Innervalve guiding / Top - Medium - Heavy
Standard top guided:
A top guided innervalve is stem guided at the packing. Some innervalves, due to the inherent close fit between the plug and seat, could also be considered "seat guided".
A medium guided trim is guided at the packing and in the bonnet. The medium guided style was developed to provide a guide option to those wishing to use Standard bonnets rather than the heavy duty version. Medium guided trims, when available, will fit standard bonnets.
Heavy duty guided:
The heavy duty guide provides maximum resistance to actuator forces and pressure induced vibration. The bonnet and trim will not interchange with the standard bonnet designs.