... Currently 5 common diameter-1830mm,2750mm,3670mm,4600mm,5500mm,with half-ring,1-ring,2-ring,3-ring ... famous steel factories.All steel plates are passivation treated,with zn-coating thickness no less than 275 gram ... HumanizedSilo ladder stair is strong and slip resistant,assembled with guard rail to ensure safety,thus more humanistic. ... Silo adapter and boot Our factory picture Silos with Hopper Bottom