HOME ABOUT US PRODUCT CHOOSING SCREENS CASE HISTORY NEWS CONTACTS LANGUAGES CHOOSING SCREENS Home • Choosing screens CHOOSING SCREENS FOR WATER WELLS The choosing of screen slot dimensions for water wells depends essentially on the gravel pack grain-size distribution and this latter dependes on the grainsize distribuzion of the water-beraing soil. In case of wells where it is not possible to have an artificial gravel pack (rotary drilled wells) it is neessary to choose the screen so that 30-40%of the water-bearing soil can be extracted in order to make an area of high permeability around the screens; therefore, the size of the slots must be nearly equal to the valve d30 - d40 on the soil grain-size distribution. In case of artificial gravel pack, there are various methods, but the easier one is the following: multiply the value d30 by 4 if the soil is fine and homogeneous (U < 2,5), by 6 if the soil is big and heterogeneus (U> 2,5) and by 9 if the soil is fine and heterogeneus; dans the value obtained on the same diagram in corrispondence with d30 and the trace a grain-size line passing throught this point and having a value of U< 2,5 for soil U>2,5 or U=2,5 for soil U>2,5. The screen slots for water wells must be such as to retain not less than 90% gravel, that means it is necessary to have b<= D10 PAPARELLI ALESSANDRO & FIGLIO SRL Address: Via Molino Geretto, 8 22060 Carimate (Como) Italy Phone: +39 031 790601 Fax: +39 031 791460 Email: info@paparelli.it P.Iva: 00607900131 REA: 153340 Como Cap. Soc. € 60.000 i. v. In May 1998 Paparelli certified its own quality system accordingly to the rule UNI EN ISO 9002 and since 2003 to the rule UNI EN ISO 9001:2000; currently it has been updated according to the rule UNI EN 9001:2015. Quality Policy Privacy policy Cookie policy NewVisibility Design SPONSOR OF: We use cookies to ensure that we give you the best experience on our website. Our website uses cookies, which could include also third party cookies. If you want to find out more about the cookies we use and how to disable them, you can access our Cookie Policy By continuing your visit on the website, you consent to the use of the cookies.I AGREE