Engineering & Procurement Guide: Internal Clamp Flexible Connector Size Chart & Tool-Free Installation
1. Core Sizing Parameters: Stainless Steel Spigot Size Chart
Achieving a perfect seal starts with correct sizing. The golden rule for snap-in connectors is: Always size the weld-on steel spigot based on the exact Outer Diameter (OD) of your site's equipment or piping. We offer the standard SF-series steel joints in two heights: 50mm (Standard) and 90mm (Extended) to accommodate different welding clearance requirements.
Standard 50mm Height Spigot (Standard Profile)
Ideal for standard vibrating sifters, discharge chutes, and compact spaces.
| Nom. Size | Pipe/Equipment OD (D) | Spigot Inner Dia (d) | Spigot Height (h) |
| DN150 | 154 mm | 150 mm | 50 mm |
| DN200 | 204 mm | 200 mm | 50 mm |
| DN250 | 254 mm | 250 mm | 50 mm |
| DN300 | 304 mm | 300 mm | 50 mm |
| DN400 | 404 mm | 400 mm | 50 mm |
(Note: Standard sizes cover DN76 up to DN800. Custom CNC machining is available for non-standard pipe outer diameters.)
2. The 4-Step Tool-Free Installation Guide
The primary ROI of the internal clamp flexible connector lies in its unparalleled assembly speed. Once the steel spigots are welded, operators can assemble or disassemble the sleeve in under 30 seconds without any tools.
- Measure & Match: Use calipers to verify the exact outer diameter of the process pipe. Ensure it matches the procured stainless steel spigot.
- Align & Weld: Position the straight, un-grooved end of the spigot flush against the process pipe. Tack weld for alignment, then complete a full continuous weld. Crucial: Grind the weld seam perfectly smooth to prevent powder entrapment.
- Align the Flexible Sleeve: Once the welds have cooled, position the transparent TPU flexible sleeve between the upper and lower welded spigots.
- Snap & Seal: Pinch the built-in rigid ring gasket of the TPU sleeve, push it into the internal groove of the steel spigot, and release. The ring will snap open, locking itself firmly into place for a 100% crevice-free, airtight seal.
3. Why Procurement & Engineers Prefer Snap-In TPU Connectors
For professionals in the pharmaceutical, food processing, and fine chemical sectors, traditional hose clamps create uneven pressure and unsanitary dead spots. The internal clamp system solves these critical pain points:
- Zero Crevices, Zero Leaks: The internal snap-in design allows product to flow seamlessly over the transition, eliminating dead zones and preventing cross-contamination.
- FDA-Compliant Durability: Made from highly transparent, abrasion-resistant, and tear-proof TPU (Thermoplastic Polyurethane), meeting strict food-grade sanitary standards.
- No Falling Hardware: The integrated gasket design entirely eliminates the risk of hose clamps, nuts, or bolts vibrating loose and falling into the product stream.
- Maximized OEE (Reduced Downtime): Sifter screen changes and routine pipe cleaning take seconds instead of minutes, drastically reducing costly maintenance downtime.
Need 3D CAD drawings or a bulk procurement quote for your next facility upgrade? Visit for in-stock and custom internal clamp flexible connectors ranging from DN76 to DN800.
