{"id":811,"date":"2026-08-11T06:06:28","date_gmt":"2026-08-11T06:06:28","guid":{"rendered":"https:\/\/www.thonglangsupply.com\/%e0%b8%84%e0%b8%b9%e0%b9%88%e0%b8%a1%e0%b8%b7%e0%b8%ad%e0%b9%80%e0%b8%a5%e0%b8%b7%e0%b8%ad%e0%b8%81%e0%b9%83%e0%b8%8a%e0%b9%89%e0%b8%ab%e0%b8%99%e0%b9%89%e0%b8%b2%e0%b9%81%e0%b8%9b%e0%b8%a5%e0%b8%99\/"},"modified":"2026-09-02T06:28:51","modified_gmt":"2026-09-02T06:28:51","slug":"%e0%b8%84%e0%b8%b9%e0%b9%88%e0%b8%a1%e0%b8%b7%e0%b8%ad%e0%b9%80%e0%b8%a5%e0%b8%b7%e0%b8%ad%e0%b8%81%e0%b9%83%e0%b8%8a%e0%b9%89%e0%b8%ab%e0%b8%99%e0%b9%89%e0%b8%b2%e0%b9%81%e0%b8%9b%e0%b8%a5%e0%b8%99","status":"publish","type":"post","link":"https:\/\/www.thonglangsupply.com\/en\/%e0%b8%84%e0%b8%b9%e0%b9%88%e0%b8%a1%e0%b8%b7%e0%b8%ad%e0%b9%80%e0%b8%a5%e0%b8%b7%e0%b8%ad%e0%b8%81%e0%b9%83%e0%b8%8a%e0%b9%89%e0%b8%ab%e0%b8%99%e0%b9%89%e0%b8%b2%e0%b9%81%e0%b8%9b%e0%b8%a5%e0%b8%99\/","title":{"rendered":"Selection Guide for Carbon Steel and Stainless Steel Flanges (JIS, ANSI, DIN) for Piping Systems"},"content":{"rendered":"\t\t
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Selection Guide for Carbon Steel and Stainless Steel Flanges (JIS, ANSI, DIN) for Piping Systems<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t
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In industrial piping and general engineering, a connector just as crucial as the pipes or valves is the “flange.” If a piping system is compared to blood vessels, flanges are like the joints that reliably connect the entire system, allowing for easy disassembly and ensuring it is safe from leaks.<\/p>\n

However, many novice technicians or contractors may have experienced problems such as purchasing flanges of the wrong size, being unable to fit them to existing valves, or encountering rust and leaks shortly after use. The main cause stems from a lack of understanding regarding materials and pressure standards. This article from Thonglang Supply will guide you through an in-depth understanding of piping systems and flanges in simple terms, enabling you to choose carbon steel and stainless steel flanges accurately, safely, and most cost-effectively.<\/p>\n

1. What is a flange and what is its function in a piping system?<\/h4>\n

A flange is a circular or other-shaped metal plate with a center hole allowing liquid or gas to flow through, surrounded by bolt holes for securing connections between pipe-to-pipe, pipe-to-valve, pipe-to-pump, or attaching to pressure vessels.<\/p>\n

Why use flanges instead of direct welding?
\u25cf Easy disassembly and maintenance: When cleaning, replacing valves, or servicing pumps, simply removing the bolts allows for immediate component removal.
\u25cf High pressure resistance: Flanged connections handle pressure and vibration better than standard threaded connections.
\u25cf Effective force distribution: Helps reduce stress generated at the pipe connection points.<\/p>\n

2. Decoding Flange Standards: How do JIS, ANSI, and DIN differ?<\/h4>\n

One of the most common points of confusion for technicians and buyers is regarding standards and pressure ratings. Because flanges manufactured in different regions have different specifications and bolt hole spacings, selecting the wrong standard will make it impossible to bolt them together.<\/p>\n

The 3 main standards commonly used in Thailand are as follows:<\/p>\n

1. JIS Standard (Japanese Industrial Standards)
\u25cf Key Highlight: A Japanese international standard, most widely used in Thailand and across Asia.
\u25cf Pressure Symbol: Uses the letter “K”, such as 10K, 10K (Slip-On), and 20K.
\u25cf Meaning: The “K” number indicates the approximate pressure rating. For example, JIS 10K means it can withstand a maximum pressure of approximately 10 kilograms-force per square centimeter (10 kgf\/cm\u00b2) or around 10 bar.
\u25cf Applications: General water systems, high-rise buildings, fire protection systems, and general industrial plants.<\/p>\n

2. ANSI \/ ASME Standard (American National Standards Institute)
\u25cf Key Highlight: A United States standard, commonly used in the petrochemical, oil, natural gas industries, and for machinery imported from America.
\u25cf Pressure Symbol: Uses “Class” or “LB”, such as Class 150 (150LB) and Class 300 (300LB).
\u25cf Meaning: The pound number (LB) does not refer directly to PSI pressure, but represents a Pressure Rating Class. For instance, ANSI 150LB can withstand slightly higher pressure than JIS 10K at room temperature.
\u25cf Applications: Oil pipes, gas pipes, high-pressure steam pipes, and heavy chemical applications.<\/p>\n

3. DIN \/ EN Standard (Deutsches Institut f\u00fcr Normung)
\u25cf Key Highlight: German and European standard, commonly used in European machinery, food processing plants, and wastewater treatment systems.
\u25cf Pressure Symbol: Uses “PN” (Pressure Nominal), such as PN10, PN16, and PN40.
\u25cf Meaning: The PN number directly indicates the working pressure in bar; for example, PN16 means it can handle a pressure of 16 bar.
\u25cf Applications: Machinery imported from Europe and high-precision chemical piping systems.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Comparison Table of Popular Flange Standards<\/p>\n\n\n\n\n\n\n\n
Standard<\/strong><\/td>\nCountry \/ Region<\/strong><\/td>\nCommon Pressure Symbols<\/strong><\/td>\nApproximate Equivalent Pressure Rating<\/strong><\/td>\nCommon Applications<\/strong><\/td>\n<\/tr>\n<\/thead>\n
JIS<\/b><\/span><\/td>\nJapan \/ Asia<\/span><\/td>\nJIS 5K, 10K, 20K<\/span><\/td>\n10K approx. 10 Bar<\/span><\/td>\nWater supply systems, high-rise buildings, general factories<\/span><\/td>\n<\/tr>\n
ANSI<\/b><\/span><\/td>\nUnited States<\/span><\/td>\n150LB, 300LB, 600LB<\/span><\/td>\n150LB approx. 16-19 Bar (depending on temperature)<\/span><\/td>\nPetrochemical, oil, natural gas<\/span><\/td>\n<\/tr>\n
DIN<\/b><\/span><\/td>\nEurope<\/span><\/td>\nPN6, PN10, PN16, PN40<\/span><\/td>\nPN16 = 16 Bar<\/span><\/td>\nEuropean machinery, chemical plants, food industry<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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3. Deep Dive into Material Selection: Carbon Steel Flanges vs. Stainless Steel Flanges<\/h4>\n

Material selection is the heart of piping system and flange design because it directly impacts lifespan, corrosion issues, and safety.<\/p>\n

[Popular Carbon Steel and Stainless Steel Types]
\u251c\u2500\u2500 1. Carbon Steel<\/strong>
\u2502 \u2514\u2500\u2500 Grade SS400 \/ A105 -> Suitable for water, air, and general oil
\u2514\u2500\u2500 2. Stainless Steel<\/strong>
\u251c\u2500\u2500 SUS304 -> Rust-resistant, water-resistant, resistant to mild chemicals (Food\/Drinking water applications)
\u2514\u2500\u2500 SUS316 \/ 316L -> Resistant to acids, alkalis, concentrated chemicals, and marine salt spray<\/p>\n

Carbon Steel Flange<\/strong><\/p>\n

Carbon steel flanges are manufactured from ductile iron or carbon steel (such as grades SS400, A105). They are the most popular type of flange due to their economical price and high strength.<\/p>\n

\u25cf Key Highlights:
\u25cb Cost-effective with excellent resistance to impacts and pressure.
\u25cb Superior high-temperature resistance.
\u25cb Easy to weld securely to steel pipes.
\u25cf Limitations: Prone to rust if exposed to moisture, water, or chemicals; therefore, they require anti-rust painting, galvanization, or powder coating.
\u25cf Suitable Applications: Chilled water pipe systems, compressed air lines, fire protection lines, fuel lines, and general steam lines.<\/p>\n

Stainless Steel Flange<\/strong><\/p>\n

Stainless steel flanges are manufactured from high-quality stainless steel containing chromium and nickel, which help form a protective surface film preventing easy rust formation. Commonly used types include SUS304 and SUS316\/316L.<\/p>\n

\u25cf Key Highlights:
\u25cb High corrosion and rust resistance: Long service life even when exposed to moisture or chemicals.
\u25cb Clean and Hygienic: No peeling, leaving no rust stains to contaminate fluids.
\u25cb Chemical and heat resistance: Can handle acids, alkalis, and temperature fluctuations well.
\u25cf In-depth Stainless Steel Grades:
\u25cb SUS304: Standard grade with good rust resistance. Suitable for drinking water, food, beverages, and diluted chemicals.
\u25cb SUS316 \/ 316L: Formulated with added Molybdenum, providing excellent resistance to salt spray, seawater, concentrated acids, and chlorine.
\u25cf Suitable Applications: Food and pharmaceutical manufacturing plants, chemical plants, wastewater treatment systems, coastal\/offshore applications, and piping systems requiring high levels of hygiene.<\/p>\n

\u00a04. Selection Factors: Heat Resistance, Chemical Resistance, and Environment<\/h4>\n

To make the most effective material and standard selections for your flange, consider these 3 key factors:<\/p>\n

1) Fluid Medium
\u25cf For clean water, compressed air, oil: Carbon steel flanges can be selected to save budget.
\u25cf For drinking water, food, milk, pharmaceuticals: SUS304 stainless steel flanges should be used for cleanliness.
\u25cf For concentrated acids, corrosive chemicals, seawater: SUS316\/316L stainless steel flanges must be chosen.<\/p>\n

2) Working Temperature & Pressure**
\u25cf Pressure: Select a pressure rating (JIS 10K, ANSI 150LB, DIN PN16) at least 20-30% higher than the maximum system pressure to accommodate potential water hammer phenomena.
\u25cf Temperature: If the system operates at very high temperatures (such as steam pipes exceeding 200\u00b0C), the allowable pressure rating of the flange decreases proportionally. A higher Class standard must be selected, along with a compatible heat-resistant gasket.<\/p>\n

3) External Environment
\u25cf Indoor \/ dry building installation: Carbon steel flanges with anti-rust coating are sufficient.
\u25cf Outdoor installation \/ exposure to rain, acidic gas environments, or coastal areas:** Stainless steel flanges should be selected to prevent external pitting corrosion and rust.<\/p>\n

5. Summary: Techniques for Cost-Effective and Safe Flange Selection<\/h4>\n

Selecting a flange that fits a piping system involves more than just checking nominal size in inches; all components must be thoroughly verified:<\/p>\n

1. **Check the original equipment standard:** Verify what standard the existing valves or machinery use (JIS, ANSI, or DIN) to select matching flanges.
2. **Choose the right material for the job:** Carbon steel flanges are suitable for general, budget-focused applications, while stainless steel flanges are suited for corrosion-resistant and hygienic applications.
3. **Don’t forget gaskets and bolts:** Always select gasket materials (Rubber, EPDM, Teflon, Graphite) and flange bolt grades that match the chemical and heat resistance requirements of the flange.<\/p>\n

If you are looking for high-quality carbon steel or stainless steel flanges that meet international standards across all pressure ratings (JIS, ANSI, DIN), supported by an expert team ready to provide advice, you can view products and inquire further at [www.thonglangsupply.com](https:\/\/www.google.com\/search?q=https%3A%2F%2Fwww.thonglangsupply.com) \u2014 the center for industrial piping systems, valves, and flanges trusted by technicians and contractors.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"

Selection Guide for Carbon Steel and Stainless Steel Flanges (JIS, ANSI, DIN) for Piping Systems In industrial piping and general engineering, a connector just as crucial as the pipes or valves is the “flange.” If a piping system is compared to blood vessels, flanges are like the joints that reliably connect the entire system, allowing […]<\/p>\n","protected":false},"author":1,"featured_media":784,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[17],"tags":[],"class_list":["post-811","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"_links":{"self":[{"href":"https:\/\/www.thonglangsupply.com\/en\/wp-json\/wp\/v2\/posts\/811","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.thonglangsupply.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.thonglangsupply.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.thonglangsupply.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.thonglangsupply.com\/en\/wp-json\/wp\/v2\/comments?post=811"}],"version-history":[{"count":8,"href":"https:\/\/www.thonglangsupply.com\/en\/wp-json\/wp\/v2\/posts\/811\/revisions"}],"predecessor-version":[{"id":826,"href":"https:\/\/www.thonglangsupply.com\/en\/wp-json\/wp\/v2\/posts\/811\/revisions\/826"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.thonglangsupply.com\/en\/wp-json\/wp\/v2\/media\/784"}],"wp:attachment":[{"href":"https:\/\/www.thonglangsupply.com\/en\/wp-json\/wp\/v2\/media?parent=811"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.thonglangsupply.com\/en\/wp-json\/wp\/v2\/categories?post=811"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.thonglangsupply.com\/en\/wp-json\/wp\/v2\/tags?post=811"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}