibitors, and corrosion inhibitors. Additionally, some drums containing materials like concrete and specialized chemicals need to be kept cool before they are utilized in a manufacturing process.

So, how can you keep these substances cool during storage?

Refrigerated Rooms

Process cooling solutions can range from simple and easy-to-implement, to difficult and costly. One option is to control the environment that they are stored in. Refrigerated storage rooms can be constructed and small to large amounts of chemical drums can be kept cool at the same time. For very large facilities that store large amounts of chemicals this can be a good, viable solution.

There are some limitations with refrigerated rooms including:

  • Expensive to design and construct
  • Time consuming to set up
  • Difficult to relocate
  • Difficult to scale up if more space is needed
  • Not practical for use if the chemicals are in use at several different points in a facility

Chiller Units: Coils and Blankets

Another option is to provide localized cooling on each drum of chemical. A chemical chiller unit is needed to draw excess heat from the contents of the drum. For the chiller unit to be able to effectively draw off heat a separate heat exchanger is needed to interface the chiller with the drum. There are two types of heat exchangers that can be used: a submersible coil unit or a fluid cooling blanket.

Chemical cooling options diagram

Submersible Coils

A submersible coil unit can be constructed from many types of materials but the two predominant materials used are metal and plastic. The coil is connected directly to a chiller unit and then submerged directly into the chemical drum. The challenges with this approach are:

  • Contamination of the chemicals from coiling unit and airborne debris
  • Localized cooling with a potential of localized freezing
  • Exposure of hazardous chemicals
  • Evaporation of drum contents

Cooling Blankets

A fluid cooling blanket is a heat exchanger that is wrapped around the exterior of a drum. The blanket is connected to a chiller unit and then draws heat off of a drum and maintains a desired temperature. The added benefits of the approach include:

  • Insulation of the drum products
  • Even distribution of cooling medium
  • Containment of hazardous chemicals
  • Reduction in possible contamination of product
  • The ability to cool drums at various points in a facility at the point of use
  • Ability to maintain cool product temperature even in very hot ambient environments

North Slope Chillers

blue portable industrial chiller from North Slope Chillers

North Slope Chillers provide the most innovative and effective chilling systems on the market. They are easy to install and will not disrupt the current setup of your chemical storage. Whether you need to keep materials cool, frozen or anything in between, North Slope Chillers will keep your supplies at the perfect temperature and help prevent costly and time-consuming waste.