What is roll formula?

Figure out the length of a roll of paper by knowing the diameter of the paper roll, the thickness of the paper and the dimension of the center hole. Multiply the roll of the diameter by 3.14159. This is the roll circumference in lineal inches. Multiply the core diameter by 3.14159.

How do you calculate roll rpm?

To calculate RPM for an AC induction motor, you multiply the frequency in Hertz (Hz) by 60 — for the number of seconds in a minute — by two for the negative and positive pulses in a cycle. You then divide by the number of poles the motor has: (Hz x 60 x 2) / number of poles = no-load RPM.

How do you calculate roll length?

We can use the ruler to measure the paper roll width, diameter, core size:

A: paper width.
B: paper diameter.
C: core outer size.
T: paper thickness.
L: paper roll’s length.
A × L × T = πB²A ⁄ 4 – πC²A ⁄ 4.

How do I calculate my roll weight?

To find the approximate weight of a roll, multiply roll diameter squared minus core diameter squared by roll width and appropriate factor.

What is a rolling used for?

Rolling is the most widely used method of shaping metals and is particularly important in the manufacture of steel for use in construction and other industries. Rolling may be done while the steel is hot (hot-rolling) or cold (cold-rolling).

Which is the correct formula for rolling process?

=2R (1-cosα) 5.1 Where d = draft, mm (in); = starting thickness, mm (in); and = final thickness, mm (in).R = roll radius in mm and (α) = bite angle in degree. Draft is sometimes expressed as a fraction of the starting stock thickness, called the

How to calculate the required power for Rolling?

For actual power requirement we have consider the HOT ROLLING THEORY and calculated the required power and torque for rolling process. 2.

What’s the difference between cold and hot rolling?

In cold rolling, the value is around 0.1; in warm working, a typical value is around 0.2; and in hot rolling, m is around 0.4. Hot rolling is often characterized by a condition called sticking, in which the hot work surface adheres to the rolls over the contact arc. This condition often occurs in the rolling of steels and high-temperature alloys.

How do you calculate the roll separating force?

The roll separating forces at the drive side and operator side may be different. They are obtained by balancing the force and moment of the roll system: PL =roll separating force at the left side (drive side); P1 =total rolling force; Fl =work roll bending force on the left side (drive side);