PRODUCTS
Triden Screens STF Front Discharge
- For lower flows and confined areas
- All stainless steel axles, drive, links, and supports
- No submerged drive parts
- Stainless steel links are significantly stronger than plastic hooks or perforated panels
- Continuously cleaned with no rotating brushes
- Easy access to lubrication points- only two grease fittings
- Easy installation and maintenance
- Low operating costs
- 304 SS construction standard
- Practical design and material selection provide reliable and efficient operation
- Fully enclosed for operator safety
- Low profile bottom shoe and brush limit headloss and screen bypass
- Low friction UHWMPE surfaces greatly reduce wear
- Compact/Low profile design
Sizing and Technical Information
Flow vs. Channel Width vs. Headloss for 6 mm Triden Screen
Graph assumes: V1 = 2 fps and D = 2 (C)
Graph assumes: V1 = 2 fps and D = 2 (C)
Channel Schematic
| Screen Opening Sizes | 3mm | 6mm | 9mm | 12mm |
| Open Area % with clean screen | 62.2 | 69.8 | 72.4 | 75.7 |
| Open Area % with 30% blocked | 43.6 | 48.8 | 50.7 | 53.0 |
Recommendations for Designing a Channel
- Maintain V1 above 2 fps to ensure scouring
- Keep V1 acceptable during off-peak flows by setting D = 2 (C)
- Channel Depth = D + 12" freeboard
- Narrower grid openings will reduce efficiency
Conversion Factors
- Headloss in inches = (V22-V12)(0.186) where V1 and V2 are in ft/s
- Flow 1 mgd = 694.44 gal/min = 1.5472 ft3/s
- Length 1 ft = 0.3048 meters
- 1 in = 2.54 centimeters
- Volume 1 ft3 = 7.4805 gallons = 28.317 liters
Example Calculation for Existing Channel
- Given: C = 3' D = 6' V1 = 2 fps
- G = C - 6" = 30"
- Q = C (D) V1 = 36 ft3/s = 23.27 mgd
- To determine headloss for a 6 mm grid with clean screen
- find: Open Area = G (D1) eff = 9.60 ft2
- V2 = Q / Open Area = 3.75 fps
- h = (V22-V12) 0.186
- h= 1.87 in
Nomenclature
- C = channel width
- D = depth of flow
- D1 = D - 6"
- G = grid width = D - 5"
- Q = flow
- h = headloss
- V1 = Inlet Velocity
- V2= Exit Velocity
- eff = grid efficiency
Channel Schematic
Grid eff = Grid Open Area / Grid Total Area
Screen eff = Grid Open Area / Flow Area
Grid Open Area = Grid Total Area - Grid Closed Area (due to the static and dynamic grid elements)
Flow Area = (C) (D)
Grid Width (G) = Channel Width (C) - 5"
Screen eff = Grid Open Area / Flow Area
Grid Open Area = Grid Total Area - Grid Closed Area (due to the static and dynamic grid elements)
Flow Area = (C) (D)
Grid Width (G) = Channel Width (C) - 5"
6" Hyd. Jump