scope:

This recommended practice (RP) provides recognized industry practices, requirements, and guidance for the installation, in-service inspection, and repair assessment of refractory lining installed into equipment that is used in general refinery services. Refinery equipment included in the scope of this standard includes, but may not be limited to, Fluid Solids Units-including Fluid Catalytic Cracker Units (FCCUs), Reforming Units, Fired Heaters, Incinerators, Sulfur Recovery Units, Flue Gas Ducts, Calciners, Steam-Methane Reformers (SMRs), Cracker Furnaces, Boilers, Hydrogen plant and transfer lines, and Flue Gas Stacks.

Inspection and quality control for design and installation of new, patch repair or replacement lining systems are covered in separate API documents, including:

- API Standard 936, Refractory Installation Quality Control-Inspection and Testing Monolithic Refractory Linings and Materials

- API Standard 975, Refractory Installation Quality Control-Inspection and Testing of Refractory Brick Systems and Materials

- API Standard 976, Refractory Installation Quality Control-Inspection and Testing of Fiber Linings and Material

Proper inspection and assessment of the refractory linings is essential to maintain equipment reliability, operating efficiency, personnel safety, and operational process safety. Observations are based on internal visual inspection. Refractory may be installed into refinery equipment for one, or a combination of, several reasons:

a) Thermal protection of equipment-Refractory can protect the structural components of the process equipment from a variety of thermal degradation mechanisms, such as, high temperature oxidation, thermal fatigue, carburization, creep, sulfidation, high temperature hydrogen attack, graphitization, and others.

b) Process efficiency and energy retention-Refractory can retain heat inside the equipment which improves the efficient operation of the refinery unit and reduces thermal energy losses to the atmosphere.

c) Resistance to abrasive process-Severe erosion can occur in some refinery equipment, and refractory linings can help reduce abrasive damage to the equipment.

d) Resistance to corrosion-Refractory linings can, in some cases, reduce the rate of damaging reactions by corrosive compounds in the process on the containment vessel, duct, firebox or pit.

e) Personnel safety-The internal temperature of equipment can be very high, and refractory can be used to reduce the external equipment temperature to a lower level to help prevent personnel injury.