TWIN SEAL FLAP ISOLATOR
| DESCRIPTION | MATERIAL USED |
|---|---|
| SIZE RANGE | Upto 2000 mm X 2000 mm* |
| DESIGN PRESSURE | 2000 mmWC* |
| TEMPERATURE RANGE | Upto 350 °C |
| DESIGN GOVERNING STANDARD & TESTING | Manufacturer's standard |
| MODE OF OPERATION | Manual / Electric / Pneumatic / Hydraulic |
* Higher Sizes / Pressure available on request
Twin Seal Flap Isolator (For Pulverised Fuel Mill Isolation)
Safety and reliability have been major challenges in coal-fired boilers at thermal power stations. Fouress, in technical consultation with discerning customers, developed an effective solution for reliable isolation of PF Mills through the ingenious concept of the Twin Seal Flap (TSF) Isolator. This design guarantees 100% sealing efficiency, ensuring safe access for on-load maintenance of PF Mills.
Most power plants in India have traditionally used pneumatically operated Guillotine Isolators for mill isolation. Since the temperature of the primary air at this location exceeds 300°C and these dampers operate only during isolation, sharp temperature variations over time tend to warp the blades of conventional Guillotine Dampers.
Twin Seal Flap Isolators have proven their efficiency since their first installation at Koradi Thermal Power Station in 1982, followed by more than 500 successful installations across thermal power stations in India.
Twin Seal Flap Isolator – Features
- Perfect solution for isolation of Pulverised Fuel Mill (Coal Mill) enabling safe on-load maintenance.
- Unique double row of seals ensures 99.99% sealing efficiency on flow.
- Minor leakage through the first row of seals is vented to atmosphere through a vent valve, ensuring virtually 100% leak tightness across the duct.
- Capable of handling pressures up to 2000 mm WC.
- Designed for temperature range up to 350°C.
- Equipped with self-lubricated and self-aligning outboard mounted special gunmetal bearings.
- Swinging flap design prevents jamming of the blade even under heavy dust accumulation.
- Flap remains inside the duct at all times, eliminating blade warping due to temperature variations.
- Reduced structural load on the duct as no superstructure is required above the duct.
- Duct-level mounted operators and outboard bearings facilitate easy maintenance.
- Full bore design ensures minimum pressure drop.
Twin Seal Flap Isolator – Design Specifications
| PARAMETER | DESCRIPTION | DETAILS |
|---|---|---|
| SIZE RANGE | Upto 2000 mm x 2000 mm* | |
| PRESSURE RATING | Upto 2000 mm WC* | |
| TEMPERATURE RANGE | 350°C | |
| MATERIAL OF CONSTRUCTION | FRAME | Carbon Steel |
| BLADE / FLAP | Carbon Steel | |
| SHAFT | ASTM A479 Type 431 / EN57T | |
| SEAL TYPE | SS 316 | |
| BEARING | Fouress Gunmetal Bush Bearings | |
| DESIGN GOVERNING STANDARD & TESTING | Fouress Standard | |
| SEAL TYPE | Twin | |
| MODE OF OPERATION | Manual / Electrical / Pneumatic / Hydraulic | |
| NO OF DRIVES | Single / Dual | |
| INSTALLATION ARRANGEMENT | With Top Hat Arrangement in the Duct |