Introduction
On a Spitzer SF or SK silo trailer, the filling hatch is the top loading manhole — the opening in the upper section of the tank through which PE/PP granules or other bulk dry material is loaded. After every loading cycle, this hatch must be closed airtight, and it is the gasket seated between the hatch cover and the manhole rim that maintains that seal. The gasket forms the boundary between the tank interior and the outside world: it prevents cargo loss, keeps moisture and contamination out, and maintains the working pressure during pneumatic-aeration discharge.
Filling hatch gaskets operate in demanding conditions. They are compressed and released with every opening and closing cycle, continuously exposed to weather, dust and direct contact with the cargo. Over time the gasket material hardens, cracks or loses its resilience, causing the hatch to no longer close uniformly. PHS Magnum holds a filling hatch gasket stock in Chorula near Opole covering the most widely used silo trailer brands, so the right gasket can be identified and dispatched without waiting on overseas supply.
Specification and Materials
We supply filling hatch gaskets matched to specific silo trailer brands. The range covers gaskets for Spitzer, Feldbinder, Omeps (new and old type), Kässbohrer, LAG and other manufacturers.
| Component | Application | Selection basis |
|---|---|---|
| Filling hatch gasket | Top loading manhole of a silo trailer | By brand and hatch type |
Correct fitment depends not on a single dimension but on compatibility with the specific hatch of a given manufacturer. The same position across different brands — and even across generations of the same brand, as with Omeps where new and old types differ — can have a different profile and cross-section. For this reason, our range is organised by brand and hatch type rather than by universal sizing.
The precise material and dimensions of each gasket are matched to the brand and hatch type of the trailer. The seating geometry and seal profile are specific to each design and do not reduce to a single universal measurement.
Sizes and Types
Our filling hatch gasket range is organised by silo trailer brand and hatch type. Specific DN dimensions are not the reference for this category; selection is carried out by brand and type rather than nominal bore.
| Brand | Hatch type | Notes |
|---|---|---|
| Spitzer | Filling hatch | SF/SK series |
| Feldbinder | Filling hatch | — |
| Omeps | New type / old type | Two variants |
| Kässbohrer | Filling hatch | — |
| LAG | Filling hatch | — |
| Other brands | Filling hatch | On request |
The common thread across the range is coverage of the most widely used silo trailer brands in the DACH market and Poland. For Omeps, the range is split into new and old hatch types — these are two different gasket variants, so it is worth specifying which type applies when ordering. For other brands, selection is based on stating the manufacturer and, where necessary, the hatch type or production year.
Compatibility with Spitzer Silo Trailers (SF/SK)
The filling hatch gaskets in our range are matched directly to Spitzer, Feldbinder, Omeps, Kässbohrer and LAG — these are not generic substitutes of uncertain origin, but components that correspond to the actual hatches produced by those manufacturers. On Spitzer SF and SK series silo trailers, the top loading manhole is sealed with a gasket selected specifically for the Spitzer filling hatch.
Because PHS Magnum services both Spitzer trailers and related Feldbinder designs as well as the other brands listed, we select gaskets with reference to the actual hatch in question — not the manufacturer name alone. When ordering, it is essential to state the trailer brand and, where possible, the hatch type (as with Omeps: new or old), since these details determine the correct fit.
Common Faults
In everyday service practice, the filling hatch gasket is a wear item replaced on a periodic basis — it is active at every loading cycle and continuously exposed to the elements. Typical signs that replacement is due include:
- Hardening and loss of resilience — the gasket no longer returns to shape after compression, causing the hatch to close unevenly.
- Cracks and cuts — these break the continuity of the seal and lead to leaks at the top manhole.
- Permanent deformation — a compressed, flattened cross-section no longer provides adequate contact pressure.
- Contamination and bonding with cargo residues — this impedes closure and accelerates wear.
In each of these cases the remedy is to replace the gasket with a component matched to the brand and hatch type. At the same time, it is worth inspecting the butterfly bolts that secure the filling hatch — the gasket and bolts work together to maintain hatch integrity.
Availability and Delivery
Filling hatch gaskets for the most widely used silo trailer brands — Spitzer, Feldbinder, Omeps (new and old type), Kässbohrer, LAG and others — are held in stock at our warehouse in Chorula near Opole. Dispatch is by courier throughout Poland and to DACH countries (Germany, Austria, Switzerland).
To identify the correct gasket, please provide the silo trailer brand and the filling hatch type. For details and an individual quotation, request a quote.
Related Categories
- Top Hatch Bolts — complete wing-nut bolt assemblies (M20x100–M20x140, galvanised steel) for securing the top filling hatch, used in conjunction with the hatch gasket.
- Rear Hatch Gaskets — gaskets for rear access hatches and manholes on Spitzer, Feldbinder and Kässbohrer silo trailers.
- Flange Gaskets — interflange and flange gaskets for Spitzer, Feldbinder, AKO and Prokosch systems.
- Spitzer SF and SK Parts — overview of wear and structural parts for the SF and SK series.
- All Spare Parts — complete parts catalogue for silo trailers in the PHS Magnum stock.
- Silo Trailer Service — PHS Magnum — refurbishment, accident repair and specialist silo trailer servicing.
- pasternak.me — expert resource on silo trailer service, transloading and bulk material transport.
See also: This category in the full PHS Magnum network catalogue (all brands) →
Author: Aleksy Pasternak — Managing Partner PHS Magnum, 20 years in the industry, ISO 9001:2015 internal auditor (DEKRA).
