API RP:2001 pdf download

API RP:2001 pdf download.Fire Protection in Refineries.
5.4.2 Materials of Construction
The “suitability for intended use” of materials at a refinery has a bearing on fire loss risk. The standards, specifications, and recommendations of nationally-recognized authorities should be consulted and applied where relevant. In many instances, specifications have been promulgated by API to meet the particular needs and requirements of oil refineries. Additional information is available in the publications such as those listed in the bibliography from organizations such as the American Society for Testing and Materials (ASTM); the American Society of Mechanical Engineers (ASME); NFPA; the American Society for Metals (ASM); the National Association of Corrosion Engineers (NACE); and Underwriters’ Laboratories, Inc. (UL).
A careful review and selection of materials by qualified personnel decreases the potential for materials failure. Proper selection of the materials of construction requires a thorough knowledge of the internal process, the exterior environment, failure modes, correct material application and fabrication techniques, maintenance philosophy, and inspection intervals. Positive material identification (PMI) programs provide a quality-control method for preventing the unintended use of inappropriate materials, helping to avert one potential cause of material failures. For example, PMI programs can include training for awareness and identification of suspect and potentially counterfeit bolts.
Corrosion is a recurring cause of loss of containment of flammable and combustible materials leading to fires. The potential for unexpected corrosion is therefore one of the most important factors in selecting the materials of construction and maintaining surveillance programs. See the relevant API publications for internal and external inspection of refinery equipment (some are listed in the bibliography).
The basis for selection of materials is the performance of the materials under process design conditions and the interaction of the materials with the external environment. Operating conditions include start-up, shutdown, and upset conditions. Any potential problem anticipated with a particular material should be discussed during hazard analysis sessions. It is important that personnel with relevant expertise be consulted during material selection.
5.4.3 Mechanical Design and Equipment Construction
5.4.3.1 General
Refinery processes frequently operate at high pressures and temperatures that put stress on equipment. Equipment used in the process must be designed to withstand the stresses of the operating conditions to which it will be subjected.
In addition to a quality control program for materials, a sound quality control program for equipment construction is important and should be in place for construction activities to verify that “as-built” construction is in conformance with design specifications.
5.4.3.2 Pressure Vessels
5.4.3.2.1 General
Design and construction specifications for vessels subject to pressures of 15 psi gage or more are given in ASME Boiler and Pressure Code, Section VIII: Unfired Pressure Vessels.
Suitable provisions must be made for cleaning and ventilating a vessel when it is inspected internally. It should be isolated from other equipment and from flammable, toxic, or inert materials. Appropriate precautions (such as water washing) should be used if inerted to address potential pyrophoric residue concerns.
Reactors, columns, exchangers, and boilers are typical pressure vessels found in a refinery that require special design considerations for structural supports, instrumentation, and protective systems.
5.4.3.2.2 Internal Design
Internal design of vessels should avoid pockets where the lack of drainage would allow water (or hydrocarbons) to accumulate, particularly during start-up. Proper placement of vent piping can avoid bypassing and allow effective purging of otherwise trapped condensable gases, which could leave water or light hydrocarbons in equipment. The sudden generation of steam caused by the contact of hot-oil charge stocks with water can result in dangerous overpressure of equipment. Hydrocarbons retained in equipment can create future fire (or industrial hygiene) concerns.