2. Water Process & Treatment ① Well Screen

 

① Well Screen.

KOREA SLOT well screen is a filtering device that serves as the intake portion of wells constructed in unconsolidated or semi-consolidated aquifers. The screen permits water to enter the well from the saturated aquifer, and prevents sediment from entering the well, and serves structurally to support the aquifer material. The importance of a proper well screen cannot be overlooked when considering the efficiency of a well and the log-term cost.

Well screens are manufactured from a variety of materials. The value of a screen depends on how effectively it contributes to the success of a well. Important well screen criteria and functions include:

Criteria:

1. large percentage of open area

2. non clogging slots

3. resistant to corrosion

4. sufficient column and collapse strength

Functions:

1. easily developed

2. minimal incrusting tendency

3. low head loss through the screen

4. control sand pumping in all types of aquifers

Continuous-slot well screens provide more intake area per unit area of screen surface than any other types of screen. This type of screen has maximum open area. For best well efficiency, the percentage of open area in a screen should be the same as, or great than, the average porosity of the aquifer material. Water flows more freely through a screen with a large intake area compare to one with limited open area. The entrance velocity is low, therefore head loss for the screen is at a minimum and finally minimizes draw down in the well.