Hard Chrome Plating Training Course

Table of Contents

Appendix 4. Calculation of Surface Area and Volume

Formula:

Surface area = width (w) x length (l)

Example:

A flat surface to be plated is 1.5 feet wide by 2.0 feet long. What is the surface area of one side?

surface area = 1.5 feet x 2.0 feet = 3.0 ft³

Convert to square feet to square inches:

3.0 ft² x 144 in/ft² = 432 in³

Formula:

Volume = width (w) x length (L) x height

Example:

A plating tank is 3.0 feet wide by 6.0 feet long by 4.5 feet deep. What is the volume of the tank in gallons?

volume = 3.0 ft x 6.0 ft x 4.5 ft = 81.0 ft³

Convert cubic (ft³) feet to gallons:

81.0 ft³ x (7.48 gal/ft³) = 605.9 gallons

Surface area = π x diameter (d) x height (h) or 3.14 x d x h

Note that π always equals 3.14.

With this formula, we do not include the ends of the cylinder because they are normally not plated.

Example 1:

A piston is 30 inches long and has a diameter of 4 inches. What is the surface area of the piston?

surface area = (3.14) x (4 inches) x (30 inches)

surface area = 376.8 in²

Example 2:

An inside journal is 1.5 inches long and has a diameter of 4 inches. What is the surface area of the journal?

surface area = (3.14) x (1.5 inches) x (4 inches)

surface area = 18.8 in²

Volume of a Cylinder

Volume = π x (radius)² x height

where radius (r) = d/2

Example: Volume of Partially Filled Drum

A 55 gallon drum with a diameter of 23 inches contains 14 inches of sulfuric acid. How many gallons of sulfuric acid are in the drum?

Volume = (3.14) x (23/2)² inches x 14 inches Volume = 3.14 x 132.25 x 14

Volume = 5,813.7 in³

Convert to cubic feet:

5,813.7 in³ ÷ 1,728 in³/ft³ = 3.36 ft³

3.36 ft³ x 7.48 gal/ ft³ = 25.2 gal.

Appendix 5