Monday, May 22, 2017

Titanium Demand on Rise for Additive Manufacturing Printing: How it’s Made? Titanium Plasma Atomization


                                                                                                                                      Link to oxygen sensors
Plasma atomization is used in many applications, including 3D printing. First developed in 1998, this technique has risen to become the industry standard process for creating reactive metal powders suitable for 3D printing. Learn how plasma atomization works and why you need an oxygen monitor to stay safe with plasma atomization. 

How Plasma Atomization Works

Plasma atomization is used not only in 3D printing, but in any circumstance where powder metallurgy is needed. Other uses include spray coating, cold spray, and metal injection molding. 
To pulverize metal, wire is fed through a tube, then hit by three plasma torches capable of reaching temperatures of 10,000 degrees Celsius. As the wire liquefies and melts, individual droplets shear off and fall into a chamber filled with argon gas and cooled by water. When the drops of metal hit the argon, they solidify into spherical droplets. This process produces a fine, uniform metal powder. After the wire has been transformed into droplets, the powder is sieved to ensure uniformity. This is key to the success of the 3D printing process, which relies upon fine grade, uniform powder. 

Titanium (Ti), Nitinol, Niobium, Aluminum, and other reactive metals and their alloys can all successfully be atomized through this process. Variables in the plasma atomization process allow workers to create droplets of different sizes, for different end uses.  

PureAire offers an oxygen analyzer, which many 3D printing manufacturers utilize. This device helps monitor the levels of oxygen in ppm, from 0 to 1000, while the atomization process takes place. 
It's important to keep oxygen levels low while the Ti and other base metals are being turned into powder, as this ensures the purity of the final product. Oxygen analyzers provide a continuous readout of oxygen levels inside the chamber, so your workers can ensure the highest levels of purity at a glance. 

Argon gas is used during plasma atomization because it helps ensure the purity of the powdered metal by reducing the chance for chemical reactions that might happen if oxygen interacted with the metal during the atomization. As long as the argon gas remains in the chamber where the aluminum or titanium powder is being made, plasma atomization is quite safe. Like other inert gases, argon depletes oxygen from the atmosphere. Were the argon gas to leak out of the plasma atomization chamber, employees' wellbeing could be at risk. 

Why You Need an Oxygen Monitor with Plasma Atomization

When argon escapes into the environment, it displaces oxygen molecules. Since the gas is both odorless and colorless, there is no way to detect an argon leak by sight or smell. If there are several atomization stations creating Ti or titanium powder at once, the risk increases exponentially. 
Once oxygen levels begin to drop, worker safety becomes a concern. If oxygen levels fall below the minimum set by OSHA, workers can suffer respiratory and cognitive impairment. Symptoms include dizziness, confusion, fatigue, and shortness of breath. Even a brief exposure to an oxygen deficient environment can prove deadly. 

Fortunately, an oxygen deficiency monitor can continually weigh oxygen present in the room, alerting staff before oxygen levels plunge below the OSHA threshold. This provides sufficient notification via flashing lights and loud alarms for staff to exit the room to safety. 

PureAire offers an oxygen monitor with a zirconium sensor. Unlike other sensors, this lasts with no maintenance and no calibration once the O2 monitor is installed. The O2 monitor and oxygen analyzer, when used together, allow for precise manufacturing of powdered metals with low risk to workers. Businesses prefer PureAire products, which are low-maintenance, cost-effective, and reliable for 10+ years. Visit www.pureairemonitoring.com to learn more about our oxygen analyzers and monitors. 

 

Tuesday, May 9, 2017

University Environmental Health & Safety Departments: Handling Compressed Nitrogen and Cryogenics



An explosion at a university research lab in Hawaii last year highlights the dangers of working with compressed gas and the need for safety equipment on campus. Learn the dangers of working with compressed gas, how an oxygen deficiency monitor can help, and campus safety best practices. 

Compressed Gas on Campus: Uses and Dangers


Compressed gases including nitrogen, argon, and oxygen are widely used on campuses. These gases have many practical and educational uses across educational institutions. While the level of risk varies across schools, a few examples will illustrate the benefits and the risks of using compressed gas on campus.

Argon gas is critical in the 3D printing process, which campus design, fine arts, applied arts, and sciences may use. Culinary programs may use liquid nitrogen for cooking and freezing, and chemistry labs may use N2 as well. Autoclaves, which sterilize equipment, are regularly used in scientific, medical, and industrial programs. Sports programs and physical therapy training programs may use cryotherapy for injury recovery. Cryotherapy chambers rely on nitrogen to chill the air. The chambers can turn deadly if a nitrogen leak occurs. These gases may be used by facilities personnel, researchers, faculty members or teaching assistants and students assisting with teaching labs. No matter which gas students are working with, they are at risk if the gas is not handled, used, stored, or transported properly. 

As these few examples illustrate, there are many opportunities for dangerous leaks, explosions, or fires on campus if safety protocol isn't followed. Many schools find the gases are not properly stored, which leaves everyone on campus in danger. A recent safety bulletin from the University of Rochester found that liquid nitrogen was stored without an oxygen sensor, poisonous gas was used with a fume hood that did not adequately vent hazardous fumes, gas cylinders were modified using unacceptable materials, and gas tanks were stored without protective chains, stands, and gas caps. 

Why Schools and Universities Need an O2 Monitor 

As the incident in the Hawaiian university lab illustrates clearly, compressed gases pose significant health risks in the university setting. Whenever safety protocol is not followed, the tanks are at greater risk of tipping, falling over, or leaking. 

While the lab worker escaped with her life, many others have not been so lucky. A nitrogen (N2) gas leak causes death via asphyxiation in a matter of minutes. 

Nitrogen gas is both odorless and colorless. If gas leaks from a canister, there is no way for passerby to tell. As the gas leaks, it lowers ambient oxygen levels below safe thresholds. When levels of oxygen in the air fall below 16 percent, people can experience adverse health affects. Additionally, university property can be damaged by fires or explosions. 

All it takes it a couple of breaths of oxygen-deficient air for symptoms including confusion, dizziness, fatigue, muscular aches, lack of consciousness, and even death. 

Given the clear dangers that these gases pose, universities and schools must take steps to protect their students and staff. Fortunately, there is an easy and cost-effective way to detect gas leaks and alert everyone before oxygen is depleted from the air: Installing an O2 monitor. 

An O2 monitor, also called an O2 deficiency monitor, measures levels of oxygen in the air all the time. As long as the air has adequate oxygen, the monitor will stay silent. When levels fall below safe thresholds, the oxygen deficiency monitor will flash lights and sound an alarm. This way, everyone in the vicinity of the leak can escape without suffering adverse health effects. 

An O2 deficiency monitor should be installed anywhere that these gases are used or stored. Universities and schools may wish to equip labs, storage facilities, equipment rooms, and hallways or corridors that connect storage rooms with labs or classrooms where the gas is used. 

PureAire offers robust oxygen deficiency monitors that feature best in class construction. Made with zirconium oxide sensors, these monitors offer 10 or more years of maintenance-free performance once installed. These monitors can detect leaks of gases including argon, nitrogen, and helium. View PureAire's line of oxygen deficiency monitors at www.pureairemonitoring.com.