Sanitary Clamp Fittings - Ensure Sterile Fluid Pathways
Mitigate cross-contamination risks and ensure aseptic fluid path integrity. Our Sanitary Clamp Fittings are engineered specifically for critical Bio-Pharm and F&B processing lines. Manufactured from fully traceable ASTM A270 316L Stainless Steel, these components feature strictly controlled internal surface finishes (Ra) to minimize bio-burden adhesion and biofilm formation.
Designed to withstand aggressive Clean-in-Place (CIP) chemicals and Steam-in-Place (SIP) thermal cycling, these fittings prevent “dead legs” and ensure cleanability. Precision machining guarantees dimensional concentricity, preventing gasket intrusion and ensuring compliance with FDA 21 CFR and cGMP mandates.
Types of Sanitary Clamp Fittings We Supply
Sanitary Fittings
Sanitary Clamp Fittings
Sanitary Threaded
Sanitary Weld
Components
Hygiene & Material Science
Why 316L is the Bioprocessing Standard: In high-purity applications, material passivation is critical. We utilize 316L Stainless Steel due to its Molybdenum content (2-3%), which significantly enhances resistance to pitting corrosion and chloride-induced stress corrosion cracking—common failure modes in saline buffer loops.
The Physics of Cleanability (Ra Values): “Smooth” is not a specification. We strictly control Roughness Average (Ra).
SF1 (Mechanical Polish): Ra ≤ 0.5µm. Removes macro-imperfections, suitable for most F&B and secondary pharma loops.
SF4 (Electropolished): Ra ≤ 0.38µm. An electrochemical process that removes surface peaks and enriches the passive chromium oxide layer. This is essential for WFI (Water for Injection) systems to minimize particulate generation and accelerate dry-down.
What is Sanitary Clamp Fittings?
Sanitary Clamp Fittings (commonly referred to as Tri-Clamp® fittings) are specialized piping connections designed specifically for biopharmaceutical and food & beverage industries. Unlike industrial flanges, they utilize a threadless, crevice-free design consisting of two mating ferrules, a hygienic gasket, and a clamp. This assembly creates a flush, aseptic seal that eliminates bacterial harborage sites (“dead legs”) and allows for validated Clean-in-Place (CIP) and Steam-in-Place (SIP) processes.
Why Engineers Specify Sanitary Clamps Over Flanges?
In sterile processing lines, standard NPT threads or ANSI flanges are contamination risks because they create crevices where bacteria can colonize (bio-burden). Sanitary clamp fittings are engineered to solve this:
Aseptic Integrity: The gasket aligns perfectly with the pipe ID, ensuring laminar flow and preventing product accumulation.
Surface Finish: Manufactured from 316L Stainless Steel, the internal surfaces are polished to Ra < 0.5µm (ASME BPE SF1) or electropolished to ensure no microscopic pits exist for bacteria to hide.
Maintenance Efficiency: They can be disassembled by hand (tool-free) for inspection or gasket replacement, which is critical for frequent cleaning cycles.
Common Names: Tri-Clamp, Tri-Clover, Hygienic Ferrule.
Key Standards: ASME BPE (Biopharma), 3-A 63-04 (Food/Dairy).
Material: ASTM A270 316L Stainless Steel.
Connection Style: Genderless mating ferrules secured by a heavy-duty or high-pressure clamp.
Pressure Rating: Typically up to 250 PSI (dependent on size and clamp type).
Dimension Table
Essential for preventing ordering errors, specifically regarding the 1.0″ vs 1.5″ flange confusion.
Ferrule Dimensions (ASTM A270 / ASME BPE)
| Tube OD Size | Flange OD (A) | Tube ID (B) | Compatible Clamp Size |
| 0.50″ | 0.984″ | 0.370″ | 0.5″ – 0.75″ Series |
| 0.75″ | 0.984″ | 0.620″ | 0.5″ – 0.75″ Series |
| 1.00″ | 1.984″ | 0.870″ | 1.5″ Series |
| 1.50″ | 1.984″ | 1.370″ | 1.5″ Series |
| 2.00″ | 2.516″ | 1.870″ | 2.0″ Series |
| 3.00″ | 3.579″ | 2.870″ | 3.0″ Series |
| 4.00″ | 4.682″ | 3.834″ | 4.0″ Series |
Assembly & Maintenance Guide
Best Practices for System Integrity:
Gasket Intrusion Control: Over-tightening clamps causes the gasket to protrude into the pipe ID, creating a dam that traps bacteria.
Protocol: Use a calibrated torque wrench (typically 25-50 in-lbs for standard elastomers) or specific “stop-nut” clamps to ensure controlled compression.
Thermal Cycling & Creep: Polytetrafluoroethylene (PTFE) gaskets are prone to “cold flow.” After the initial SIP cycle (121°C), retightening is often required to prevent leaks.
Solution: For high-cycling lines, consider Live-Loaded Clamps or PTFE/EPDM envelope gaskets to maintain seal pressure.
Visual Inspection: Regularly inspect ferrules for nicks or scratches on the gasket sealing face. Even microscopic damage can compromise the hygienic seal and lead to batch contamination.
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FAQ
How do I measure a Tri-Clamp fitting size?
Sanitary fittings are sized by the Tube Outer Diameter (OD), not the flange size. For example, a “1.5-inch fitting” fits a 1.5-inch tube, but has a flange OD of 1.984″. Always measure the ID of the tube to confirm the correct size, especially for 1″ and 1.5″ fittings which share the same flange dimension.
What is the difference between BPE and Standard 3-A fittings?
ASME BPE (Bioprocessing Equipment) fittings generally require tighter tolerances, specific sulfur content ranges in the 316L steel for weldability, and strict documentation (MTRs) compared to standard 3-A food-grade fittings. BPE is the standard for injectable drugs and biotech; 3-A is sufficient for dairy and food.
Can these fittings be used for vacuum applications?
Yes. Tri-Clamp connections are rated for high vacuum, provided the correct gasket is used. We recommend vacuum-rated elastomers or metal-detectable gaskets to ensure the seal does not deform or “suck in” under negative pressure.