Yokohama Waterworks Commemoration Hall / Auxiliary stop cock1
Yokohama was the first city in Japan in which a modern waterworks system was constructed. The Yokohama Waterworks Commemoration Hall and Waterworks Technology Commemoration Hall displays materials and videos that present how Yokohama's waterworks system was developed. (For more information, see the February 2010 issue of the PR magazine pla-topia.) http://www.city.yokohama.lg.jp/suidou/kyoku/torikumi/suidou-pr/kinenkan/
An auxiliary stop cock is used to stop water during, for example, the replacement of faucet packing. The stop cock is housed in the meter box.
Handle-type stop cocks were replaced by lever-type stop cocks in 1983.
Until then, stop cocks were designed to stop water via the application of pressure on the packing. But these stop cocks were susceptible to the problem of wear in the packing.
Lever-type stop cocks adopt a ball valve in place of the packing. They no longer fail to open or close due to wear.
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Types of water meters | |
Plastic parts making up a tangential-flow-impeller water meter |
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Current tangential-flow-impeller type | |
Auxiliary stop cock |