Titanium Flange Face Types (RF/FF/RJ): How to Choose for Chlor-Alkali Service Conditions?

In the complex pipeline networks of the chlor-alkali industry, flanges are the "joints" connecting various equipment, and the flange face is the "mating surface" of these joints. The selection of its type directly determines whether the pipeline can maintain a tight seal long-term under the high temperature, high pressure, and highly corrosive chlor-alkali media, preventing "leakage, spillage, dripping, and loss."

Feeling confused about common face types like RF, FF, and RJ? Li Hua Titanium simplifies this complexity, providing a selection guide tailored for chlor-alkali service conditions.

First, let's quickly understand the basic profiles of these three main characters.

• Visual: A raised, ring-shaped platform on the flange face, about 2-4mm high. This is the most common and widely used type.

• Sealing Principle: The gasket, sandwiched between two RF flanges, is compressed and deforms within the confined space of the raised face, filling micro-imperfections to achieve a seal.

• Visual: The sealing surface is flush with the entire flange face, with no raised area.

• Sealing Principle: Typically used with a full-face soft gasket (e.g., rubber). Sealing is achieved by compressing over a large area. It is primarily suitable for low-pressure applications.

• Visual: A machined circular, trapezoidal groove on the flange face, appearing very precise.

• Sealing Principle: Used with a metal oval or octagonal ring gasket. When bolts are tightened, the rigid ring gasket is embedded and locked into the groove, forming a robust metal-to-metal seal that is extremely resistant to blowout.

Understanding the basic characteristics, let's see how they perform on the specific battlefield of the chlor-alkali industry.

• Advantages: High versatility, low cost, easy assembly/disassembly, simple gasket replacement.

• Disadvantages: Sealing performance not as high as RJ; gasket is susceptible to blowout risk.

• Recommended Chlor-Alkali Applications: The preferred choice for most atmospheric, low-to-medium pressure (PN16/25), and ambient temperature services. E.g.:

  • Atmospheric brine pipelines

  • Cooling water systems

  • Mild alkaline solution pipelines with low corrosivity

• Advantages: Low cost, easy to machine.

• Disadvantages: Very low sealing pressure capability, high bolt load required.

• Recommended Chlor-Alkali Applications: Only suitable for very low pressure (below PN6), ambient temperature, and non-hazardous media services. Rarely used in the main chlor-alkali process.

• Advantages: Excellent sealing integrity, resistant to high pressure, high temperature, cyclic loading, and vibration; gasket cannot blow out.

• Disadvantages: High cost, requires extremely high machining precision, strict alignment required during assembly/disassembly, sealing surface is easily damaged.

• Recommended Chlor-Alkali Applications: The unrivaled choice for severe service conditions:

  • Inlet/outlet connections of high-temperature, high-pressure reactors

  • Pipelines handling highly toxic, explosive media (e.g., high-pressure chlorine gas, hydrogen)

  • Equipment connections subject to thermal cycling or severe vibration

How to make the final choice for your project? Please follow these principles:

• Consider Pressure:

  • Low Pressure → Choose RF: Cost-effective and perfectly adequate.

  • Medium/High Pressure → Must Choose RJ: Safety first, eliminate leakage risks.

• Consider Media:

  • General Corrosive Media → Choose RF: Performs well with PTFEnvelope gaskets, flexible graphite composite gaskets, etc.

  • Highly Toxic, Harmful, Flammable, Explosive Media → Strongly Recommend RJ: The near-absolute seal provided by the metal ring gasket is your most critical safety barrier.

• Consider Cost & Maintenance:

  • Limited Budget, Emphasizing Ease of Maintenance → Choose RF.

  • Prioritizing Lifecycle Safety, Initial Cost Less Critical → Choose RJ.

Tip: In the chlor-alkali industry, RF is your reliable "daily workhorse," while RJ is the "special forces" for extreme challenges.

As a professional titanium flange manufacturer, Li Hua Titanium not only helps you choose the right flange face but also ensures its long-term stability in the corrosive chlor-alkali environment.

• Precision Machining: We perform high-precision turning and surface finishing on RF and RJ faces of our titanium flanges, ensuring their smoothness and flatness fully meet or even exceed standard requirements, guaranteeing sealing performance at the source.

• Material Assurance: Titanium's inherent excellent strength and absolute corrosion resistance in chlor-alkali media ensure that the flange face does not develop pits or defects due to corrosion over time, permanently maintaining its sealing integrity.

Choosing a flange is not just selecting a connector; it is choosing a reliable safety barrier for your piping system. In the high-safety-demand field of chlor-alkali, using RF for "standard applications" and RJ for "critical points" is wisdom proven through countless engineering practices.

Li Hua Titanium not only provides high-quality titanium flanges but also offers comprehensive technical consultation, including flange face selection, tailored to your specific service conditions, ensuring every choice you make is precise and correct.