Outside Screw Gate Valve

Stem threads are not exposed to the fluid, and valve opening operation moves the stem upwards while the handwheel stays at the same position. The Valve operating position can be visually determined by observing the stem travel KITZ Fig.
FCM, FCL, FCLS, and FCLU are designed this way.

Outside Screw Globe Valves

The stem and handwheel move upwards or downwards at the same time, following valve opening or closing operation.
All KITZ globe valves are provided with this design.

Inside Screw Gate Valve

Stem threads are exposed to the fluid. Opening the valve does not make the stem or handwheel move. Thus, the valve operating position is not visible. A position indicator is provided for this reason.
Inside screw gate valves are generally designed shorter than outside screw gate valves and the stem and handwheel always at the same position. For this feature, inside screw gate valves are widely employed for underground installation or service in narrow areas with limited room. KITZ Fig. FCWI and FCHI are designed this way.