**Pounds per Square Inch (psi) and MegaPascal (MPa) or N/mm2 conversions.**

Pounds per Square Inch (abbrev. PSI) - A basic unit of pressure or tension measurement in the Imperial or English System of Weights and Measures.

1 psi = .006895 MPa,

1000 psi = 1 ksi

MegaPascal (abbrev. MPa) - A basic unit of pressure or tension measurement in the International System of Weights and Measures.

1 MPa - 145 psi,

1 MPa = 1 N/mm2.

For oil field applications, units of measurement smaller than 1 psi usually have little meaning. Units of MPa may often appear with a decimal.

Example: 1000 psi = 6.895 MPa.

1 MegaPascal (MPa) = 1 Newton per Square Millimeter (N/mm2) = 145 Pounds per Square Inch (psi).

Psi, Ksi, MPa, and N/mm2 all express force measurement, either pressure (as fluid pressure) or load (as tension).

All of these terms may appear as pressure ratings or test pressures, and tensile or yield requirements or test results.

To express Psi pressures in bars, convert Psi to MPa and move the decimal in the MPa value 1 space to the right, e.g. 5000 Psi = 34.5 MPa = 345 bar.

Kilogram (abbrev. kilo) - The fundamental unit of weight measurement in the International System (or Metric System) of Weights and Measures.

This system expresses weights lighter than a kilogram in grams (1 kilogram = 1000 grams).

**Pound**** and kilogram weight conversions.**

Pound (abbrev. lb) - The basic unit of measurement in the Imperial or English system of weight measurement.

The Imperial system expresses weights lighter than a pound in ounces (1 pound = 16 ounces).

The term "Ton" = a pound weight of 2000 pounds (also called Short Ton).

**Oil field "Ton" capacity equipment rated in 2000 pound Tons.**

The term "Long Ton" = a pound weight of 2204.6 pounds. Technically used to represent the displacement of large ships.

The term "Tonne" (abbrev. MT) only applies to weights of 1000 kilograms.