تعتبر الفلنجات مكونات مهمة في أنظمة الأنابيب, السماح اتصالات آمنة وفعالة بين الأنابيب, الصمامات, مضخات, والمعدات. لضمان السلامة, التوافق, والأداء, the production and use of flanges are governed by international standards. من بين هؤلاء, أنسي و ASME are the most widely recognized, but there are also other standards like DIN, JIS, بكالوريوس, و إن. Understanding these standards is essential for engineers, المتخصصين في المشتريات, and industries dealing with global supply chains.

This article explains the major flange standards—ANSI, ASME, and others—highlighting their scope, key features, and importance in industrial applications.

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Why Flange Standards Are Important

1. Safety and Reliability
   Standards ensure flanges can withstand the pressure and temperature conditions of different industries.

2. قابلية التبادل
   Flanges from different manufacturers must fit together, which requires adherence to common standards.

3. Global Trade
   International projects often involve equipment from multiple countries, making standardized flanges critical for compatibility.

4. Quality Assurance
   Standards specify material composition, تقييمات الضغط, أبعاد, وإجراءات الاختبار.

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ANSI Flange Standards

أنسي (المعهد الوطني الأمريكي للمعايير) establishes guidelines for various products, بما في ذلك الشفاه. ANSI flange standards specify:

• أبعاد (القطر, سماكة, دائرة الترباس, إلخ.)

• تقييمات درجة حرارة الضغط

• Facing types (وجه مرفوع, وجه مسطح, آر تي جيه)

ANSI flange standards are widely used in the United States and in industries such as oil and gas, البتروكيماويات, وتوليد الطاقة.

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ASME Flange Standards

ASME (American Society of Mechanical Engineers) issues detailed codes for pressure vessels, أنظمة الأنابيب, والشفاه.

• ASME B16.5: Flanges up to 24 بوصة في القطر

• ASME B16.47: الشفاه ذات القطر الكبير (26–60 inches)

• ASME B16.36: الشفاه الفوهة

• ASME B16.48: Line blanks

ASME standards are stricter than ANSI in terms of design rules, اختبار, and quality control. Many engineers today use the terms ANSI and ASME interchangeably, but technically, ASME has replaced ANSI for flanges in modern practice.

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Other International Flange Standards

1. DIN (Deutsches Institut für Normung – Germany)

• Common in Europe and Asia

• Specifies PN (الضغط الاسمي) ratings such as PN6, PN10, PN16, بي إن 40

• Used in chemical plants, المصافي, ومحطات الطاقة

2. EN (European Norms)

• Harmonized standard across the European Union

• Replaces older DIN standards in many regions

• Ensures compatibility across EU member states

3. بكالوريوس (British Standards)

• Historically used in the UK

• يغطي الشفاه, الحشيات, and bolting specifications

• Now gradually aligned with EN standards

4. JIS (المعايير الصناعية اليابانية)

• Widely used in Japan and some Asian markets

• Specifies flanges for industrial piping systems

• Popular in shipbuilding, السيارات, and petrochemical sectors

5. ISO (International Organization for Standardization)

• Provides global harmonization

• Ensures compatibility in international trade and projects

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Pressure Classes in Flange Standards

Different standards classify flanges by pressure capability:

• ANSI/ASME Classes: 150, 300, 600, 900, 1500, 2500

• DIN/EN PN Ratings: PN6, PN10, PN16, PN25, بي إن 40, PN64, PN100

• JIS Pressure Ratings: 5ك, 10ك, 16ك, 20ك, 30ك

These classifications indicate the maximum pressure a flange can handle at a specific temperature.

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Flange Facing Types Defined by Standards

1. وجه مرفوع (الترددات اللاسلكية): Most common, allows better gasket compression.

2. وجه مسطح (FF): Used when bolting against cast iron or non-metallic surfaces.

3. نوع الحلقة المشتركة (آر تي جيه): For high-pressure, تطبيقات درجات الحرارة العالية.

4. اللسان والأخدود: Provides tight sealing in specialized applications.

Standards specify exact dimensions for these facings to ensure seal integrity and compatibility.

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Materials Specified in Flange Standards

• الكربون الصلب: For general applications with moderate pressure and temperature

• الفولاذ المقاوم للصدأ (304, 316, 321, 347): For corrosive and high-temperature environments

• سبائك الصلب (F11, F22, F91): For high-pressure and high-temperature service

• الدوبلكس والسوبر دوبلكس ستانلس ستيل: For offshore and marine environments

• سبائك النيكل (إنكونيل, مونيل, هاستيلوي): For extreme chemical and thermal conditions

By adhering to standards, manufacturers and buyers ensure materials match required service conditions.

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Key Differences Between ANSI, ASME, and Other Standards