Note: When calculating buoyancy for liquids other than water, make adjustments in step 3.
5.5’’ Float (Non Weighted)
1. Weight of the 5.5’’ Float in air = 1.12 pounds
2. Volume of the displaced liquid = 87.12 cubic inches
4.189r3 Where r is float radius in inches
(4.189) (2.75)3 = 87.12 cubic inches
3. The weight of the displaced volume of liquid = 3.138 pounds
Water = 62.248 pounds/cubic foot
62.248/123 = pounds/cubic inch = 0.03602 pounds/cubic inch
(0.03602 pounds/cubic inch) (87.12 cubic inches) = 3.138 pounds
4. (Weight of the displaced volume of liquid) – (weight of the float) = total net buoyancy
(3.138 pounds) – (1.12 pounds) = 2.018 pounds, total net buoyancy
4.5’’ Float (Non Weighted)
1. Weight of the 4.5’’ Pipe Mount Float in air = 0.35 pounds
2. Volume of the displaced liquid = 57.73 cubic inches
3. The weight of the displaced volume of liquid = 2.08 pounds
Water = 62.248 pounds/cubic foot
62.248/123 = pounds/cubic inch = 0.03602 pounds/cubic inch
(0.03602 pounds/cubic inch) (57.73 cubic inches) = 2.08 pounds
4. (Weight of the displaced volume of liquid) – (weight of the float) = total net buoyancy
(2.08 pounds) – (0.35 pounds) = 1.73 pounds, total net buoyancy
The above calculations compare the 5.5’’ Stainless Steel Float Switch to the 4.5’’ Float Switch.
The larger 5.5’’ float displaces over 40% more liquid and has over 15% more net buoyancy.