Aseptic Flange Fitting Configuration And Connection Guide

A DIN 11864 aseptic flange connection prevents contamination by eliminating dead spaces and crevices where bacteria can grow. The design uses a defined O-ring preload, a precision-machined retaining groove, and metallic flange centering to create a flush, crevice-free seal. This geometry ensures that no product residues accumulate, enabling effective CIP and SIP cleaning. By removing microscopic gaps, these connections protect product integrity in pharmaceutical, biotech, and food processing.

How does a DIN 11864 connection prevent contamination

1. A defined O-ring preload ensures consistent sealing force under pressure and temperature changes.

2. A precision groove centers the O-ring automatically and prevents displacement during assembly.

3. Metal-to-metal flange contact acts as a positive stop, limiting O-ring compression and preventing damage.

4. Metallic centering eliminates side loads that could create gaps between sealing elements.

Common Design Pitfalls – Why and How to Avoid

• ✅ Wrong Form variant → Form A and Form B have different groove profiles and are not interchangeable. → Specify Form A for standard pharmaceutical applications.

• ⚠️ Incorrect O-ring material → EPDM serves -40°C to +90°C; FEP handles higher temperatures. → Select based on process temperature and chemical compatibility.

• 📊 Misaligned welding ends → Creates stress points that compromise seal integrity. → Extended welding ends support orbital welding for seamless integration.

• ⏳ Ignoring surface finish → Internal surfaces must meet Ra < 0.8 μm (H3) or Ra < 0.4 μm (H4). → Specify based on industry requirement.

DIN 11864 Standards Overview – Connection Types

DIN 11864-1 (Screwed Union): Threaded nut with O-ring seal, metallic centering. A din 11864 1 connection is standard for frequent disconnection and sampling points.

DIN 11864-2 (Flanged): Bolted flange with O-ring groove. A din 11864 2 flange suits high-pressure applications (up to 40 bar) and large diameters.

DIN 11864-3 (Clamp): Quick-connect clamp with O-ring seal for frequent assembly/disassembly in CIP/SIP systems.

Form A vs Form B Configurations

DIN 11864-1 Form A is the standard assembly with threaded ferrule, liner, and union nut. The O-ring groove is machined directly into the liner, and metallic centering ensures proper alignment. A din 11864 1 form a connection is the standard choice for pharmaceutical applications requiring frequent disassembly.

DIN 11864-1 Form B uses a liner with a separate retaining ring for the O-ring, providing an alternative sealing profile.

Important: Form A and Form B are not interchangeable. A din 11864 1a (Form A) connection is specified for most sterile applications.

Materials and Surface Finish

Body Material:

• 1.4404 (316L) or 1.4435 (316L) stainless steel

• Delta ferrite < 1% for optimal weldability and corrosion resistance

Surface Finish:

• Standard hygienic (H3): Ra < 0.8 μm

• Pharmaceutical (H4): Ra < 0.4 μm (ASME BPE SF4 compliant)

Seal Materials:

• EPDM: -40°C to +90°C, short-term +140°C. FDA and USP Class VI compliant.

• FEP-encapsulated: -60°C to +160°C, short-term +205°C.

Pressure and Temperature Ratings

Pressures based on DIN 11864-1 at room temperature. Derate above 100°C.

Applications

Pharmaceutical: WFI systems, pure steam, sterile filling. 316L, Ra < 0.4 μm (H4), EPDM/FEP.

Biotech: Cell culture, fermentation, chromatography. 316L, Ra < 0.8 μm (H3), FDA EPDM.

Food: High-purity dairy, beverage, aseptic packaging. 316L, Ra < 0.8 μm (H3), FDA EPDM.

Aseptic Connection Guide

A din 11864 aseptic flange connection achieves zero-crevice sealing through O-ring preload, precision groove, and metallic centering. For pharmaceutical: DIN 11864-1 Form A, 316L, Ra < 0.4 μm (H4), EPDM/FEP. Form A and Form B are not interchangeable—specify Form A for standard sterile service. A din 11864 1 union suits frequent disconnection. A din 11864 2 flange suits high-pressure applications. A din 11864 1 form a connection is the standard pharmaceutical assembly. A din 11864 1a (Form A) is specified for most sterile applications. The crevice-free design prevents biofilm formation and ensures full CIP/SIP compatibility.

DIN 11864-2 Aseptic Flange Connection

• DIN 11864-2 is a gap-free connection that has been specially designed with sterile applications in mind.
• The DIN11864-2 stainless fittings are available in practically all sizes and standard configurations. With these flanges means the process conditions are optimized inside for sterility and cleaning processes whilst ensuring the highest safety to the environment.
• All DIN11864-2 aseptic stainless flanges have a smaller outer diameter and are very compact. The design of these aseptic stainless unions incorporates the use of a standard dimension o-ring which gives the flexibility of material choice.

Product Description

Product Parameter