It only takes a tiny spark or a sufficiently hot surface to ignite a deadly explosion. For many industries that depend on electrically driven pumps, explosion prevention is a primary safety concern. In the case of chemical plants, refineries and hydrocarbon processors, a high potential exists for explosive vapors to be emitted by process and other liquids. In the case of mining and oil and gas exploration, an explosion's potential fuel source is escaping underground gas from subsurface pockets, which are frequently under extreme pressure. In response to these potentially destructive situations, electrical equipment, including submersible pump motors, can be designed and manufactured to prevent them from becoming an ignition source in these hazardous environments.
Pumps for Hazardous Zones
Safety in these environments begins with the science of defining the exact nature of the hazardous area. This includes understanding and classifying the explosive material and its potential for being present within defined areas (zones) of the considered site. In the U.S. and some other countries, hazardous locations are defined in an official and comprehensive publication called the National Electric Code (NEC), which is produced and maintained by the National Fire Protection Association (NFPA). The NFPA's mission includes producing fire safety standards that are used as official codes by governments and other authorities with interest in safety for construction, commercial, residential and industrial sites.- Spark-free motor design. The pump motor must be designed so its operation will not produce electrical sparks, a source for ignition.
- Engineered flame paths. In the event that explosive gas enters and ignites inside of the motor housing, the motor's design must cause the flame to extinguish before it would exit the vessel.
- Pressure containment. The motor vessel's structure must be capable of containing the pressure generated by an internal explosion without fracturing.