Designing fan bulkhead - is there minimum blast pressure
Designing fan bulkhead - is there minimum blast pressure
(OP)
We're designing a bulkhead (58' wide x 30' tall) for a large volume, low pressure Howden mine fan. The operating pressure for this fan is less than 1 inch of H20 (5.2 psf). The customer doesn't have any information on blasting pressures unfortunately. Obviously I need to talk with the customer and try to sort this out, but in the meantime, does anyone know if MSHA has a minimum blast pressure requirement? I would think that blast pressure would govern over this minimal fan pressure.





RE: Designing fan bulkhead - is there minimum blast pressure
RE: Designing fan bulkhead - is there minimum blast pressure
RE: Designing fan bulkhead - is there minimum blast pressure
It might be easier and more effective to focus on the anticipated peak particle velocity at the bulkhead due to any specific blast . This is also a function of the distance betrween the blast and the amount of explosives being detonated instantaneously. The rule of thumb is a PPV of 300 mm / second will crack virgin rock, less than 50 mm/ second is unlikely to crack drywall. ie anything around 100- 150 mm / second should be OK underground. Run the calculations and make sure you are likely to be below 150mm/sec for every blast. If you cant confirm that, then your structure is at risk.
RE: Designing fan bulkhead - is there minimum blast pressure