Sanitary Weld Reducers (Concentric & Eccentric) – SS304 / SS316L
In hygienic process lines, the transition between pipe diameters is a critical control point for fluid dynamics and sterility. Improper reduction leads to “dead legs,” turbulence, and air entrapment, which compromise CIP (Clean-in-Place) effectiveness. Our Sanitary Weld Reducers are engineered via cold forming to ensure a smooth, crevice-free internal transition. Designed for critical food grade and bioprocess applications, these fittings facilitate complete drainage and maintain line pressure without creating bacterial harborage sites. Whether mitigating pump cavitation with eccentric reducers or managing vertical flow with concentric profiles, we provide verifiable compliance for high-purity loops.
- Material: Traceable SS316L (1.4404) or SS304.
- Geometry: True Tangential design for orbital welding.
- Finish: ID Ra < 0.4μm (15μin) Electropolished.
- Hygiene: Eliminates pooling and cross-contamination risks.
- Standards: Exceeds 3A, DIN 11852, ASME BPE.
- Supply: Bulk B2B availability with MTRs.
Technical Specifications
Product Name
Sanitary Butt Weld Reducer (Concentric & Eccentric)
Material Grades
Stainless Steel 304 (1.4301), 316L (1.4404)
Design Standards
3A 63-04, DIN 11852, SMS 3008, ISO 1127, ASME BPE (SF1/SF4)
Wall Thickness
Matches Tubing: 0.065″ (1.65mm), 0.083″ (2.11mm), or Schedule sizes
Forming Method
Cold Pressed / Hydroformed (Seamless construction)
Size Range
1/2″ x 1/4″ up to 12″ x 10″ (DN10 – DN300)
Surface Finish (ID)
Standard: Ra ≤ 0.8μm (32μin); BPE High Purity: Ra ≤ 0.38μm (15μin)
Heat Treatment
Solution Annealed & Water Quenched
Combating Pump Cavitation (Eccentric Application)
Pain Point: Installing a concentric reducer at a horizontal pump suction inlet creates an air pocket at the top of the pipe. This trapped air enters the impeller, causing cavitation, noise, and premature pump failure.
Solution: Our Sanitary Eccentric Reducers are designed for “Flat-Top” installation. This alignment forces air to pass through the system immediately, protecting expensive pumps and flow meters in brewery and dairy applications.
Optimized for Orbital Welding
Pain Point: Many generic reducers have short tangents (straight ends) or inconsistent wall thickness, leading to weld “rollout” or lack of fusion during automatic welding.
Solution: We adhere to strict dimensional tolerances with extended tangents. For ASME BPE orders, we control sulfur content (0.005%–0.017%) to ensure consistent weld bead penetration and width during autogenous orbital welding.
Surface Integrity & CIP Efficiency
Pain Point: Rough internal surfaces in reducers increase drag and retain product residue, requiring longer CIP cycles and more chemical usage.
Solution: With options for Mirror Polished or Electropolished interiors (Ra < 0.4μm), our reducers minimize surface tension. This ensures rapid cleaning cycles and reduces the risk of biofilm formation in pharmaceutical grade loops.
Typical dimensions for procurement planning. Custom lengths available for OEM orders.
| Large OD (D1) | Small OD (D2) | Wall Thickness (t) | Overall Length (L) |
| 1.5″ (38.1mm) | 1.0″ (25.4mm) | 0.065″ (1.65mm) | 2.50″ (63.5mm) |
| 2.0″ (50.8mm) | 1.0″ (25.4mm) | 0.065″ (1.65mm) | 4.50″ (114.3mm) |
| 2.0″ (50.8mm) | 1.5″ (38.1mm) | 0.065″ (1.65mm) | 2.50″ (63.5mm) |
| 2.5″ (63.5mm) | 2.0″ (50.8mm) | 0.065″ (1.65mm) | 2.625″ (66.7mm) |
| 3.0″ (76.2mm) | 2.0″ (50.8mm) | 0.065″ (1.65mm) | 4.50″ (114.3mm) |
| 4.0″ (101.6mm) | 3.0″ (76.2mm) | 0.083″ (2.11mm) | 4.625″ (117.5mm) |
Weld Preparation & Facing: Ensure the reducer and connecting tube faces are square-cut and deburred. Use a facing tool to achieve zero-gap fit-up. Clean the weld zone with isopropyl alcohol to remove any oils from the forming process.
Purge Gas Protocol: For Stainless Steel Sanitary Reducers, internal back-purging with high-purity Argon (99.99%) is non-negotiable. Maintain purge until the weld zone cools below 300°C to prevent heat tint (oxidation), which lowers corrosion resistance.
Installation Orientation:
Drainage Lines: Install Eccentric Reducers “Flat Side Down” to ensure no liquid pools in the reducer during system draining.
Vertical Lines: Use Concentric Reducers to maintain symmetrical flow velocity and prevent vibration.
Post-Weld Passivation: After welding, the system should undergo a citric or nitric acid passivation cycle (ASTM A967) to remove free iron and restore the passive chromium oxide layer.
Related Products
FAQ
When should I use a Sanitary Eccentric Reducer versus a Concentric Reducer?
Use Sanitary Eccentric Reducers on horizontal pipelines to prevent air pockets (flat-side up for pumps) or ensure full drainage (flat-side down). Use Concentric Reducers on vertical flow lines where air entrapment is not an issue and symmetrical flow is required to maintain pressure stability.
What is the difference between 3A and ASME BPE reducers?
3A standards focus primarily on cleanability for food and dairy, whereas ASME BPE (Bioprocessing Equipment) enforces stricter criteria for the pharmaceutical industry, including specific sulfur content ranges for welding, documented surface finish (Ra) verification, and 100% borescope inspection.
Do you provide Material Test Reports (MTRs) for these reducers?
Yes, as a professional B2B manufacturer, we provide EN 10204 3.1 Material Test Reports with every shipment. This document validates the chemical composition (heat number), mechanical properties, and compliance with standards like ASTM A270 or DIN 11850.
Can these reducers be used for orbital welding?
Yes, our Butt Weld Sanitary Reducers are manufactured with extended tangents (straight ends) specifically to accommodate orbital weld heads. This ensures the clamp head clears the tapered section of the reducer for a precise, autogenous weld.
What surface finish is recommended for WFI (Water for Injection) systems?
For WFI and high-purity bioprocess applications, we recommend an ASME BPE SF4 finish, which is an Electropolished surface with a maximum roughness of Ra 15μin (0.38μm). This finish removes microscopic peaks where bacteria can hide.