Dear team members,
I need some help with an issue related to IGV . This IGV is installed at expander inlet. Control of this IGV is done using a cylinder with pneumatic circuit consisting of SIPART positioner. IA pressure provided to the cylinder/actuator is 6kg. There are two volume boosters installed on the cylinder/actuator. There is a magnetostrictive sensor to provide position feedback which is connected to the cylinder shaft. IGV movement is from -15deg to 8 deg. Offgas from our process is given to the expander through IGV. Offgas pressure is normally maintained at 1100 kPa and temperature is 145degC. Under no load condition, IGV works great, i.e. 0~100% movement as per the degree of movement. But when we connect it to the process, within a month IGV starts to malfunction. For instance, when the command is 100%, IGV should move up towards 8 deg but sometimes, it goes to -10 deg and gets stuck there. Surprisingly, the position feedback we get is 100% but physically, the IGV is close. This phenomena is very surprising and has been happening very frequently. Also we checked for any IA leakage and did not find any. Just as a precautionary measure, we changed all the IA accessories and cylinder/actuator during our last shutdown
Any help in troubleshooting is much appreciated.
I need some help with an issue related to IGV . This IGV is installed at expander inlet. Control of this IGV is done using a cylinder with pneumatic circuit consisting of SIPART positioner. IA pressure provided to the cylinder/actuator is 6kg. There are two volume boosters installed on the cylinder/actuator. There is a magnetostrictive sensor to provide position feedback which is connected to the cylinder shaft. IGV movement is from -15deg to 8 deg. Offgas from our process is given to the expander through IGV. Offgas pressure is normally maintained at 1100 kPa and temperature is 145degC. Under no load condition, IGV works great, i.e. 0~100% movement as per the degree of movement. But when we connect it to the process, within a month IGV starts to malfunction. For instance, when the command is 100%, IGV should move up towards 8 deg but sometimes, it goes to -10 deg and gets stuck there. Surprisingly, the position feedback we get is 100% but physically, the IGV is close. This phenomena is very surprising and has been happening very frequently. Also we checked for any IA leakage and did not find any. Just as a precautionary measure, we changed all the IA accessories and cylinder/actuator during our last shutdown
Any help in troubleshooting is much appreciated.