Georg Zanner

Siemens Valve Performance Concept 

As a turnkey supplier of nuclear and fossil power plants, Siemens must pay attention in concentrating, maintaining, and developing the expertise in many areas such as system design, components, materials, quality assurance, and qualification testing within centralized organizations. In the company segment VALVES, Siemens/ KWU is staffed with experienced professionals who have serviced the power plant industry for about 30 years.

The valve engineers deal with all kinds of valve and actuator-related activities like design ratings, development, qualifications, and ongoing improvements. In this regard, the engineers are involved in nearly all actual problems and suggested solutions through continuing dialogues with utilities, authorities, and vendors of valves and actuators.

Siemens valve departments are familiar with all valve types (e.g., globe butterfly, check, control, safety, and relief valves) and vendor-specific problems. The valve engineering has reviewed or participated in various testing and improvement programs:

Siemens has used the knowledge gained in valve engineering and testing to develop an EXPERT SYSTEM to justify the change from preventive to condition-oriented maintenance. The goal is an integral valve „service concept“ which includes a PC-based „trending method“ and quantifies measured and calculated valves.

The program tells the user if the valve performs still within accepted margins and, if not, which action (i.e., maintenace) has to be taken.

The steps of the Siemens Valve Service Concept are:

The results indicate the readiness for function and parameter for condition oriented maintenance. A graphical example of the concept, for a globe valve is shown in Figure 1.