Basic material

Stainless steel, different qualities depending on ground water properties and temperature.

Steel - mild steel, preferably S235JR or similar steel with good weldability properties. Suitable for drawdown wells. Not approved for drinking water.

Steel - galvanized, S235JR as base material. Only suitable to a limited extent for contact with drinking water.

Steel - coated plastic, S235JR as base material, Rilsancoated, approved for drinking water. Meets the KTW recommendation of the German Federal Department of Health.

Properties and suitability of stainless steel

M No. 1.4301 (X5CrNi18-10), AISI 304
This type of steel is resistant to water and slightly polluted waste water as well as weak organic and inorganic acids. Generally it is resistant to a pH value up to approx. 4.5 in aggressive substance low in chloride.

M No. 1.4306 (X2CrNi19-11), AISI 304L
Similar properties as 1.4301 but with lower carbon content, resulting in an increased resistance to intergranular corrosion, which can occur, e.g. during the welding process.

M No. 1.4307 (X2CrNi18-9), AISI 304L
Similar properties as 1.4306 but with slightly lower Ni content.

M No. 1.4541 (X6CrNiTi18-10), AISI 321
Stainless steel has excellent resistance properties to a variety of aggressive media. Furthermore, this material is characterised by a good ductility.

M No. 1.4404 (X2CrNiMo17-13-2), AISI 316L
Better general resistance compared to 1.4301, 1.4306, 1.4307 and 1.451, particularly in case of increased chloride content. Resistance to intergranular corrosion is ensured by limiting the carbon content.


M No. 1.4571 (X6CrNiMoTi17-12-2), AISI 316Ti
Similar properties as 1.4404 but with guaranteed resistance to intergranular corrosion due to titanium content.

M No. 1.4462 (X2CrNiMoN22-5-3) Duplex

This duplex steel is characterised primarily by its high pitting and stress corrosion resistance in neutral and chlorinecontaining media resulting in good resistance to seawater.

M No. 1.4539 (X1CrNiMoCuN 25-20-5)
High resistance to phosphorus and sulphuric acid media with simultaneous chloride contamination.

Additional material grades available on request