Bi-stable latching valves are an energy-efficient alternative to mono-stable switching valves especially in applications of process technology requiring low switching frequencies. However, the bi-stability of such valves may be disadvantageous, since external forces can change the valve state randomly without being noticed by the controller. Condition monitoring by using position estimation method enables a valve state determination and thus, safe cost- and energy-efficient bi-stable valves as alternative to mono-stable switching valves.
The paper shows an implementation of a periodic determination of the valve’s state into a cost-efficient electronics for commercial use. Differential inductance method serves as position estimation method, which requires only a voltage and current measurement. Different methods for its calculation are performed and investigated in a realistic environment by using a fluid operated valve.

Modern hydraulic systems of mobile machines are requiring components with new control structures, in order to be compatible with the modern networks of the future. The new generation of electro-mechanic valve actuation technology of Sonceboz is presented in this paper. Compared to the previous actuator, the performance has increased significantly. Moreover, the new control concept enables a wide range of connectivity and on-board diagnostic features. The result is a high innovative valve actuation system with online diagnostic functions that can operate in a network with decentralized intelligence. Therefore, supporting hydraulic valve manufactures to meet the challenges for the highly connected systems of tomorrow.

The presentation will introduce special hydraulic fluids, with which fluid technology solutions for complex
requirements, especially exceptional stresses, boundary lubrication, can be offered.
Newly developed hydraulic fluids for high-pressure operations are presented, which will meet the increased
requirements of redesigned pump tests and test field trials. In this case the respective material combination and
the additivation which is adjusted to the pressure and temperature level, plays a decisive role.
Moreover special hydraulic fluids, latest application-specifically adjusted development trends and a short
overview of the main base oil and additive trends are mentioned.

Hydraulic cylinders are some of the hydraulic components which convert the energy into force and / or movement at the end of the hydraulic circuit. Side loads can occur, which must be absorbed by guide elements. A simplified FEM-based calculation method and test methods of plastic guide rings are described, depending on various parameters (material, deflection, angular misalignment, geometrical conditions, etc.). For the product developers, material-specific prognosis of the guide elements behaviour are possible, regarding stresses, strains and load-bearing capacity of the guide elements, considering the specific dimensions and general conditions, due to a company-internal, parameterized FEM tool. In consequence of an optimized design, the number or the width of the guide elements in a cylinder can possibly be reduced, the resulting advantage could be a shorter length of the cylinder components and corresponding cost reduction.