Engineered Flanged Polyether-TPU Flexible Sleeves: Standard DIN/ANSI Sizes & Custom Irregular Configurations
100% Crevice-Free, Vibration-Resistant, Dust-Tight Flexible Connectors for Food, Pharmaceutical, and Chemical Bulk Solids
Connecting vibrating hoppers, loss-in-weight feeders, screener discharges, and rotary airlocks requires flexible joints that withstand continuous mechanical oscillation without tearing, leaking fugitive dust, or harboring microbial contamination.
SOSHH® Flanged Polyether-TPU Flexible Sleeves are thermo-fusion welded to eliminate traditional stitched seams, glued joints, and hose-clamp leakage. Available in both standard circular flange dimensions and fully bespoke irregular geometries (square-to-round, conical, rectangular, and offset transitions), our sleeves provide superior tensile durability, optical clarity, and optional ATEX-compliant static dissipation for combustible organic powders like coffee, starches, and battery materials.
SOSHH® DN200 custom flanged TPU flexible sleeve featuring 1.0mm food-grade polyether polyurethane and integrated thermo-welded soft flanges.
Standard Size Matrix vs. Custom Irregular Shape Capabilities
Whether retrofitting existing DIN/ANSI counter-flanges or engineering custom transitions for bespoke OEM machinery, our laser-cut and thermo-welded manufacturing platform supports virtually any geometry without expensive molding tooling.
1. Common Standard Flange Specifications
| Standard Size | Inner Diameter (ID) | Outer Diameter (OD) | Bolt Circle (PCD) | Hole Configuration | Typical Installed Height |
| DN100 (4") | 100 mm | 180 mm | 145 mm | 4 × Ø14 mm (for M12) | 100 mm – 200 mm |
| DN150 (6") | 150 mm | 240 mm | 200 mm | 8 × Ø14 mm (for M12) | 100 mm – 250 mm |
| DN200 (8") | 200 mm | 280 mm | 240 mm | 8 × Ø14 mm (for M12) | 116 mm – 300 mm |
| DN250 (10") | 250 mm | 340 mm | 295 mm | 8 / 12 × Ø18 mm (for M16) | 120 mm – 350 mm |
| DN300 (12") | 300 mm | 395 mm | 350 mm | 12 × Ø18 mm (for M16) | 150 mm – 400 mm |
| DN400 (16") | 400 mm | 505 mm | 460 mm | 16 × Ø18 mm (for M16) | 150 mm – 500 mm |
Custom hole patterns available for ANSI 150#, JIS 10K, Jacob modular tubing, and non-standard equipment PCDs.
2. Bespoke Irregular Geometries
- Square-to-Round & Rectangular-to-Round Transitions: Connects square vibrating bin discharges to cylindrical rotary valves or dosing screws.
- Conical & Concentric/Eccentric Reducers: Facilitates smooth gravity flow between differing inlet/outlet diameters while preventing flow segregation and shelf accumulation.
- Axially Offset & Angled Sleeves: Compensates for misaligned pipework or multi-axis equipment thermal expansion without creating localized stress folds.
- Multi-Fold Accordion Bellows: Designed for ultra-high vertical stroke applications, weighing scales, and loss-in-weight feeders requiring zero lateral force resistance.
| Profile Type | Geometric Features | Typical Application |
| Square-to-Round | Flat square flange top, circular cylindrical base | Vibrating hopper outlet to rotary airlock feeder |
| Conical Reducer | Tapered conical wall transition | Cyclone receiver to storage buffer bin |
| Eccentric Offset | Asymmetrical centerline compensation | Misaligned gravity drop chute retrofit |
| Rectangular Flanged | 4-side perimeter bolting configuration | Linear vibrating screen discharge spout |
Material Selection: Ultra-Clear Food Grade vs. Permanent Anti-Static
Handling organic, combustible powders—such as roasted/instant coffee grounds, milk powders, cocoa, and pharmaceutical excipients—demands strict attention to static buildup and cleanability.
1. Ultra-Clear Food-Grade Polyether-TPU
- Optical Transparency (>92%): Allows operators to visually monitor powder flow rates, detect bridging, and verify clean-in-place (CIP) washdown status without stopping production.
- Hydrolysis & Microbial Resistance: Ether-based backbone prevents hardening, yellowing, or bacterial harboring in humid washdown environments.
- Compliance: Exceeds FDA 21 CFR 177.2600 and EU EC 1935/2004 food-contact standards.
2. Permanent Static-Dissipative TPU
- Eliminating Coffee Powder Wall Cling: Fine coffee dust accumulates significant triboelectric surface charges during free fall. Static-dissipative TPU (10^8 to 10^10 Ohm surface resistivity) bleeds charges directly to grounded metal flanges, keeping the inner bore clean and preventing dark, rancid oil crust accumulation.
- ATEX Dust Explosion Safety (Zones 20, 21, 22): Certified for use in combustible dust environments where fine organic dust clouds present an ignition risk (MIE < 30 mJ). Conductive properties are permanently embedded into the polymer matrix—no surface coatings that can rub off or contaminate food batches.
Engineering Advantages Over Conventional Clamp-On Sleeves
| Feature | Clamped Rubber / Stitched Sleeves | SOSHH® Flanged Polyether-TPU |
| Sanitary Sealing | Stitched holes & clamp folds harbor bacteria | 100% Seamless thermo-welded internal bore |
| Dust Integrity | Worm-gear clamps loosen and leak dust | Positive-bolted flanged face (100% dust-tight) |
| Fatigue Life | Flex cracks develop along clamp edges | Tested for >2,000,000 vibratory cycles |
| Chemical Resistance | Degrades under hot water and caustics | Full resistance to standard CIP/SIP washdowns |
| Installation Speed | Requires awkward clamp alignment | Direct bolt-through alignment with backing rings |
Technical Blueprint & Installation Engineering Notes
Engineering Drawing SOSHH-FLG-DN200-01: DN200 (ID 200mm / OD 280mm / PCD 240mm) 1.0mm profile with 8xM12 bolt pattern.
- Backing Flange Requirement: Because the integrated TPU flange is soft (1.0 mm to 2.0 mm), metal backing rings (304/316L SS flat or split rings) must be placed on the outer face to distribute bolt clamping torque evenly.
- Pre-Set Stroke Allowance: For vibrating hoppers, the sleeve is fabricated with an expansion margin (e.g., 125 mm to 130 mm free height for a 116 mm static gap) to accommodate horizontal and vertical stroke without pulling the flange roots.
- Fastener Torque: Tighten M12 bolts progressively in a criss-cross pattern to avoid localized pinch-cutting.
Global Regulatory Compliance & Regional Procurement
- North America: Fully compliant with FDA 21 CFR 177.2600, USDA Dairy sanitary standards, and NFPA 652/654 standards for combustible dust handling.
- European Union & UK: Fully certified under Framework Regulation (EC) 1935/2004, (EU) No 10/2011, and ATEX Directive 2014/34/EU.
- Asia-Pacific & Global Logistics: Rapid door-to-door delivery across major industrial hubs including Jakarta (Cengkareng), Surabaya, Bangkok, Singapore, and Ho Chi Minh City via DHL/FedEx Express under HS Code 3917.39.00.
Frequently Asked Questions
Q1: Can SOSHH® supply custom rectangular or square-to-round sleeves without tooling charges?
Yes. Our computer-controlled laser cutting and high-frequency welding processes allow us to produce custom transition sleeves directly from CAD/STEP files with zero mold fees, even for 1–2 unit prototype runs.
Q2: When should I choose the Anti-Static (ESD) TPU version over Ultra-Clear TPU?
Choose the anti-static version (10^8 to 10^10 Ohm) whenever transferring combustible powders (coffee, starch, flour, carbon black), operating in ATEX Zone 20/21/22 areas, or when severe triboelectric wall cling impairs visual monitoring. For standard gravity chutes in non-hazardous zones, the Ultra-Clear grade offers the highest visibility.
Q3: What thickness is recommended for vibratory dosing chutes?
For standard vibratory feeders and hoppers, 1.0 mm thickness provides the ideal balance between flexibility, low mechanical resistance, and tear strength. For abrasive granules or heavy negative pressure, 1.5 mm or 2.0 mm is available.
Request Engineering Support, CAD Step Files & Quotations
- Rapid Prototyping: Bespoke dimensional drawings confirmed within 2 hours; prototype samples shipped within 3–7 business days.
- Direct Manufacturer Pricing: Competitive sample and volume tier pricing for OEMs and plant end-users.
- Engineering Review: Submit your equipment flange dimensions (ID, OD, PCD, Hole Count, Clear Height) or upload your DWG/STEP models for instant DFM analysis.
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