Rising stem and non-rising stem gate valves differ primarily in their stem movement and structural design:

1. ‌Stem Visibility and Movement‌

   • ‌Rising stem‌: The stem moves upward when the valve opens, making its position visible. The drive thread is outside the valve body, allowing direct observation of the valve's opening/closing status‌.
   • ‌Non-rising stem‌: The stem remains stationary; only the disk moves, with the drive thread inside the valve body. The stem rotates but does not rise, making it less intuitive to gauge the valve's position‌.

2. ‌Space Requirements‌

   • ‌Rising stem‌: Requires more vertical installation space due to the upward stem travel‌.
   • ‌Non-rising stem‌: Compact in height, suitable for confined spaces‌.

3. ‌Lubrication and Maintenance‌

   • ‌Rising stem‌: The exposed stem facilitates easier lubrication and maintenance‌.
   • ‌Non-rising stem‌: Lubrication is more challenging as the stem is internal‌.

4. ‌Application Suitability‌

   • Both types are linear motion valves, typically used fully open or closed, not for flow regulation‌.
   •