PureAire Oxygen Analyzer for 3D Printers: How Argon is used and Why O2 Detection is Required

Thanks to new technologies, the 3D printers that have been used to create plastic three-dimensional objects can now print metal. Titanium 3D printing is possible thanks to a technique called DMLS, or Direct Metal Laser Sintering. While the potential to use titanium 3D printing is groundbreaking for many industries, the new advances could pose a health hazard if volatile gases used in the printing process are not contained. Learn more about the role of argon in 3D printing and how an oxygen analyzer can safeguard your employing while printing. 

What Happens in Direct Metal Laser Sintering? 

3D printing of plastics uses an additive process in which objects are constructed layer by layer or fused together cross section by cross section. These basic techniques need rethinking for titanium 3D printing. With Direct Metal Laser Sintering, a laser follows a computer-aided design (CAD) file to melt titanium powder, rendering the object. The process is similar to sculpture, in which pieces of the raw material are carved away to create or reveal a three-dimensional object or figure. 

Because titanium is such a strong metal, the resulting objects are highly durable. For something like medical devices or three-dimensional replacement joints or bones, this means that individuals can get greater use out of the replacement part. Aviation professionals greet these new developments, estimating that titanium parts can cut the weight of an airplane by as much as 1,000 pounds, saving fuel on every flight. 

Since the titanium powder (Or other metal powders) used in this additive manufacturing process is created from manufacturing remnants, the materials are highly cost-effective. 

What are the Risks of 3D Printing? 

The 3D printer operates in an inert environment, where argon prevents any unwanted chemical reactions from taking place and maintains the purity of components. The inert environment in the 3D printing machine keeps the oxygen content low, to reduce oxidization in the manufactured part. It also reduces the fire hazard by rendering combustible dust inert. Since thermal stress is controlled and titanium powder clumping is reduced, the argon improves the consistency of the final product and reduces deformities. 

While there are many benefits to using argon in the printing process, and argon is harmless when contained, it does pose a health risk should the argon escape the additive manufacturing environment. 

Argon is known as an oxygen displacer. This means that when argon gas leaks into the air, it physically displaces the levels of oxygen in the air. In extreme cases, staff can asphyxiate due to the lack of oxygen in the environment. 

This gas is colorless, tasteless, and odorless. Were argon to leak out of the 3D printer, staff would be unable to see or smell it. As soon as oxygen begins to deplete from the room, it cause symptoms including dizziness, shortness of breath, and confusion. Even if staff suspect that something is wrong, they may be unable to escape from the area before it is too late. 

When you have a poorly ventilated manufacturing space with several 3D printers going at once, the potential for oxygen displacement by argon gas increases.

How Can an O₂ Analyzer Reduce Risks? 

An O₂ Analyzer helps keep levels inside the 3D printing environment low, to ensure the printer works optimally. Without the analyzer, there would be no way to ensure that the ppm concentration of oxygen remained at a steady state for the duration of the printing process. The oxygen analyzer checks levels of oxygen ranging from 0 to 1,000 parts per million (ppm). 3D printers using the DMLS process need to keep the oxygen under 1% or less for product manufacturing. A 0 to 25% oxygen range detector is also available. The oxygen analyzer can make sure that the air inside the chamber meets the low levels needed. Meanwhile the air outside is safe for staff to breath. PureAire's oxygen analyzers are easy to install and easy to use. Once set up, they require no maintenance and will work as promised for a set period of time.

At PureAire, we have just developed a new oxygen analyzer that works with 3D printers. To learn more about our new oxygen analyzer, please visit www.pureairemonitoring.com or send an email to info@pureaire.net. 

Source

http://nj.gov/health/eoh/rtkweb/documents/fs/0151.pdf

http://3d-printing-titanium.com/titanium-3d-printer-everything-you-need-to-know/

Air Separation Plants and the Use of Oxygen Monitors

Air separation plants are critical for many different industries, from clean energy to manufacturing. Nowadays, cryogenic is the most common type of distillation used to separate air into its component gases - nitrogen, oxygen, and inert gases including helium and argon. If your industry relies on air separation for product development or manufacturing, then knowing how the process works is an important part of operational safety. Learn about air separation plant operation and safety protocol to be informed. 

How Air Separation Plants Work

In the cryogenic air separation process, air is chilled to the liquid stage. At this point, nitrogen and oxygen can be separated out from the inert gases in the air. Each compound can then be distilled at boiling temperature, thereby returning the liquid to a vapor state. The resulting nitrogen and oxygen gases are highly pure. 
To get the air ready to be separated, plant employees first filter the air to remove particles, such as dust. Next, the air is pressurized and then filtered up to several times to remove carbon dioxide, which can freeze the distilling equipment. 

Using a still and heat exchanger, workers heat and cool the gas, turning it into a highly pure liquid. The oxygen liquefies and falls to the bottom, while the highly pure nitrogen gas floats above the oxygen since it is lighter. 
Once separated, the gases can be kept in gaseous state or returned to a liquid state via chilling. Many air separation plants have elaborate pipe systems, whereby the oxygen or nitrogen gas can be transported directly to production lines. 

Air separation plants have many diverse uses. Pure oxygen gas is a basic component of metalwork including steel manufacturing. Nitrogen gas helps preserve edible oils from oxidizing and is used as a safeguard against combustion in shipping and cargo transit. 

The cryogenic process is effective and efficient at separating air; however, it does pose some safety risks. Air is safe to breathe when nitrogen and oxygen are together in the appropriate ratio. As nitrogen and oxygen are separated two distinct hazards emerge. 

Pure oxygen increases the fire danger in an environment. If not controlled, this could turn dangerous. 
Pure nitrogen depletes oxygen and can cause death via asphyxiation. Since nitrogen is colorless and odorless, workers may not know if the distilled nitrogen has escaped the still and infiltrated the environment. Argon acts in a similar manner, yet is a less common hazard since it is present in trace levels in oxygen. 
Without a safeguard of an oxygen monitor, staff may be exposed to toxic gases. In a worst-case scenario, staff could die. 

How an Oxygen Monitor Protects Staff

Between 1992 and 2002, 80 workers died from nitrogen exposure. Workers may fall unconscious after even a single breath of oxygen deficient air. If individuals do not receive oxygen in a matter of minutes, the consequences are grave. 

Educating staff about the dangers of these gases is a first step toward operational safety. Installing an oxygen or O₂ monitor is the next step to keeping everyone safe. 

An O₂ monitor measures the levels of oxygen in the air at any given time. The device takes sample readings of the air and remains silent as long as there is sufficient oxygen in the environment. Since argon and nitrogen deplete oxygen, the level of oxygen in the room will decrease if a gas leak occurs. When oxygen levels fall below the minimum safety level, the O₂ detector will sound an alarm. Trained staff will then know to evacuate the premises until emergency assistance arrives. 

Oxygen deficiency monitors from PureAire are guaranteed to perform for 10 years. These oxygen deficiency monitors have a zirconium oxide sensor, which accurately measures air oxygen levels in temperatures as low as -40 Celsius. The O2 monitor from PureAire is an efficient, cost-effective way for plants using nitrogen, helium, or argon to keep staff safe from the known health hazards of these gases.

If you seek an oxygen monitor that needs no maintenance, no calibration, and is guaranteed to last, you may be interested in PureAire's line of products. Learn more at www.pureairemonitoring.com or by emailing info@pureaire.net for more information.