The Apollo Under Drain System features a sophisticated header-lateral design, combining precision-engineered welded wedge wire screens with internal uPVC distributor pipes. This innovative design ensures uniform filtration during operation and uniform backwash for enhanced cleaning efficiency. By eliminating the need for a gravel support layer, the Apollo Under Drain System optimizes filter bed performance, offering long-lasting, reliable service with reduced maintenance requirements.
The all-welded wedge wire screens, with their small apertures and smooth surface, allow for direct retention of filter media, effectively preventing common issues like media loss, bed upsets, and non-uniform backwashing. The result is a more efficient filtration process, minimizing downtime and operational costs.
The Apollo Under Drain System operates based on a header-lateral configuration, where the welded wedge wire screens are integrated with internal uPVC distributor pipes.
Filtration Phase: During filtration, the wedge wire screens with their small apertures (as fine as 0.15 mm) retain the filter media directly, allowing for efficient filtration and preventing the loss of sand or other media.
Backwashing Phase: The system is designed to deliver uniform backwash through the internal distributor pipes. This ensures thorough cleaning of the filter bed, preventing the formation of mud balls and ensuring consistent performance.
The absence of a gravel support layer reduces the head loss within the filter, enabling the filter bed to operate at a higher flow rate and increased capacity.
| Parameter | Specification |
|---|---|
| System Type | V-Wire (Wedge Wire) Under Drain System — Nozzle-less design |
| Application | Rapid Gravity Filters (RGF) / Dual Media / Multi-Media Filters |
| Construction | Stainless Steel (SS304 / SS316 / SS316L) and/or uPVC housing |
| Wire Profile | V-shaped / Wedge Wire for non-clogging performance |
| Slot Opening / Aperture | 0.15 mm standard (0.10 – 0.30 mm optional) |
| Support Rods | Triangular / Semi-elliptical rods welded to wedge wires |
| Open Area | 15–22% depending on configuration |
| Drain Lateral Configuration | Single-block, modular laterals (bottom-mounted) |
| System Layout | Header–Lateral arrangement with uniformly spaced arms |
| Maximum Operating Pressure | Up to 6 kg/cm² |
| Design Air Scour Rate | 55–75 m³/hr/m² |
| Design Backwash Water Rate | 25–40 m³/hr/m² |
| Backwash Distribution Pattern | Uniform Air + Water backwash across media bed |
| Gravel Layer Requirement | Not required — media directly retained by V-wire |
| Media Retention Mechanism | Aperture-driven retention — prevents media leakage |
| Anti-Clogging Feature | Self-cleaning due to V-wire geometry and tapered slot |
| System Headloss | < 50 mm under normal operating conditions |
| Filter Cycle Duration | Extended due to enhanced backwash efficiency |
| Corrosion Resistance | Resistant to chlorine, ozone, alum, ferric salts |
| Estimated Life | 15–25 years depending on metallurgy & operating conditions |
| Compliance | AWWA / NSF/ANSI where applicable |
