Overview
The Storz quick-release coupling is the foundation of the entire pneumatic discharge line on Feldbinder silo trailers. On the horizontal, non-tipping EUT range, Storz couplings connect the compressor hose from the blower to the discharge spigot and link the conveying hoses between the outlet cones and the delivery point. On the tipping-tank KIP range (Kippsilo) — where the tank is raised hydraulically and discharge is pressure-assisted — coupling integrity and seal quality are even more critical, because the entire product path operates under positive pressure.
From a Feldbinder service perspective, three things matter most: matching the coupling material to the medium being conveyed (aluminium for PE/PP granules and dry bulk materials; stainless steel for food-grade EUT 316L versions), choosing the right seal (black or white NBR for general use, silicone and Viton wherever hygiene or chemical resistance is required), and ensuring dimensional compatibility with the existing fittings on the specific trailer. PHS Magnum holds the complete Storz range — from standard stock items through to direct-delivery specials.
Specifications and Materials
Couplings (male/female threaded and swivel)
| Version | Alloy / standard | Seal |
|---|---|---|
| Polish aluminium (standard stock) | AK 11 (AlSi 11) to PN-91/M-51031 | Black NBR |
| German aluminium | 14307, 14308, 14309 | White NBR |
| Brass | 14307, 14308, 1430, 86205 | White NBR |
| Stainless steel | 14307, 14308, 14309 | Green Viton |
| Swivel couplings | All sizes | As per material |
Standard stock covers male and female threads in 2", 2½", 3" and 4" (Polish-cast aluminium).
Storz Suction Connectors
| Fixing method | Material | Standard | Seal |
|---|---|---|---|
| GBS clamps | German aluminium | 14301, 14322, 14323 | White NBR |
| GBS clamps | German aluminium, steel hose spigot | — | White NBR |
| GBS clamps | Stainless steel, size B(75) | 14307 | Green Viton |
| Clam-shell collars | All sizes | DIN 2817 | White NBR |
Blanking Caps and Reducers
| Component | Material | Standards | Seal |
|---|---|---|---|
| Blanking cap | Polish aluminium AK 11 (AlSi 11) to PN-91/M-51031 | — | Black NBR |
| Blanking cap | German aluminium | 14310, 14311, 14312, 14313 | White NBR |
| Reducer | Polish aluminium AK 11 | — | Black NBR |
| Reducer | German aluminium | 14341, 14342, 14343 | White NBR or silicone |
| Reducer | German aluminium with steel insert | 1434 | White NBR |
Storz System Seals
| Sizes | Materials |
|---|---|
| C(52), B(75), A(110), 90, 100, D, 125, 150, 165, 205 | White NBR rubber; silicone (high-temperature); Viton (green) |
| Seals for threaded couplings | White NBR rubber; PTFE (reinforced) |
Sizes and Types
- Threaded couplings (standard stock, Polish aluminium): 2", 2½", 3", 4" — male and female.
- Suction connectors: GBS-clamp and clam-shell collar types; stainless available in size B(75).
- Seals: full range from C(52) and B(75) through A(110) to large sizes 90, 100, D, 125, 150, 165 and 205.
- Blanking caps and reducers: in sizes corresponding to 2"–4" couplings.
Compatibility with Feldbinder Silo Trailers (EUT/KIP)
Storz couplings are selected to match the actual discharge-line configuration of the specific Feldbinder trailer:
- EUT (horizontal, non-tipping) — discharge spigots (Auslaufstutzen) and the compressor hose are joined with Storz couplings. On food-grade stainless-steel 316L versions we fit stainless couplings with Viton seals, or aluminium couplings with white NBR, to maintain hygiene compliance throughout the product path.
- KIP (Kippsilo, tipping) — with hydraulic tank elevation and pressure-assisted discharge, coupling integrity and correct seal selection for the operating pressure of the line are essential.
Thread type (male/female) and coupling size must match the existing fittings on the trailer. When ordering, please confirm the current size and seal type fitted. Full category catalogue: spare parts.
Common Faults on Feldbinder Silo Trailers
Field experience with Feldbinder silo-trailer service throws up these recurring Storz-related issues:
- Worn or hardened coupling seal — causes leaks and pressure loss during discharge. On EUT 316L food-grade trailers we replace with FDA-grade silicone or Viton rather than standard NBR, where the product category allows it.
- Worn coupling lugs (crowns) — make it impossible to engage and lock the coupling reliably; the crown or locking ring needs replacing.
- Corrosion of threads on aluminium couplings — where aggressive granules are carried, switching to stainless-steel or brass couplings is advisable.
- Damaged suction connector spigot — on GBS-clamp assemblies the spigot can be reamed out by repeated clamping; replacement of the connector or spigot only (German aluminium or steel) is straightforward.
- Missing or broken blanking-cap chain — a minor item, but lost caps are a real recurring cost; we stock chains in steel and stainless steel.
We do not quote service-life figures that cannot be verified — replacement intervals depend on the medium, line pressure and operating intensity. Diagnostics and replacement are carried out as part of our silo-trailer service.
Availability and Delivery
The PHS Magnum parts store in Chorula, near Opole holds standard Storz stock — Polish-aluminium AK 11 couplings (2"–4"), blanking caps, reducers and the full seal range in NBR/silicone/Viton — available for immediate dispatch. Direct-delivery items (German aluminium, brass, stainless steel, swivel couplings) are sourced on short lead times. Delivery by courier throughout Poland and to the DACH region.
Related Categories
- Pneumatic Hoses — fitted to Storz suction connectors
- Hose Clamps — GBS worm-drive clamps and clam-shell collars
- Rubber Mallets and Storz Spanners — Coupling tools and tank-tapping mallet for daily discharge operations.
- Non-return Valves — in pneumatic discharge lines
- Full Spare Parts Catalogue
- PHS Magnum Silo Trailer Service · Aleksy Pasternak — pasternak.me
See also: This category in the full PHS Magnum network catalogue (all makes) →
Author: Aleksy Pasternak — Managing Partner PHS Magnum, 20 years in the industry, ISO 9001:2015 internal auditor (DEKRA).
