Siemens SITRANS L Application Examples page 8

Guidelines
• A vent hole must be provided near the top to prevent an air lock.
• Slots or holes in the pipe should be at least smaller than 1/10 of the diameter of
the pipe.
Slots or holes are common in pipes in the hydrocarbon industry to accommodate
either for the fact that the material in the tank isn't homogeneous, or water could be
present at the bottom of the tank. Slots or holes will prevent the liquid from being
sucked in from the bottom.
• An angled plate welded to the bottom of the pipe will improve measurement
accuracy at the bottom of the tank for very low dielectric liquids.
Please refer to the accompanying illustration.
8
Using SITRANS LR in a Stilling Well
Application examples, 04/2020, AG070814