The inert gas glove box is a piece of equipment used to confine processes or products under a controlled atmosphere. This device allows users to create a working environment suitable for the manipulation of products or processes reacting to oxygen and/or water. The enclosure prevents any contact between the product and the atmosphere by protecting it. When should you use an inert gas glove box and how does it work?
What is an Inert Gas Glove Box?
An inert gas glove box is a hermetic device designed for the storage and handling of processes and compounds sensitive to humidity or air. Its hygrometry and oxygen levels are fixed at less than 1 ppm. Argon, helium or nitrogen are the types of gas considered to be neutral or inert, allowing them to replace the air inside the glove box. The enclosure allows for TIG welding under argon.
The glove box is also necessary for repairing and welding various titanium parts, super alloys such as Hastelloy, Inconel and Monels and noble alloys.
A series of devices accompany the enclosure for containment in an inert atmosphere, in order to purify and circulate the inert gas inside it. To make room for an inert environment, the glove box eliminates water, solvents and oxygen. There are two purification systems for gaseous glove boxes:
The closed loop gas purifier – The gas and atmosphere are continuously purified by means of the purifier and a closed loop circulation. This reduces the consumption of inert gas in the enclosure.
Lost scavenging – The atmosphere in the glove box is renewed by a continuous flow of inert gas in and out. This process is also called lost gas flushing. Conversely, the enclosure consumes a significant amount of inert gas.
The pressure inside the chamber is slightly above atmospheric pressure. If, over time, the gloves become porous or if there are micro-leaks, this overpressure prevents outside air from entering the device.
Why Work in an Inert Atmosphere?
Operations or product handling are safe when they are carried out inside a glove box in which the atmosphere is inert. The glove box constitutes a protective device which maintains the purity of humidity and oxygen, in order to prevent possible reactions. The enclosure thus acts as a physical barrier between the atmosphere and the operations/products.
The main chamber of the enclosure has transparent walls with integrated handling gloves. This ensures that the containment is not compromised and also secures the manipulations. The number of integrated gloves depends on the needs of the workstations, the layout of the instrumentation inside and the operations which are being carried out. The presence of transfer locks allows for the transfer of samples, the different tools and the parts necessary for the manipulations.
Safety components (regulators, safety valves and alarms, humidity, nitrogen and oxygen sensors) are also integrated into the inert gas glove box and guarantee its proper functioning. The presence of a safety valve allows excess gas to be evacuated, thus avoiding excessive internal pressure in the glove box. Each operation requires different containment conditions (pressure, temperature, protective gas, etc.), depending on the sector. Regulators also allow for control of the working environment.
Many sectors can resort to the use of a glove box under inert gas. It is widely used in the space and aeronautics industries, in organometallic chemistry, research and development, microelectronics, semiconductors, solid state physics, biology, etc.