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Headworks Calculator — Bar Screens & Grit Chamber
Screen-channel width with velocity checks · Kirschmer head loss · horizontal grit chamber with 0.2 mm sand capture
iWhat this tool does
Two headworks units that protect everything downstream. The screen is sized by what happens through the bars;
the grit chamber by keeping the horizontal velocity constant so sand falls out but organics don't. Both are checked at peak flow.
1Bar screens
Screenings assumptions
2Horizontal grit chamber
Results — bar screensPEAK FLOW
Channel width
—m
Head loss — clean
—cm
Head loss — 50 % clogged
—cm
| Item | Value | Unit |
|---|
Results — grit chamberPEAK FLOW
Length
—m
Width × depth
—m
Sand capture
—OK
| Item | Value | Unit |
|---|
Headworks instrumentationMAPPED TO OUR RANGE
Rakes / grit conveyors are mechanical equipment, not our line — the instruments we carry and quote at factory-direct price are below.
| Duty | Instrument | Model / spec | Qty |
|---|
Quote this headworks' instruments at factory price
Open-channel flow, level control for rake actuation, and pump-station instruments at the manufacturer's ex-works price — our margin comes solely from the export tax rebate.
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Sources & parameter basis
| [1] | Bar-screen design factors (Clay et al.) & rectangular grit-chamber worked design — velocities (through-bar 0.6–1.0 mech / 0.3–0.6 manual; V_h 0.3 m/s), v_s 0.016–0.022 m/s for 0.2 mm sand, detention 45–90 s. |
| [2] | Ten States Standards / US headworks practice — approach velocity 0.3–0.9 m/s, redundant channels. |
| [3] | Metcalf & Eddy, Wastewater Engineering, 5th ed. — screenings 0.0035–0.0375 m³/10³ m³, Kirschmer shape factors, bar spacings, head-loss allowances. |
Velocity control is the design. A grit chamber only removes grit if V_h stays ≈ constant as flow varies — specify a proportional weir or flume.
Rake actuation for mechanical screens is set on measured head loss, so keep the differential level transmitter in the budget.
Questions about a duty, a specification, or transparent sourcing? Contact our application engineers →
Cite this tool / 引用此工具
If you use this result in a report, specification or client document, please cite it as below. It takes one line and lets engineers find us. 如果您把计算结果用于报告、规格书或客户文件，请按下列方式引用。
Jiuyuhub. "Headworks Calculator — Bar Screens & Grit Chamber". Jiuyuhub, https://jiuyuhub.com/headworks-design.html
Licensed for internal and commercial technical use (CC BY 4.0). 内容可用于内部及商业技术用途。 Questions? Ask our engineers