Which property is critical for calculating the pressure needed to cut steel in hydraulic shears?

The critical property for calculating the pressure needed to cut steel in hydraulic shears is shear strength. Shear strength refers to the maximum stress that a material can withstand while being cut along a particular plane before it yields or fractures. In the case of hydraulic shears, the tool must generate sufficient pressure to exceed the shear strength of the steel being cut.

This means that when determining the appropriate pressure requirements for effective cutting, understanding the shear strength of the material being processed allows for proper design and operation of the hydraulic system. The actual pressure applied by the hydraulic shears must overcome the shear strength to successfully perform the cut, which is why this property is fundamental in calculations.

While piston diameter can influence the force exerted by the hydraulic system, it is not the primary factor in determining the pressure required for cutting. Fluid viscosity and fluid temperature are important in terms of the efficiency and behavior of the hydraulic fluid, but they do not directly dictate the amount of pressure required to cut through the material.