ASME Section VIII Pressure Vessel Code

Appropriate codes for new tank construction include ASME Section VIII Pressure Vessel Code, API 650 for Atmospheric Tanks, API 620 for Low-Pressure Storage Tanks. Appropriate codes for other aspects include ANSI/ASME B31.3 Code for Pressure Piping, the National Fire Protection Association Codes, Tubular Exchanger Manufacturers Association standards, property insurance guidelines, and any local or federal requirements. 

ASME Boiler and Pressure Vessel Code. The ASME Boiler and Pressure Vessel Code is pubhshed in 11 sections. Section VIII, which is concerned with rules for the design of unfired pressure vessels, was first pubhshed in 1925 and since 1968 it has been issued in two parts. Division 1 (147) and Division 2 (148), the latter being known as the Alternative Rules. 

ASME. Boiler and Pressure Vessel Code, Sections I and VIII. American Society of Mechanical Engineers. 

The ASME code provides the basic requirements for over-pressure protection. Section I, Power Boilers, covers fired and unfired steam boilers. All other vessels including exchanger shells and similar pressure containing equipment fall under Section VIII, Pressure Vessels. API RP 520 and lesser API documents supplement the ASME code. These codes specify allowable accumulation, which is the difference between relieving pressure at which the valve reaches full rated flow and set pressure at which the valve starts to open. Accumulation is expressed as percentage of set pressure in Table 1. The articles by Rearick and Isqacs are used throughout this section. 

This figure conforms with the requirements of Section VIII of the ASME Boiler and Pressure Vessel Code. 

Boiler and Pressure Vessel Code, Section II, Materials (Part A, Ferrous Material Specifications, and Part D, Properties ), Section ID, Rules for Construction of Nuclear Power Plant Components, and Section VIII, Pressure Vessels, Divisions 1 and 2. Code for Pressure Piping, ASME/ANSI B31.3, Chemical Plant and Petroleum Refinery Piping ... 

The ASME Boiler and Pressure Vessel Code, Section VIII, is the standard resource for the design, fabrication, installation, and testing of storage tanks and process vessels rated as pressure vessels (i.e., above 15-psig design). ASME B31.3 is a basic resource for process piping systems. 

Fired pressure vessels should be designed and constructed in accordance with Section I (Power Boilers), or Section VIII, Division 1 or Division 2 (Pressure Vessels), as applicable, of the ASME Boiler and Pressure Vessel Code. 

FIG. 10-195 Quick reference guide to ASME Boiler and Pressure Vessel Code Section VIII, Division 1 (2004 edition). Reprinted with permission of publisher, HSB Global Standards, Hartford, Conn.)... 

ASME Boiler and pressure vessel code, Section VIII, Pressure vessels ... 

ASME VIII, "Boiler and Pressure Vessel Code, Section VIII, Pressure Vessels", ASME... 

With the expansion of the process industries, the need for a code that would be applicable to unfired vessels (roughly, every pressure-containing vessel that is not a boiler) was identified, which gave rise to the Section VIII of the ASME code. Today, the ASME Boiler and Pressure Vessel Code is composed of 12 sections ... 

So among specialists there are apparently different interpretations or understandings on what API 520 and the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1, are really saying, while it is these organizations which are setting the codes that determine how pressure vessels are to be designed and protected. Remember that these codes are law and must be followed. 

Here it should be noted that some manufacturers have their own formulas for their specific valves. In general, the following formula can be used conservatively in accordance with the rules set by the ASME Boiler and Pressure Vessel Code Section VIII. 

The necessary wall thickness for metal vessels is a function of (1) the ultimate tensile strength or the yield point of the metal at the operating temperature, (2) the operating pressure, (3) the diameter of the tank, and (4) the joint or welding efficiencies. Table 4 presents a summary of design equations and data for use in the design of tanks and pressure vessels based on the ASME Boiler and Pressure Vessel Code as specified in Section VIII of Division 1. 

Pressure Relief Valves Definitions for pressure relief valves, relief valves, pilot-operated pressure relief valves and safety valves, are found in the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1, Rules for Construction of Pressure Vessels, Paragraphs UG-125 and UG-126. The pressure-relief valve is an automatic pressure relieving device designed to open when normal conditions are exceeded and to close again when normal conditions are restored. Within this class there are relief valves, pilot operated pressure relief valves, and safety valves. 

Construction Codes Rules for Construction of Pressnre Vessels, Division 1, which is part of Section VIII of the ASME Boiler and Pressure Vessel Code (American Society of Mechanical Engineers), serves as a construction code by providing minimum standards. New editions of the code are usually issued every 3 years. Interim revisions are made semiannually in the form of addenda. Compliance with ASME Code requirements is mandatory in much of the United States and Canada. Originally these rules were not prepared for heat exchangers. However, the welded joint between tube sheet and shell of the fixed-tube-sheet heat exchanger is now included. A nonmandatory... 

Anonymous, ASME Boiler and Pressure Vessel Code, Section VIII, Div. 1, American Society of Mechanical Engineers, New York, NY, 1980. Anonymous, Heat Exchangers for General Refinery Service, API Standard 660, American Petroleum Institute, Washington, D.C. 

If the CRM lined vessel operates at ambient temperature or so that there is a nelgligible thermal difference between the inside and outside of the vessel, then the thickness of the steel shell should be calculated by the rules of the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1 taking into account the following stresses ... 

The ASME Boiler and Pressure Vessel Code, Division VIII, Section 1, Paragraph UG-81 permits an out of roundness maximum of 1% variation of all diameters from the nominal diameter. This is not sufficient to assure a satisfactory CRM lining. A German standard DIN 28050, Section 4 (10.54 issue) specifies that the roundness shall be determined by measuring the radians and that the radians must not vary more than +0.4% from the average value in the cylindrical part of the apparatus to be CRM lined after final erection. 

Maximum design temperature for ASME Boiler and Pressure Vessel Code Section VIII Division 2 < 900°F... 

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