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消火器 DUKER 304のPDF 取扱説明書をオンラインで閲覧またはダウンロードできます。DUKER 304 14 ページ。 Underground fire hydrants

10. Maintenance and trouble shooting

Consider this chapter always together with chapter 5.5 (Operation)

Regular maintenance intervals on hydrants are not required. We recommend to control the

function, drainage and tightness of the hydrant at the latest every 4 years.

We refer to the DVGW Leaflet W 392, Table 2, No. 2.

When flushing the hydrant, in any case the use of a standpipe with connected hose to

discharge the flushing water is necessary. Never flush the hydrant free into the surface box.

In case of flushing of the hydrant without standpipe, dirt and pollution from the surface box

can be sluiced into the hydrant and create problems with the water hygiene or plugging the

drainage outlet.

To avoid the generation of to high pressure in the upper part of the column, never close the

hydrant while the side valves of the standpipe are closed.

Furthermore please observe the procedure for the operation of underground fire hydrants,

which is given in annex "A" of the DVGW Leaflet W 331.

Turning the stemcap anti-clockwise will open, whereas turning clockwise will close the

hydrant.

To operate the hydrant the use of operation keys according to DIN 3223 is recommended.

The keys are designed to ensure that normal manual force is sufficient for operation.

The additional use of key extensions to increase the operation torque s not allowed as this

will damage the valve internally.

Hydrants are open-close valves and not designed to regulate the water flow. To avoid

excessively high flow verlocities or cavitation, the obturator should always be opened up to

the mechanical end stop "Open" even during flushing. As a rule, the side valves of the

standpipe or distributor must be used to regulate the flow rate.

=> Throttling or intermediate positions of the obturator during water flow are not

allowed!

To guarantee the proper function and the adherence to the hygienic

requirements for potable water, the use of Düker genuine spare parts is

stipulated.

The distribution and reproduction of these Operating Instructions, utilization and communication of their contents to

others is authorized exclusively for the purpose of ensuring the correct installation and operation of the Düker product

treated in the document. For all other purposes, distribution, reproduction and utilization of the contents, also in

the grant of a patent, utility model or design.

01/042017

Düker GmbH, www.dueker.de