From testing to real-world applications: polyTUBE® performances confirmed even under challenging operating conditions. Two field installations — ISOTEX Srl and VETROBALSAMO SpA — document how the Ø1000 mm vent filter behaves outside the standard concrete batching envelope.
ISOTEX Srl — microfine hydrated lime
End user manufacturing formwork systems for the construction industry – Sector 1100.
Initial context. At the Poviglio production plant in Reggio Emilia, five old bag filters were installed and were serving three cement powder silos and two hydrated lime silos, all pneumatically loaded from road tankers. They have subsequently been replaced with SILOTOP® polyTUBE® units. On the cement silos, the performance of SILOTOP® polyTUBE® proved to be optimal. On the hydrated lime silos, however, the same filters did not deliver satisfactory performance, resulting in frequent VCP valve openings and dust emissions.
The installation represented a real-world and challenging application, characterized by microfine hydrated lime dust, loading operations carried out using a tipping tanker (an average of one load per week), and high airflow peaks with the resulting high-pressure levels.
Solution adopted. Replacement of the two SILOTOP® polyTUBE® units serving the hydrated lime silos with two WAMFLO® Vent polyTUBE® Ø1000 mm units.
Objective. To validate and further develop polyTUBE® solutions through comparative testing of different filtration configurations, performance optimization (ΔP, airflow rate, cleaning efficiency), verification of reliability over the medium term, and expansion of the application range beyond standard SILOTOP® configurations.
Testing and monitoring
The activity has been carried out over a period of more than 12 months (from February 2025 to the present day) and has included monitoring of loading operations and airflow rates up to approximately 4,100 m³/h, ΔP measurements showing low and stable values, and verification of system behaviour during silo filling up to 95% capacity, air-only cycles, and sudden pressure peaks.
Key results
- Filtration performance — Loading operations rated as “excellent” by the customer ISOTEX Srl; very low and stable ΔP values; no alarms detected on the filters under test.
- Filter element cleaning — Inspected polyTUBE® elements remained clean, even after critical events (such as a power outage).
- Improved customer process — More efficient silo filling; reduced loading frequency, and therefore better utilization of silo capacity.
- Customer satisfaction — Direct positive feedback: the customer was “satisfied” with the overall performance of the system.
The polyTUBE® solution delivered greater application flexibility, operational robustness even under non-ideal conditions, ease of maintenance and servicing, and a solid foundation for expansion into more demanding industries.
The Isotex case demonstrates that WAMFLO® polyTUBE® is not simply an upgrade, but an evolutionary platform: tested in real-world applications, validated over time, and capable of adapting to different industrial environments. From cement to hydrated lime, and all the way to the most demanding applications, polyTUBE® continues to prove its reliability, performance, and potential for further evolution in the field.
VETROBALSAMO SpA — sand storage silo
End user glass industry – Sector 4000.
Context. The customer operates several bag filters serving various powder silos that are pneumatically loaded using tipping road tankers. In another area of the plant, the customer has been successfully using WAMAIR® Spot polyTUBE® filters on conveyor belts. As a result, the customer decided to replace the bag filter serving the sand storage silo with a WAMFLO® Vent polyTUBE® Ø1000 mm.
The objectives were to test polyTUBE® technology in a different application environment, and to reduce the maintenance and compressed air issues experienced with the other bag filters.
Installation date: 22 November 2024.
Feedback. As of today, the WAMFLO® Vent polyTUBE® Ø1000 mm is operating correctly and remains fully in service. The silo is loaded using a tipping road tanker on a weekly basis.
Emphasis should be placed on the height difference between the installed bag filters and the WAMFLO® Vent polyTUBE® Ø1000 mm, which translates into easier maintenance access and improved serviceability for plant operators.
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