Gypsum is calcium sulphate, and calcium sulphate is what plaster is made from. Given moisture and time against a silo wall, it does exactly what plaster does: it sets. That is why gypsum defeats aeration, vibration and most contractors' tooling.
Why vibration does not fix it. Vibrators assume the material is still a bulk solid resting against the wall. Plated gypsum is bonded to it. Energy applied to the shell travels through the plate as if it were part of the structure — which by then, mechanically, it is.
Whipping breaks the plate off the wall. Working from the top hatch, the whipsets deliver repeated impact along the bond line between plate and wall. That is the only place a set layer will fail, and it is why mechanical whipping succeeds here where surface-applied energy does not.
Cardox CO2 for the cone and the outlet, where gypsum sets thickest and where manual clearing is most dangerous. A tube fired through a wall socket breaks the mass in milliseconds without touching the vessel.
Nothing wet. Water is what set it in the first place.
Send the vessel size, the material and how long it has been a problem. We will come back with an approach, a duration and a price.
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