Yes, but that pressure acts against that plate you are trying to slide upwards.

1/2 psi * 15 = 7.5 psi.

Area of a circle is pi * radius squared, so the 8 inch circle is 3.1415 * 4 *4 = 50 square inches.

7.5 psi * 50 = 375 pounds pushing against the plate, making it harder to slide the gate upwards. Perhaps it take 100 pounds? I have no idea but you might ask.

That's all assuming its a gate you pull up on to open.

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