Abstract: A porous plug retainer which can be mounted in a hot metal ladle or similar vessel for locating, installing and retaining an argon porous plug so as to allow service and maintenance of the porous plug to be performed from outside the vessel. The porous plug retainer is comprised of two subassemblies with the first subassembly welded to the bottom of the hot metal ladle and machined to accept a female refractory block into which the porous plug is inserted. The porous plug is formed so that it fits and mates with the opening in the female refractory block and the second subassembly can be joined to the first subassembly so as to lock the members together. The second subassembly is mounted on a hinge to allow it to move linearly and then radially to clear the porous plug while opening. The invention allows the porous plug to be properly aligned in the refractory block and a threaded seat allows the porous plug to be firmly positioned in the refractory block.