ASME B31.1 vs. ASME B31.3: Kennen Sie die Rohrleitungskonstruktionscodes
Einführung
Bei der Rohrleitungskonstruktion und -technik ist die Auswahl des geeigneten Rohrleitungscodes von entscheidender Bedeutung, um Sicherheit, Effizienz und Einhaltung von Industriestandards zu gewährleisten. Zwei der am weitesten verbreiteten Rohrleitungskonstruktionscodes sind ASME B31.1 Und ASME B31.3. Obwohl beide von der American Society of Mechanical Engineers (ASME) stammen und die Konstruktion und den Bau von Rohrleitungssystemen regeln, unterscheiden sich ihre Anwendungen erheblich. Das Verständnis der ASME B31.1 im Vergleich zu ASME B31.3 Die Diskussion ist von entscheidender Bedeutung für die Auswahl des richtigen Codes für Ihr Projekt, unabhängig davon, ob es sich um Kraftwerke, die chemische Verarbeitung oder Industrieanlagen handelt.
Übersicht: ASME B31.1 vs. ASME B31.3
What is ASME B31.3 or Process Piping Code?
ASME B31.1 ist die Norm, die die Konstruktion, den Bau und die Wartung von Kraftwerks-Rohrleitungssystemen regelt. Sie gilt für Rohrleitungssysteme in Kraftwerken, Industrieanlagen und anderen Einrichtungen, in denen Strom erzeugt wird. Dieser Code konzentriert sich stark auf die Integrität von Systemen, die Hochdruckdampf, Wasser und heiße Gase handhaben.
Typische Anwendungen: Kraftwerke, Heizungsanlagen, Turbinen und Kesselanlagen.
Druckbereich: Hochdruckdampf- und Flüssigkeitssysteme.
Temperaturbereich: Hochtemperatureinsatz, insbesondere für Dampf- und Gasanwendungen.
What is ASME B31.1 or Power Piping Code?
ASME B31.3 applies to the design and construction of piping systems used in chemical, petrochemical, and pharmaceutical industries. It governs systems that transport chemicals, gases, or liquids under different pressure and temperature conditions, often including hazardous materials. This code also covers the associated support systems and the safety considerations of handling chemicals and dangerous substances.
Typische Anwendungen: Chemische Verarbeitungsanlagen, Raffinerien, pharmazeutische Anlagen, Lebensmittel- und Getränkefabriken.
Druckbereich: Im Allgemeinen niedriger als der Druckbereich in ASME B31.1, abhängig von der Flüssigkeitsart und ihrer Klassifizierung.
Temperaturbereich: varies depending von den chemischen Flüssigkeiten, aber sie ist typischerweise niedriger als die extremen Bedingungen in ASME B31.1.
Difference Between ASME B31.3 and ASME B31.1 (ASME B31.3 vs ASME B31.1)
Sr No | Parameter | ASME B31.3-Process Piping | ASME B31.1-Power Piping |
1 | Umfang | Provides rules for Process or Chemical Plants | Provides rules for Power Plants |
2 | Basic Allowable Material Stress | Basic allowable material stress value is higher (For example the allowable stress value for A 106 B material at 250 Deg C is 132117.328 Kpa as per ASME B31.3) | Basic allowable material stress value is lower (For example the allowable stress value for A 106 B material at 250 Deg C is 117900.344 Kpa as per ASME B31.3) |
3 | Allowable Sagging (Sustained) | The ASME B31.3 code does not specifically limit allowable sagging. An allowable sagging of up to 15 mm is generally acceptable. ASME B31.3 does not provide a suggested support span. | ASME B31.1 clearly specifies the allowable sagging value as 2.5 mm. Table 121.5-1 of ASME B31.1 provides suggested support span. |
4 | SIF on Reducers | Process Piping Code ASME B31.3 does not use SIF (SIF=1.0) for reducer stress calculation | Power Piping code ASME B31.1 uses a maximum SIF of 2.0 for reducers while stress calculation. |
5 | Factor of Safety | ASME B31.3 uses a factor of safety of 3; relatively lower than ASME B31.1. | ASME B31.1 uses a safety factor of 4 to have higher reliability as compared to Process plants |
6 | SIF for Butt Welded Joints | ASME B31.3 uses a SIF of 1.0 for buttwelded joints | ASME B31.1 uses a SIF of up to 1.9 max in stress calculation. |
7 | Approach towards SIF | ASME B31.3 uses a complex in-plane, out-of-plane SIF approach. | ASME B31.1 uses a simplified single SIF Approach. |
8 | Maximum values of Sc and Sh | As per the Process Piping code, the maximum value of Sc and Sh are limited to 138 Mpa or 20 ksi. | For the Power piping code, the maximum value of Sc and Sh are 138 Mpa only if the minimum tensile strength of the material is 70 ksi (480Mpa); otherwise, it depends on the values provided in the mandatory appendix A as per temperature. |
9 | Allowable Stress for Occasional Stresses | The allowable value of occasional stress is 1.33 times Sh | As per ASME B31.1, the allowable value of occasional stress is 1.15 to 1.20 times Sh |
10 | The equation for Pipe Wall Thickness Calculation | The equation for pipe wall thickness calculation is valid for t<D/6 | There is no such limitation in the Power piping wall thickness calculation. However, they add a limitation on maximum design pressure. |
11 | Section Modulus, Z for Sustained and Occasional Stresses | While Sustained and Occasional stress calculation the Process Piping code reduces the thickness by corrosion and other allowances. | ASME B31.1 calculates the section modulus using nominal thickness. Thickness is not reduced by corrosion and other allowances. |
12 | Rules for material usage below -29 Deg. C | ASME B31.3 provides extensive rules for the use of materials below -29 degrees C | The power piping code provides no such rules for pipe materials below -29 degrees C. |
13 | Maximum Value of Cyclic Stress Range Factor | The maximum value of cyclic stress range factor f is 1.2 | The maximum value of is 1.0 |
14 | Allowance for Pressure Temperature Variation | As per clause 302.2.4 of ASME B31.3, occasional pressure temperature variation can exceed the allowable by (a) 33% for no more than 10 hours at any one time and no more than 100 hours/year, or (b) 20% for no more than 50 hours at any one time and no more than 500 hours/year. | As per clause 102.2.4 of ASME B31.1, occasional pressure temperature variation can exceed the allowable by (a) 15% if the event duration occurs for no more than 8 hours at any one time and not more than 800 hours/year or (b) 20% if the event duration occurs for not more than 1 hour at any one time and not more than 80 hour/year. |
15 | Design Leben | Process Piping is normally designed for 20 to 30 years of service life. | Power Piping is generally designed for 40 years or more of service life. |
16 | PSV reaction force | ASME B31.3 does not provide specific equations for PSV reaction force calculation. | ASME B31.1 provides specific equations for PSV reaction force calculation. |
Abschluss
Der entscheidende Unterschied in der ASME B31.1 im Vergleich zu ASME B31.3 Gegenstand der Debatte sind Branchenanwendungen, Materialanforderungen und Sicherheitsaspekte. ASME B31.1 ist ideal für die Stromerzeugung und Hochtemperatursysteme, wobei der Schwerpunkt auf mechanischer Integrität liegt. Gleichzeitig ASME B31.3 is tailored for the chemical and process industries, emphasizing the safe handling of hazardous materials and chemical compatibility. By understanding the distinctions between these two standards, you can decide which code best suits your project’s requirements, ensuring compliance and safety throughout the project’s lifecycle. Whether you are involved in power plant design or system’ processing, choosing the correct piping code is crucial for a successful project.