In marine and industrial environments, selecting the right flange standard is critical to ensuring safety, reliability, and seamless integration between piping and valves. Among the most widely used standards in Asia, JIS (Japanese Industrial Standards) flanges play a vital role in shipbuilding, oil and gas, petrochemical, and general industrial systems.

As a leading Singapore-based stockist and distributor of marine and industrial valves, Aik Soon Hardware Pte Ltd supplies a wide range of JIS flanges that meet rigorous quality requirements. This article explores the common JIS flange standards, the differences between them, and how to choose the right standard for your application.

What Are JIS Flanges?

JIS flanges are designed according to the Japanese Industrial Standards (JIS), which specify dimensions, pressure ratings, and material requirements. They are commonly found across Asia—especially in shipbuilding and marine engineering—making them essential for global supply chains that interface with Japanese or regional equipment.

Unlike other standards such as ANSI/ASME (American) or DIN/EN (European), JIS flanges are unique in their dimensions, pressure ratings, and bolt hole configurations. Using the wrong flange standard can result in costly mismatches, safety risks, and downtime.

Common JIS Flange Standards

The most widely used JIS flange standards include:

1. JIS B2220 – Steel Pipe Flanges

   • Covers the dimensions and types of flanges for pipes, valves, and fittings.

   • Pressure ratings are usually 5K, 10K, 16K, 20K, and 30K, with 10K and 16K being most common in marine applications.

   • Found extensively in ship piping systems, including ballast water, cooling, and cargo pipelines.

2. JIS B2210 – Flanges for Pressure Vessels

   • Specifically designed for pressure vessels rather than general piping.

   • Ensures compliance with high-pressure systems found in refineries and petrochemical plants.

3. JIS B2238 / JIS B2239 – Cast Iron Pipe Flanges

   • These apply to cast iron piping systems, often used in non-critical water services.

Differences Between JIS Flange Standards

When evaluating JIS flanges, it’s important to consider how they differ from one another:

• Pressure Classifications

  • JIS flanges use “K” to indicate pressure rating (e.g., 10K = 10 kg/cm² ≈ 142 psi).

  • This differs from ANSI “Class” or DIN “PN” ratings.

• Bolt Hole Arrangement & Dimensions

  • JIS flanges have different bolt circle diameters (PCD) and hole sizes compared to ANSI or DIN.

  • For example, a JIS 10K DN200 flange will not match an ANSI 150 DN200 flange.

• Regional Compatibility

  • JIS standards are most commonly used in Asia and Japan-built vessels/equipment, whereas ANSI and DIN dominate Western markets.

• Application Specificity

  • JIS B2220 (general piping) vs. JIS B2210 (pressure vessels).

  • Selecting the wrong type could lead to serious engineering or safety issues.

How to Pick the Right JIS Flange Standard

Choosing the correct flange standard depends on several factors:

1. Identify the System Design Standard

   • Check whether your piping/valve system is built to JIS, ANSI, or DIN/EN standards. Mixing standards can cause leaks or equipment failure.

2. Match Pressure Rating (K Class)

   • For marine pipelines: 5K or 10K are often used for low-pressure services.

   • For engine cooling, steam, or oil systems: 16K or higher is required.

3. Confirm Size and Bolt Pattern

   • Always verify nominal diameter (DN), pitch circle diameter (PCD), and bolt holes to avoid mismatch during installation.

4. Consider Material Selection

   • Carbon steel, stainless steel, and cast iron JIS flanges are available depending on fluid type and corrosion resistance needs.

5. Work with a Trusted Supplier

   • Partnering with a reliable distributor like Aik Soon Hardware ensures quality, compliance, and quick access to a wide range of JIS flanges in Singapore and across Asia.

Conclusion

JIS flange standards play an essential role in ensuring safe and reliable piping and valve connections in marine and industrial environments. By understanding the common JIS flange standards (B2220, B2210, B2238/2239), knowing the differences from other global standards, and carefully selecting the right flange for your system, you can avoid costly downtime and ensure compliance.

At Aik Soon Hardware Pte Ltd, we provide a full range of JIS-standard flanges and valves, backed by technical expertise and decades of experience serving the marine, offshore, oil & gas, and industrial sectors.