Powder charging

Figure 11. Model for electrostatic hazards associated with the accumulation of charged powders, based on Glor (1988).

In the case of charged powder entering a silo, the Maurer discharge mechanism continuously dissipates charge as shown in Fig. 10. The details of this mechanism—thresholds, inlet flow requirements, etc.—are not as well-documented or understood as they should be. 

An equal and opposite charge is also accumulated in the powder in the insulated drum. Therefore the charged powder is another ignition source. For example, if a grounded object of any kind is placed close to the solids, an energetic spark could be generated. 

The ballistic bomb (pressure bomb, manometric bomb) is used to study the burn-up properties of a -> Gunpowder or -> Propellant charge powder. It consists of a pressure-resistant (dynamic loading up to about 1000 MPa (10000 bar) hollow steel body that can be bolted... 

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