Happy New Year starts with a EPS new build of a STAR valve assembly – STG2120 – E30-90 – APU and ECU spares

EPS has assembled a new STG2120 STAR valve for a gas turbine company and is due to test this on our rig next week.

EPS can support all site interventions and the supply of parts for the STAR valve family. We hold stock of various key components and can test, repair and supply many others.

Parts are becoming hard to source and EPS does recommend replacement of the STAR valve with something that is current and supportable. Check out our article on the GS16 retrofits that we can supply – GS16 Retrofit

Siemens STAR valve

The Siemens STAR system compromises of a electric actuator, precision ball valve, APU (actuator positioner unit) and ECU (electronic control unit). The controls system sends a kW demand out to the ECU and this takes care of positioning the valve, and also monitoring its feedback etc. Heinzmann

This is an inherently complicated system with many components to go wrong. Typically the ECU is in the field which means it is susceptible to water ingress.

The feedback was originally done by an internal feedback pot, later moved to an external one. These are wiper, contacting type potentiometers which means that they wear over time. Especially on a gas turbine which typically runs in the same region for 95% of its operation.

With the EPS GS16 retrofit, all these problems disappear. The reliable actuator has a digital encoder and the ECU functionality is built into the PLC software.