API RP 932-B-2019 pdf free download

API RP 932-B-2019 pdf free download.Design, Materials, Fabrication, Operation, and Inspection Guidelines for Corrosion Control in Hydroprocessing Reactor Effuent Air Cooler (REAC) Systems.
5.2 Material Selection and Design 5.2.1 The design of and material selection for equipment and piping affect their performance in REAC systems. An understanding of how differences in these equipment and piping details change the dependence upon the scope and frequency of inspection and the range of the operating envelope is benefcial to promoting reliability. Section 7 and Section 8 detail these considerations. 5.2.2 Corrosion-resistant alloys are being used more today than in the past. Alloy metallurgy can broaden the range of acceptable operating limits, simplify future inspection and process monitoring, and reduce the need for periodic maintenance and replacement. 5.2.3 Existing unit equipment and piping should be reviewed to assess their susceptibility to deterioration and ensure that a proper IOW is established and that inspection plans are in place. This review may identify areas of vulnerability where replacement or upgrading may be appropriate, considering the needs for inspection and maintenance and the constraints imposed by the operating envelope. 5.3 Establishing an Integrity Operating Window 5.3.1 An integrity operating window (IOW) is the acceptable range for operating variables in the process where the deterioration rate is predictable and tolerable. Establishing and maintaining the IOW helps prevent process conditions from subtly creeping into undesirable ranges where more rapid deterioration could result. Any consideration for operating outside the IOW should be reviewed by the SME and, if signifcant, invoke the Management of Change (MOC) process. 5.3.2 The IOW can be diffcult to establish, as several interrelated variables impact the corrosion potential. The effect of each variable and any synergistic effects on corrosion can be complex, but needs consideration. In some instances, experience within a particular unit allows a better understanding of corrosion characteristics for that unit and possibly increased fexibility in the IOW.
5.3.3 For new units, the guidance given in this recommended practice is a starting point for developing an IOW (see API Recommended Practice 584). For existing units, the current operating variables provide a basis for establishing the IOW. However, they should be compared with the industry guidelines, and those variables operating outside industry guidelines should be reviewed to determine their signifcance to deterioration. The inspection history and deterioration rate data should be reviewed to identify evidence of deterioration and determine if the system has been properly inspected. 5.3.4 IOWs are typically classifed into different levels, distinguished by risk, to set priorities on notifcations (including alarms, alerts, and/or other notifcations) and timing of actions to be implemented when IOWs are exceeded. In Recommended Practice 584, three primary levels of IOWs are proposed: “critical,” “standard,” and “informational.” These are established based on the predicted change in damage rate to equipment during an exceedance and the ability of the operator to take corrective action. 5.3.5 The specifc REAC system design is key to establishing IOWs for the system and individual equipment items/components. Listed below are typical design factors and operating variables affecting corrosion that should be considered. These include the process variables given in 6.12 and the design factors listed below: a) water injection design, such as injection quills or spray nozzles, and single versus multiple points; b) air cooler inlet and outlet piping design—balanced, unbalanced, symmetrical, asymmetric; c) air cooler design—multiple inlets, multiple row passes, single inlet, single row passes; d) use of shell and tube heat exchangers instead of REAC;e) materials of construction for piping, air coolers, separator, heat exchanger components; f) piping confguration—short-radius versus long-radius elbows, tees, etc.; g) stream velocities and fow regime; and h) feedstock composition—sulfur, nitrogen, and chlorides. NOTE Section 6 goes into more detail on process variables affecting corrosion, ending with a discussion on process monitoring and some specifc IOWs to consider in 6.12.