Sluice-gate.
（
Hydraulic Engineering.)
a. Lock-gates of canals are provided with sluice-gates, as are also the sluice-walls in other structures where a flush is obtained by the sudden releasing of the pent — up water.
The sluice-gate is a simple plate, which covers the opening, and is raised or lowered by means of a rackbar and pinion.
See flushing.
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Sluice-gate. |
Brunot's (
Fig. 5215) is more particularly designed for application to dams erected for purposes of slack-water navigation, and is intended to be available when, in floods, the water has risen to such a hight over the head of the dam that the locks cannot be made use of. In the form illustrated, it consists of a hollow structure of timber or plate-iron.
D D placed within a pit or chamber in the dam
A B, which, as shown, is of crib-work filled in with stone, but may be of masonry.
At each end of the pit is a well
E E provided with a gate
l l′, one of which communicates with the up-stream and the other with the down-stream side of the dam, and is raised or lowered by the shafts
m m or other contrivances.
The gate
D D is also provided with valves, which are opened or closed to admit or withdraw water as required.
At ordinary stages of water, it is retained at a level with the head of the dam and assists in retaining the water behind it; but when the river has risen to a considerable bight above the dam, one or more of the valves are opened, permitting the water to flow into the gate, which sinks, leaving the sluice open so that it
[
2219]
may afford a passage for boat.
When the gate
D D is to be raised, the gate
l′ of the down-stream passage of the well
E is opened and the other gate
l of the up-stream passage is closed, permitting the water to flow wholly or partially out of the pit, and the appropriate valve in the gate
D D is also opened, allowing water to escape from and air to enter it, so that it will float.
The valve is then closed and the action of the gates
l l′ reversed, again filling the pit with water, upon which the gate
D D rises and closes the sluice as before.
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Sluice-gate for water-wheels. |
b. The gate which admits water to the scroll-chute of a water-wheel.
In the example, this is worked by rack and pinion.
