TPU Flexible Connectors: Leak-Proof Design, Abrasion & Temperature Specs
High-Performance TPU Flexible Connectors for Leak-Free Powder Handling
Powder lines using hose-clamp connections fail most often at the clamp edge, where uneven tightening concentrates stress and tears the sleeve. SOSHH high-performance flexible connectors are made from polyether TPU, selected for abrasion resistance, flex-fatigue endurance and hydrolysis stability. This guide specifies the material properties governing leak resistance and service life so you can size the correct sleeve for your process.
What Causes Leaks and Downtime in Powder Lines?
Most sleeve failures in powder handling are not material failures — they are installation and edge-stress failures:
- Uneven clamp torque creates local pressure peaks that tear the sleeve at the clamp edge.
- Low-elongation materials (silicone, rubber) crack under high-frequency vibration instead of absorbing it.
- Moisture and CIP heat degrade standard polyester TPU, causing premature embrittlement.
SOSHH removes these failure modes with polyether TPU and a tool-free snap-in design that eliminates the clamp edge entirely.
Material Specifications That Matter
- Abrasion resistance: 39.0 mg (DIN). Resists wear from cement, glass cullet, and abrasive powders.
- Tensile strength: 40 MPa. High tear resistance under load.
- Elongation at break: 600%. Absorbs vibration instead of tearing.
- Continuous temperature: -20 °C to +110 °C. Maintains cold-weather flexibility and withstands CIP heat.
- Peak temperature: +120 °C (short surge). Withstands transient hot-air exposure without collapse.
- Surface resistivity (Standard): >10¹² Ω. Insulating grade for general powder transfer.
- Surface resistivity (Anti-static): <10⁹ Ω (AS option). Essential for ATEX dust-zone electrostatic dissipation.
- Wall thickness: 1.5 mm. Creates a crevice-free monolithic bore.
Polyether vs. Polyester TPU — Why It Matters for Food & Pharma
- Polyether TPU is hydrolysis-resistant and anti-microbial — essential for CIP/SIP washdown cycles.
- Polyester TPU is cheaper but hydrolyzes — it chemically breaks down under hot water and steam, yellowing, stiffening and cracking over time.
- For food, dairy and pharma lines running CIP, polyether is the correct specification.
When TPU Is — and Is Not — the Right MaterialUse polyether TPU when:
- Powder is abrasive (cement, glass, minerals)
- The line vibrates (sifters, screeners)
- CIP/SIP cleaning is required
- Continuous temperature stays within -20 °C to +110 °C
Choose CNC-machined pure PTFE instead when:
- Temperature exceeds +150 °C
- Strong acids/alkalis or solvents are present
- A fully metal-free, chemically inert path is required (PTFE: -70 °C to +260 °C continuous)
Compliance and Documentation
- FDA 21 CFR 177.2600 (Report Ref: TQT4821B36E)
- Formulated in accordance with EC 1935/2004 & EU 10/2011
- Material Test Certificate (MTC) shipped with each order
- CAD/STEP files available for OEM design integration (NDA required)
FAQQ: Polyether or polyester TPU for food/pharma?
A: Polyether — it is hydrolysis-resistant and anti-microbial, essential for CIP; polyester degrades in moisture and heat.
Q: What is the surface resistivity for ATEX dust zones?
A: Standard grade is >10¹² Ω (insulating). For dust-explosion zones, specify the AS anti-static option (<10⁹ Ω) to prevent electrostatic charge accumulation.
Q: Can you make non-standard flanges?
A: Yes — laser-cut and welded. Send dimensions or a 3D model for a 24-hour approval drawing.
Q: What is the ROI of switching from rubber to TPU?
A: TPU has a higher upfront cost but delivers a longer service life with no black-soot contamination and fewer changeovers — especially on abrasive or CIP-washed lines.
