How Many Blanks Does One Coil Make?
Enter a coil and a blank, and see how long the coil is, how many blanks it makes, and how many coils your order takes.
How It's Calculated
- Coil length, in
- coil weight ÷ (coil width × gauge × 0.2836)
- Outside diameter
- √(inside diameter² + 4 × length × gauge ÷ π)
- Weight per inch of width
- coil weight ÷ coil width
- Blanks per coil
- ⌊(length − ends lost) × blanks per inch of the best layout⌋
- Coils for the order
- ⌈quantity ÷ blanks per coil⌉
Related: How a Coil Becomes Blanks · Nest Calculator
Questions About Coils
How do you find the length of a steel coil?
Divide the coil's weight by the weight of one inch of its length: width × thickness × 0.2836 lb per cubic inch for carbon steel. A 40,000 lb coil 60 in wide in 0.105 in steel is about 22,400 in, or roughly 1,870 ft.
What is PIW?
Pounds per inch of width: the coil's weight divided by its width. Mills, service centers and press lines use it to set coil weight limits, because a coil's handling and its load on an uncoiler both scale with it.
Why are some blanks lost at each end of a coil?
The head of a coil has to be threaded through the straightener and into the die, and the tail runs out before the last full blank. The steel in between is often off-flat or marked, too. How much is lost depends on the line, so enter your own figure.
How do you find a coil's outside diameter?
The steel wound on a coil fills a ring between the inside and outside diameters. Its area, π ÷ 4 × (OD² − ID²), equals the coil's length times its thickness, which gives the outside diameter.