Positive pressure gloveboxes are employed by companies around the world to enclose a variety of manual and automated manufacturing processes from 3D printing and welding, to semiconductor, solar cell, LED, Lithium ion (Li) battery, medical device, pharmaceutical and chemical production. As many of these processes require a particle-free, non-reactive, inert atmosphere, argon or nitrogen gas is commonly introduced into the glovebox chamber to create the ideal, non-volatile, working environment. (A common industry goal is maintaining < 1 ppm of oxygen (O2) and water (H2O) vapor, which in comparison to clean room standards, would be better than a class 10 environment). Traditionally, trained operators will manually fill and purge, and visually monitor the gas and effectively “dial-in” the atmospheric condition. There are four known pitfalls of this manual approach, however, that continue to raise the urgency in many factories to adopt more sophisticated, digitally-controlled glovebox systems.

First, in the time it takes to make a tool change, or to process even a small lot, subtle to dramatic fluctuations in the environment can occur. This can result in product losses during final inspection, or worse, allow undetected lower reliability lots to get shipped. Second, safety procedures relative to regulating the proper atmospheric condition is often trained and built into a manufacturer’s human process. Since excessive levels of oxygen or water vapor are volatile in certain procedures, serious safety concerns are raised if, say, the trained operator goes out sick and production is left to a less experienced operator. Third, argon and nitrogen gas consumption in many factories is a notable expense. Taking a fill and purge approach, which also includes downtime, is recognizably low in efficiency, especially as compared to a digitally controlled gas management system which filters and recycles the argon or nitrogen gas continuously. Fourth, manual processes will, at-best, have a nearby PC-based or hand-written documentation process with broad log times. Whereas today’s digitally managed systems will log traceable data for every second the glovebox is in operation and will auto-correct themselves instantly. Data can also be shared anywhere in the world it’s being managed, often through a Machine-to-Machine (M2M) or IoT network.

As more stringent regulations over consistent quality and repeatable processes trickle down from Tier 1 military and aerospace OEMs into broader electronic and mechanical device suppliers, more consistent and efficient gas management systems are increasing in demand. From production, Q/A, and supply chain managers who are looking for increased reliability and documented lot-to-lot data, to researchers developing unique processes and exploring new material and chemical combinations, the sophistication of a digitally controlled system is becoming crucial.

As gas monitoring and control requirements have evolved, so too have the digital electronics and programmable logic controllers (PLC) that enable it. Capitalizing on this trend, Inert, an Amesbury, Mass. designer and manufacturer of integrated glovebox systems, has recently partnered with Siemens to centralize their approach.

Inert’s PureLab HE 4GB 2500 glovebox system is the company’s most popular product line now taking advantage of the Siemen’s partnership. This four glove (or two station) system is employed in research and development labs at universities and at various factories performing any number of device assembly (including OLED and semiconductor), welding (ARC, Tig or Laser) and 3D printing (additive manufacturing) procedures.  Its factory space requirements of 10 ft x 6 ft x 3.5 ft, and internal work space of approximately 8 ft x 3 ft x 2.5 ft―combined with its robust steel construction (capable of handling 550 lbs. on each of four, or six, casters)―make this a versatile glovebox for many manufacturing and research procedures. Designed as a modular system, PureLab HE also allows for pre-delivery and onsite add-ons and customer-specific tooling.

From Siemens’ Totally Automated Integration (TIA) portfolio, Inert selected the SIMATIC S7-1200 PLCs and SIMATIC human-machine interface (HMI) color panels. The Siemens PLCs offer Inert high-reliability regulation of a multitude of critical, automated system requirements, such as temperature and airflow compensation. With the common engineering framework of the TIA platform, multiple gas management systems are managed from a single interface, and color HMI panels are tailored to specific languages and protocols. Data retrieval is easily done on touch screens or from the convenience of a centralized PC. These options present a unique customer opportunity for remote access to system diagnostics, as well.