Hydraulic presses can exert many thousands of pounds of force, making them useful for industrial operations such as forming metal parts. The pressure in the press’s hydraulic system is typically measured in pounds per square inch, which is force per unit area. To calculate the force produced, multiply the pressure by the area of the hydraulic cylinder’s piston in square inches. This will give you the force in pounds, which you can easily convert into tons.

Reference the necessary data, such as psi and cylinder piston diameter or area. This information should be offered in the hydraulic press's specification sheet.

Calculate the area of the cylinder piston, if it is not offered on the specification sheet. Use the formula: Area equals 3.14 times the square of the diameter, divided by four.
As an example, If the piston diameter is 4 inches, then you would multiply 3.14 times 4 inches times 4 inches, divided by 4. Therefore, the area is 12.56 square inches.

Multiply the pressure rating, in psi, by the area. In the example, if the press offered 2,500 psi, then you would multiply 2,500 by 12.56. This gives you 31,400 pounds.

Divide the number of pounds by 2,000 to convert to tons. In the example, 31,400 divided by 2,000 gives you a force of 15.7 standard tons.
If you wish to convert to metric tons, you would divide by 2,205. In the example, 31,400 divided by 2,205 gives you a force of 14.24 metric tons.
References
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