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Safety

Exhaust and relief

Slow dump, screaming relief, delayed release, over-pressure. Treat a stuck relief as a stop-work, not a noise complaint.

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When you dump a pot, air and dust leave through the exhaust muffler. Pack that element with slag dust and the vessel takes minutes to go soft. Crews then hammer the valve or, worse, blank the relief to kill the hiss. A blanked relief is how a vessel over-pressures. Treat chatter or a stuck relief as stop-work.

Function-test the relief at the start of a shift: it must lift and reseat. If it screams and will not sit, replace the seal or the whole valve. Do not wrap it in rag. BLAST APEX pots are industrial vessels; the relief is not decoration. Clean the muffler housing when dump time doubles versus a new pot.

Exhaust circuit

SymptomCauseAction
Slow depressuriseMuffler packed with dustClean housing, replace element
High-pitch noiseRelief not seatingTest, replace seal
Delayed vessel dumpExhaust restrictionPurge dump lines
Vessel over-pressureRelief blocked or seizedReplace valve before next fill

BLAST APEX pots are built for industrial duty. Do not blank a relief to “stop the hiss”. That is how vessels fail.

Engineer FAQs

Relief valve chatter: can we keep blasting?

No. Function-test. Replace the seal or the valve. A seized relief is an over-pressure event waiting. ASME pots are not optional jewellery.