2. SLUICE GATE
A sluice is a water channel that is controlled at its head by
a gate (from the dutch word “sluis” ). For example,
millrace is a sluice that channels water towards a water
mill. The terms “sluice gate” , "knife gate", and "slide
gate" are used interchangeably in thewater/wastewater
control industry.
A sluice gate is traditionally a wooden or metal plate that
slides in grooves in the sides of the channel. Sluice gates
are commonly used to control water levels and flow rates
in rivers and canals.They are also used in wastewater
treatment plants and to recover minerals in mining
operations, and in watermills.
3. OPERATION
The term sluice gate refers to any gate that operates by
allowing water to flow under it. When a sluice gate is
fully lowered, water sometimes spills over the top, in
which case the gate operates as a weir.
Usually, a mechanism drives the sluice gate up or
down. This may be a simple, hand-operated, worm
drive or rack-and-pinion drive, or it may be electrically
or hydraulically powered.
4. Flow through a sluice gate differs fundamentally from flow through a
slot in that the jet is not free but guided by a horizontal floor.
Consequently, the final jet pressure is not atmospheric, but
distributed hydrostatically in the vertical section.
6. The water is now just starting to flow under the gate as it is slowly
being lifted upwards.
7. Here the sluice gate is open and letting the water flow through in a
controlled manner under the gate.
8. This is a picture of Leonardo da Vincis drop down sluice gate in
model form. He originally created it for a water course that was
divided into short sections by use of sluice gates with drop-down
pieces. It was used to make boats go up and down the water head
created by the crosspiece.
9. This is a picture of a sluice gate at Dolo. Here you can see how the
sluice gate in the lower right hand corner, helped to monitor the
flow of the river in the upper half of the picture.
11. FLAP SLUICE GATE
A fully automatic type, which is controlled by the
pressure head across it; operation is similar to that of a
check valve. It is a gate hinged at the top. When
pressure is from one side, the gate is kept closed; a
pressure from the other side opens the sluice when a
threshold pressure is surpassed.
12. VERTICAL RISING SLUICE GATE
A plate sliding in the vertical direction, controlled by
machinery.
13. RADIAL SLUICE GATE
A structure, where a small part of a cylindrical surface
serves as the gate, supported by radial constructions
going through the cylinder's radius. On occasion, a
counterweight is provided.
14. RISING SECTOR SLUICE GATE
Also a part of a cylindrical surface, which rests at the
bottom of the channel and rises by rotating around its
centre.
15. NEEDLE SLUICE
A sluice formed by a number of thin needles held
against a solid frame through water pressure as in a
needle dam.
16. LOGGING SLUICES
In the mountains of New England, sluices were used to
transport logs from steep hillsides to downslope
sawmill ponds or yarding areas. Nineteenth-century
logging was traditionally a winter activity for men who
spent summers working on farms. Water was applied
to logging sluices every night so a fresh coating of
slippery ice would reduce friction of logs placed in the
sluice the following morning.[
17. MINING APPLICATIONS
Sluice boxes are often used in the recovery of black
sands, gold, and other minerals from placer deposits
during placer mining operations. They may be small-scale,
as used in prospecting, or much larger, as in
commercial operations, where the material is first
screened using a trommel or screening plant. Typical
sluices have transverse riffles over a carpet, which trap
the heavy minerals, gemstones, and other valuable
minerals. The result is a concentrate.
