*Tractive
Effort Calculation for 4 Cylinder Compound 'Argentina'*

**Note:
**The figures presented below have been rounded to 3 decimal points to
simplify presentation so may not give the precise answers shown when checking
the figures. However these answers are valid when working to a higher number
of decimal places.

The following lines of calculation as based on the formulæ given in 1936 by E.A.Phillipson in the book "Steam Locomotive Design: Data and Formulæ."

The formula used, which applies ONLY to 4 cylinder compound steam locomotives states:

**Tractive
Effort = 2(DxD)Sp / (R+1)W**

Where:

D
= Low Pressure Cylinder Diameter.

S= Low Pressure Cylinder Stroke.

p = Receiver Pressure.*

R = Area of High Pressure Piston / Area of Low Pressure Piston.

W = Diameter of Driven Wheels.

*In addition it is stated that p shall be calculated thus:

**p = P /
(R+1)**

Where:

P: Boiler Pressure multiplied by 0.8

Therefore in the case of 'Argentina' the figures, calculated in Imperial measures, are:

D = 22.835"

S = 22.047"

DxD = 521.418"

High Pressure Cylinder Area squared = 200.879

R = 521.418 / 200.879

= 0.385

p = (285x0.8) / (0.385+1)

= 228 / 1.385

= 164.590psi

TE = (2x521.418x22.047x164.590)
/ 1.385x50

= 3784199.078 / 69.262

= **54635.384lbs**

Conversion from Imperial to Metric:

1lbs force = 0.004 kN

54635.384x0.004
= **243kN**