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水ポンプ DAYLIFF D3SPのPDF インストレーション＆オペレーティングマニュアルをオンラインで閲覧またはダウンロードできます。DAYLIFF D3SP 16 ページ。 Submersible borehole pumps

ii) Pump Position

Borehole Measurement Parameters

L1.Minimum

dynamic water level

L2. Depth to dynamic water level (DWL)

L3.Depth to static water level (SWL)

L4.Draw down. This is the difference

between the dynamic and the static

water levels

L5. Installation depth

L6. Distance of pump from well bottom

When positioning the pump it is important to ensure adequate motor cooling

through water flow past the motor. This will be achieved by installing the pump

suction above the borehole main aquifer or well screen and if not possible or in

cases of open water installation a cooling sleeve must be used. Recommended

minimum flow rate past the motor is 0.2m /sec.

It is recommended that the complete pump is submerged at least 3m the

dynamic water level and if possible the pump should be installed at least 3m

from the bottom of the borehole to prevent silting damage. As a rule the pump

should be positioned mid-way between the bottom of the borehole and the

dynamic water level assuming that the main aquifer is below this level. If in doubt

consult the pump supplier.

It is recommended that a fully equipped borehole service vehicle be used for

pump lowering and removal in order to minimize risk of pump dislodging.

However, for shallow boreholes (less than 50m) a manual tripod arrangement

can be used. When moving the pump the following procedures should be

followed:-

Before starting pump lowering it is important to check the borehole depth and

straightness to ensure it is as expected and there is unobstructed passage.

The pump should be carefully lowered into the borehole and if an

installation depth below

Fig. 4 Borehole Measurements