Electrochemical investigations of high strength Stainless steels for rock and ground anchors

Stainless steel ground anchors are still rarely used in Europe. A project was initiated to demonstrate the technical and economic performance of stainless steels for such applications. Three different steel grades were examined, i.e. two austenitic grades 1.4311 (‘304LN’) and 1.4406 (‘316LN’) and one duplex grade 1.4362 (‘2304N’). All of them had low carbon contents (< 0.03%) and were alloyed with nitrogen to improve their strength properties. Different electrochemical tests were carried out to assess the performance of stainless steel in chloride/sulphate environments. The results confirmed that the investigated stainless steels may be employed for a wide range of corrosive ground anchor environments.     

INDUSTRIAL THROUGH-AIR DRYING OF NONWOVENS AND PAPER BASIC PRINCIPLES AND APPLICATIONS

The requirements for drying and thermobonding equipment working on the basis of the hot air flow-through system vary considerably due to the large variety of nonwovens qualities, production methods and required production speeds. It is therefore necessary to construct diverse drying systems in order to be able to offer appropriate machines for the desired purposes. Optimum heat and mass transfer from the penetrating air to the permeable material to be dried is ensured by through-air drying

Following Hans Fleissner's invention of the through-air system for drying of textiles and its practical application in the perforated drum dryer for more than 50 years a second engineering breakthrough for the paper and nonwovens industry has been achieved by Gerold Fleissner with the high-tech through-air drum

This paper presents various possibilities of air flow through the material and provide criteria to facilitate selection of the proper drying system