Explosion Proof Units

Flammable solvent units are engineered in accordance with the specifications outlined in NFPA 69, Standard on Explosion Prevention Systems. Due to the requirement for elevated concentrations of combustible solvents during cleaning operations, the primary deflagration mitigation strategy employed involves reducing oxidant concentration to suppress ignition potential.

Within these systems, the three primary solvent tanks are hermetically sealed enclosures operated under a vacuum environment to ensure complete isolation from the ambient atmosphere during active processing, idling, and shutdown phases.

This type of system is allowed under Section 5.1 that states:

5.1 Application. The technique for oxidant concentration reduction for deflagration prevention shall be permitted to be considered where a mixture of oxidant and flammable material is confined to an enclosure within which the oxidant concentration can be controlled.

Vacuum-to-Vacuum systems are engineered to precisely control oxygen levels across the entire processing apparatus. The primary vessel is evacuated to a differential pressure before the introduction of solvents. Auxiliary tanks operate under operational vapor conditions and are equipped with pressure-monitoring systems to detect potential leaks. Under vacuum conditions, solvent containment is maintained, preventing leakage.

Systems employing acetone for polymer leaching, cyclohexane for challenging flux removal, and isopropyl alcohol for medical device sterilization are standard in the industry. Integrating Vacuum-to-Vacuum systems with the VCN process constitutes a straightforward modification that has demonstrated high efficacy in field applications. Any flammable solvent with a boiling point exceeding 100°F is suitable for use.