Flanges are vital components used to connect pipes, バルブ, パンプス, and other equipment in various industrial systems. 安全を確保するために, 互換性, そしてパフォーマンス, flanges are designed and manufactured according to internationally recognized standards such as ASME B16.5, EN 1092-1, DIN, JIS, その他.

Understanding flange standards requires familiarity with several key parameters. その中で, three critical parameters determine the functionality and interchangeability of flanges: 圧力定格, 顔のタイプ, そして 寸法公差. These parameters not only affect the mechanical integrity of the flange but also dictate how well it mates with piping systems.

この記事では, we will explore these three important parameters in detail and explain why they are essential for manufacturers, エンジニア, および調達スペシャリスト.

Company Logo: ササフランジ

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Parameter 1: 圧力定格 (Class or PN)

What is Pressure Rating?

The pressure rating of a flange indicates the maximum pressure it can withstand under specified temperature conditions. It is a critical factor in ensuring the safety and durability of a piping system.

Depending on the standard used, pressure ratings are represented differently:

• ASME/ANSI: クラス 150, 300, 600, 900, 1500, そして 2500

• 1 つ/あなたの: PN 6, PN 10, PN 16, PN 25, PN 40, PN 64, 等.

Why Pressure Rating Matters

Choosing the correct pressure class ensures the flange can resist system pressure without deformation, 漏れ, または失敗. If the pressure rating is too low, it can result in catastrophic consequences including pipe rupture, environmental contamination, or injury.

Factors Influencing Pressure Rating

• 材質グレード: ステンレス鋼, 炭素鋼, and duplex have different pressure capacities.

• 温度: Higher temperatures lower the effective pressure resistance.

• デザイン: 厚さ, ボルトパターン, and face type influence pressure class.

Pressure Rating Example

クラス 150 flange made from stainless steel may handle a maximum of 19.6 bar at 100°F, but this drops significantly as temperature increases. 同様に, a PN40 flange is rated for 40 バー under ambient conditions, but the actual performance depends on the material and temperature.

sasaflange provides pressure-tested flanges across all classes and PN levels, in compliance with ASME and EN specifications.

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Parameter 2: フランジ面の種類

What is Flange Face Type?

The flange face is the sealing surface that comes in contact with a gasket to form a leak-proof seal. There are several types of flange faces, each suited for different applications and pressure ratings.

Common Face Types

1. 盛り上がった顔 (RF)

   • Most common face type

   • Raised ring around the bore

   • Compatible with flat or spiral wound gaskets

   • Found in ASME and EN flanges

2. 平面 (FF)

   • Entire flange face is flat

   • Used in low-pressure systems and with cast iron

   • Gasket must cover the full face

3. リング型ジョイント (RTJ)

   • Grooved face with metal ring gasket

   • 高圧, 高温システム

   • Requires precise machining

4. タング・アンド・グルーブ / 男性と女性

   • Specialized face types for alignment-sensitive systems

   • Often used in heat exchangers

Why Face Type Matters

• Ensures 漏れのないシール プレッシャーの下で

• Affects gasket selection and installation

• Influences assembly time and cost

• Incompatible face types can lead to misalignment or leakage

sasaflange supplies flanges with all major face types, machined to high precision for dependable gasket performance and system reliability.

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Parameter 3: Dimensional Tolerances

What Are Dimensional Tolerances?

Dimensional tolerance refers to the allowable deviation from nominal measurements in a flange’s size. これらには以下が含まれます:

• 外径 (の)

• ボルト円直径 (BCD)

• Number and position of bolt holes

• Bore diameter

• Hub dimensions

• 厚さ

• Face height

Standards define acceptable limits for each dimension to ensure flanges from different manufacturers can mate correctly.

Importance of Dimensional Tolerances

• 互換性: Components from different suppliers must fit perfectly

• Sealing integrity: Incorrect bolt alignment can damage gaskets

• 安全性: Mismatched flanges can leak or fail under pressure

• 設置のしやすさ: Precision speeds up alignment and bolting

Dimensional Control in Practice

ササフランジへ, all flanges are CNC machined and go through strict dimensional inspections. Precision tools such as calipers, coordinate measuring machines (三次元測定機), and laser scanners are used to verify:

• Flange OD and thickness

• Bolt hole pitch circle diameter and spacing

• Bore alignment with mating pipe

• Face flatness and perpendicularity

All dimensions conform to tolerances outlined in ASME B16.5, ASME B16.47, とEN 1092-1.

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Interrelation Between the Parameters

These three parameters are interdependent. 例えば:

• A higher 圧力定格 often requires a 上げられた顔 または RTJフェイス to handle gasket stress.

• Tighter 寸法公差 are critical for RTJ flanges to ensure a perfect metal-to-metal seal.

• Different face types require specific bolt circle dimensions and gasket sizes.

Failing to consider one parameter can undermine the performance of the other two. That’s why professional suppliers like sasaflange emphasize holistic flange engineering rather than treating each factor in isolation.

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How to Specify a Flange Correctly

When sourcing a flange, it is essential to specify all three parameters accurately:

1. 圧力定格: Based on system pressure and temperature

2. 顔のタイプ: Depending on gasket type and sealing performance required

3. Dimensional standard and tolerance: To ensure compatibility with existing equipment

Example specification:

• ASME B16.5, クラス 300, 4-inch Weld Neck Flange, RF Face, ステンレス鋼316L

sasaflange helps customers define these parameters during the design and procurement process to ensure smooth project execution.

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結論

Understanding the three most important parameters in flange standards—圧力定格, 顔のタイプ, そして 寸法公差—is critical for safe, 効率的, and reliable piping system operation.

These parameters not only ensure that flanges perform under pressure but also allow for compatibility between components sourced from different manufacturers and countries.

sasaflange specializes in the production and supply of standard and custom stainless steel flanges. 厳格な品質管理のもと、, 寸法精度, and full documentation support, we help clients meet the toughest project requirements across the globe.