Procedure 6-4 Design of Vessels with Refractory Linings

Procedure 6-4 Design of Vessels with Refractory Linings [9-12] 

Vessel engineers must eventually become familiar with refractory materials, techniques, strategies and installation in order to properly specify, analyze and check vendor designs for refractory lined vessels, equipment and components. Refractory lining is utilized as a heat barrier, insulator, or as an abrasion resistant lining, or both. Dual component linings are utilized for insulating and abrasion resistance. 

Refractory materials can be attached to the skin by a variety of anchorage methods. The refractory itself may be put into place by casting, vib-casting, gunniting or ram packed. Anchorage methods, the metal parts that hold the refractory to the metal skin, can be steer bar, wavy V, hex mesh, S bar and various types of punch tabs. 

Every refractory has a limited service temperature, or maximum temperature. Above these temperatures brick linings are used. The cutoff of refractory in lieu of brick is about 1800°F. Bricks have the capacity to seal and return to shape after heating without spalling. Sohd monolithic linings do not. In addition, bricks can be made in thicker sections than can be cast from refractory. 

The cracks formed in monolithic linings above these temperatures are too severe for the material to recover. In the early day of FCC units, the regenerators and reactors were brick lined, like furnaces, because the technology of gunnited and cast linings was not capable of withstanding the service. Brick linings are still utilized in a variety of applications. Shapes are available to conform to cylindrical shapes of containers most commonly used in these vessels and equipment 

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