LENGTHS

Inches x 25,4001 = millimetres

Inches 0,0254 = metres

Feet x 0,30480 = metres

Yards x 0,91440 = metres

Feet x 0,000 30480 = kilometres

Statute Miles x 1,60935 = kilometres

TORQUE

Kilogram force Metre (kgf.m) x 9.81 = newton metre (N.m).

Pound Feet x 1,36 = newton metre (N.m).

Pound Inches x 0,113 = newton metre (N.m).

FORCE

Kilogram force x 9,81 = newtons (N).

Pound force x 4,45 = newtons (N).

The kilopond (Kp) is an alternative name for Kilogram force (kgf).

SYMBOLS USED

r/min = revolutions per minute.

m/s = metres per second.

TORQUE AND POWER EQUIVALENTS

The kilowatt (kW) is the common unit of mechanical power, i.e. the rate of doing work.

Torque is a turning moment or twisting effort and is expressed in newton metre (N.m).

INERTIA

Pound feet squared (lbf.ft²) x 0,413 39 = newton metre squared (N.m²)

POLAR MOMENT OF INERTIA

The polar moment of inertia. I or flywheel effect of a solid cylinder, disc or hollow cylinder can be derived from the following formula:

For a disc or cylinder, 1 = 0,5 m.r²

Where m is the mass of the disc or cylinder and R and r are the outside and inside radii respectively.

PERIPHERAL SPEED

where:

s           =         belt speed… m/s

d          =         pulley pitch diameter… mm

n          =         rotational speed… r/min

TEMPERATURE

Where:

°F = degrees Fahrenheit.

°C = degrees Celsius.