ENGINEERING DATA

Technical Specifications

Complete engineering data for selecting and specifying a Coanda intake screen.

PRODUCT RANGE

Compare specifications across ADENCO-45, -70, -127, and the pre-assembled ADENCO-BOX

Parameter	ADENCO-45Compact	ADENCO-70Standard	ADENCO-127High capacity	ADENCO-BOXPre-assembled
Capacity per metre of width	35 l/s	67 l/s	150 l/s	Rated per unit, not per metre
Capacity per unit	5–35 l/s	25–100 l/s	37.5–225 l/s	5–100 l/s
Screen drop	450 mm	700 mm	1,270 mm	Inside the enclosed housing
Typical use	Drinking water, agriculture, irrigation, fish farms	Agriculture, drinking water, hydropower, retrofit, wastewater	Large hydropower, irrigation, wastewater, retrofit	Drinking water, agriculture, water treatment plants, wastewater

Common to every series

Slot: 0.5 to 2.0 mm (1.0 mm standard); narrower slots on request
Material: 304 stainless steel as standard; 304L, 316, 316L, duplex and super duplex on request
Lead time: 2–4 weeks typical
Higher flows: Units are placed side by side; an array of several ADENCO-127 units reaches 6,500 l/s

Need custom specifications? Contact our engineers →

DIMENSIONS

Screen and concrete structure dimensions

The four series drawn side by side to the same scale. Canal width is the clear opening your civil-works contractor forms in concrete beneath the screen, so it is usually needed before the screen is ordered. Capacities are stated for the 1 mm standard slot. Widths beyond the sizes below are built to order, and the screen drop and length do not change within a series however wide the unit is.

ADENCO-45

Compact

Drop: 450 mm
Length: 730 mm
Canal width: 450 mm
Per metre of width: 35 l/s

ADENCO-70

Standard

Drop: 700 mm
Length: 1,020 mm
Canal width: 650 mm
Per metre of width: 67 l/s

ADENCO-127

High capacity

Drop: 1,270 mm
Length: 1,500 mm
Canal width: 1,100 mm
Per metre of width: 150 l/s

ADENCO-BOX

Pre-assembled

Height: 900 mm
Length: 558 mm
Width: 1,000 mm
Per metre of width: 35 l/s

The arrows on each drawing show the three dimensions: drop is the vertical fall from the top of the screen to its lower edge, length is how far the screen extends horizontally, and width is the span across the flow. Within a series the drop and length do not change and capacity grows with width. ADENCO-45 passes 35 l/s per metre: a 300 mm unit delivers 10 l/s, a 600 mm unit 20 l/s. ADENCO-70 passes 67 l/s per metre: 750 mm gives 50 l/s, 1,250 mm gives 83 l/s. Widths shown are indicative; each screen is built to the width your flow requires. Higher flows are met by placing units side by side, usually at the standard 1 m width per unit. The ADENCO-BOX is built around either the ADENCO-45 (450 mm) or the ADENCO-70 (700 mm) screen; the dimensions shown are for the 450 mm version, and the housing itself is sized to each project.

Per metre of screen width

Series	Capacity (l/s per metre)	Screen drop (mm)	Length (mm)	Canal width (mm)
ADENCO-45	35	450	730	450
ADENCO-70	67	700	1,020	650
ADENCO-127	150	1,270	1,500	1,100

Standard sizes

Model	Capacity (l/s)	Screen width (mm)	Screen drop (mm)	Length (mm)	Canal width (mm)
ADENCO-45-0.15	5	150	450	730	450
ADENCO-45-0.30	10	300	450	730	450
ADENCO-45-0.45	15	450	450	730	450
ADENCO-45-0.60	20	600	450	730	450
ADENCO-45-0.90	30	900	450	730	450
ADENCO-45-1	35	1,000	450	730	450
ADENCO-70-0.50	33	500	700	1,020	650
ADENCO-70-0.75	50	750	700	1,020	650
ADENCO-70-1	67	1,000	700	1,020	650
ADENCO-70-1.25	83	1,250	700	1,020	650
ADENCO-70-1.5	100	1,500	700	1,020	650
ADENCO-127-0.5	75	500	1,270	1,500	1,100
ADENCO-127-1	150	1,000	1,270	1,500	1,100
ADENCO-127-1.25	188	1,250	1,270	1,500	1,100

ADENCO-BOX standard sizes

Model	Capacity (l/s)	Screen width (mm)	Screen drop (mm)
ADENCO-BOX-45-0.30	10	300	450
ADENCO-BOX-45-0.60	20	600	450
ADENCO-BOX-45-1	35	1,000	450
ADENCO-BOX-70-0.5	33	500	700
ADENCO-BOX-70-0.75	50	750	700
ADENCO-BOX-70-1	67	1,000	700
ADENCO-BOX-70-1.25	83	1,250	700
ADENCO-BOX-70-1.5	100	1,500	700

Need a width, drop or slot outside these sizes? ADENCO builds to order from 5 l/s upward, and units are placed side by side for higher flows. The BOX housing is sized to each project around its 450 mm or 700 mm screen.

DESIGN PARAMETERS

Key Design Variables

Every Coanda screen is designed for its site. These are the variables that set how much water it passes and how well it cleans itself, in the order a designer decides them: the structure first, then the screen surface, then the conditions it operates under.

Macro view of V-shaped wedge wire on a Coanda screen face, showing the tilted wedge wires and the slot opening between them

Screen geometry

Acceleration plate dropVertical drop from the weir crest to the top of the screen. It sets the water velocity at the top of the screen; about 1 m/s at a 1 mm slot keeps the screen face self-cleaning.

Screen slope10° to 60°. Capacity changes almost linearly with angle. Steep screens shear flow through the wedge wires; screens at a shallow angle pass more water but depend more on slot width and bypass flow.

CurvatureA concave panel raises capacity 8 to 16% over a straight (uncurved) screen of the same length and makes the flow through the lower part of the screen more even.

Screen lengthThe distance the water travels down the screen face. A longer screen passes more water, and the gain is more than proportional: a screen twice as long passes about 2.4 times the flow, so each added metre yields more than the one before.

Screen surface

Slot widthThe slot is the clear opening between neighbouring wedge wires: water passes through it, and anything larger is carried off the screen. 0.5 to 2.0 mm (1.0 mm standard); narrower slots on request. Choose the slot width by the smallest debris that must be kept out, not by capacity: on a steep screen a 0.5 mm slot passes nearly as much water as a 1.0 mm slot.

Wire widthTogether with the slot it determines the open area of the screen. Selected for durability under the expected debris load.

Wire tilt angle5° standard, 3° to 7° available, held to ±0.25° in manufacture. More tilt passes more flow; beyond 7° the jet separates from the wedge wires and the Coanda effect is lost.

Operating conditions

Bypass flowWater carried over the lower edge of the screen deepens the flow on the screen face and raises capacity, most of all on screens at a shallow angle. Every capacity figure states the bypass fraction it assumes.

Tailwater and backpressureCapacity figures assume a free-draining chamber under the screen and tailwater below its lower edge. If either water level rises up to the screen, capacity falls.

Grouping and sensitivities follow the US Bureau of Reclamation (USBR) Coanda Design Guide (Wahl, 2003, report R-2003-03). ADENCO confirms the controlling design values for each site in the hydraulic calculation issued with the quotation.

MATERIALS

304 : General purpose, standard corrosion resistance

304L : Low carbon variant for improved weldability

316 : Superior corrosion resistance, marine environments

316L : Low carbon, optimal for corrosive water chemistry

Duplex 2205 : Austenitic-ferritic, for high-chloride and high-strength applications

Super Duplex 2507 : Premium duplex for seawater and desalination intakes

All welds are pickled and passivated to restore the chromium oxide layer and remove heat-affected-zone corrosion.

DOWNLOADS

Datasheets, general arrangement (GA) drawings and CAD files are issued with every quotation, with technical drawings prepared in 2 business days. Request the document package for your project by sending a request for quotation (RFQ).

The wedge wire surface of a Coanda intake screen, curving down from the acceleration plate