Economical reasons lead to the demand in the early days in Germany to develop materials and products, which can extend the lifetime of wells in order to reduce the operation costs for service, repairs and rehabilitation. The chain of development is from steel screens, galvanised screens, coated steel screens (Hagulit), to none-corrosive materials like the different grades of stainless steel ( wire wound screens and Bridge slotted) and thermoplastics like PVC and HDPE. Depending on the geological, mechanical or chemical properties the materials are used for deeper or shallow wells and for water sources with higher or lower salinity.
For corrosive groundwater stainless steel or PVC casing and screens is recommendable. For short-term construction, like in dewatering projects black steel und galvanized material are used.
For wells with water layers of less than 200 ? 300 m depths PVC material is used, for deeper wells steel material will be selected in case the mechanical strength is required.
Specially for water layers with high percentage of fine sand the use of wire wound screens (Vent-Screen®),is recommendable for hydraulic reasons and for sandfree production. Vent-Screen&Mac 226; - Made in Germany ? is a high-end product which has its market in water wells but also with an increasing share in the Oil & Gas industry.
Due to great variety of products it is recommendable to ask already during the project phase for the advise of the experts.
