South African Class 8E 4-8-0 - AbsoluteAstronomy.com

In 1903, at the same time that the Cape Government Railways ordered its second batch of thirty-eight Class 8 4-8-0

4-8-0

Under the Whyte notation for the classification of steam locomotives, 4-8-0 represents the wheel arrangement of four leading wheels on two axles , eight powered and coupled driving wheels on four axles, and no trailing wheels. The type was nicknamed the Mastodon or Twelve-wheeler in North America....

Mastodon steam locomotive

Steam locomotive

A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...

s, four additional locomotives of the same class were ordered, but built to modified specifications in order to accommodate a larger grate area. In 1912, when these four locomotives were assimilated into the South African Railways, they were renumbered and reclassified to Class 8E.

Evolution

The first Cape Government Railways (CGR) Class 8 locomotive was a 2-8-0 Consolidation type designed by H.M. Beatty, the CGR’s Chief Locomotive Superintendent from 1896 to 1910. It was later to become the South African Railways (SAR) Class 8X

South African Class 8X 2-8-0

Between 1901 and 1902 the Cape Government Railways placed sixteen Class 8 2-8-0 Consolidation type steam locomotives in service. In 1912, when they were assimilated into the South African Railways, they were renumbered and reclassified to Class 8X...

. While these first Schenectady and ALCO built 2-8-0 locomotives were being subjected to exhaustive testing on all types of traffic and under varying conditions, some trouble was experienced with the leading two wheeled pony truck and, when designs were prepared at Salt River for a later order for more locomotives, the pony truck was replaced with a four wheeled bogie, resulting in the CGR’s 4-8-0 Mastodon type Class 8.

In spite of the difference in wheel arrangements, the CGR’s 2-8-0 Consolidations and post Class 7 4-8-0 Mastodons were all grouped together into Class 8.

Builders

In 1902, when a second batch of thirty-eight Class 8 4-8-0 locomotives were ordered, later to become the Class 8D

South African Class 8D 4-8-0

In 1903, when the first batch of Class 8 4-8-0 Mastodons had been tried and proven successful, the Cape Government Railways placed another thirty-eight Class 8 4-8-0 steam locomotives in service, six on the Cape Western System, twenty on the Cape Midland System and twelve on the Cape Eastern System...

on the South African Railways (SAR), an additional four locomotives were ordered. These were of an experimental design, to be built to modified specifications.

Beatty believed that, while the earlier Class 8 locomotives (later the SAR Class 8

South African Class 8 4-8-0

In 1902 and 1903 the Cape Government Railways placed twenty-three Class 8 steam locomotives with a 4-8-0 Mastodon wheel arrangement in service, three on the Cape Western System, eight on the Cape Midland System and twelve on the Cape Eastern System...

) steamed well, they would steam even better if they had a larger firegrate area. He was hampered by the fact that the firebox wrapper plates had to fit between the rear coupled wheels, but he overcame that by designing a Class 8 locomotive with a deep curve in the foundation ring, or mud ring, to clear the intermediate coupled wheels, and a steep slope to the back to clear the trailing wheels. In the process he was able to increase the firegrate area from 21 to 27.5 sq ft (2 to 2.6 m2).

The locomotives were ordered from Neilson, Reid and Company and delivered in 1903. They were numbered 813 to 816 and allocated to the Cape Western System of the CGR.

Class 8 sub-classes

When these four locomotives were assimilated into the newly established SAR in 1912, they were renumbered 1230 to 1233 and reclassified to Class 8E.

These locomotives, together with the rest of the CGR’s fleet of Class 8 2-8-0 Consolidations and Class 8 4-8-0 Mastodons, plus the Class 8-L1 to 8-L3 4-8-0 Mastodon locomotives from the Central South African Railways

Central South African Railways

From 1902 to 1904, the area of power of Lieutenant-Colonel Sir Percy Girouard later also included the lines of The Netherlands-South African Railway Company; together this dominion covered all lines in the Transvaal that belonged to NZASM ....

(CSAR), were grouped into ten different sub-classes by the SAR. The 4-8-0 locomotives became SAR Classes 8 and 8A to 8F and the 2-8-0 locomotives became Classes 8X to 8Z.

Reboilering

With no appreciable gain obtained in steaming capacity, the enlarged grate area on these experimental locomotives did not come up to expectations. Since the fireboxes started having problems with cracks and leaking rivets soon after the locomotives were placed in service, the experimental boilers and fireboxes were soon replaced with normal Class 8 boilers and fireboxes.

Superheating

During A.G. Watson’s term as the Chief Mechanical Engineer (CME) of the SAR from 1929 to 1936, many of the Class 8 to Class 8F locomotives were equipped with superheated boilers, larger bore cylinders and either inside or outside admission piston valves. The outside admission valve locomotives had their cylinder bore increased from 18.5 to 19 in (469.9 to 482.6 mm) and retained their existing SAR classifications, while the inside admission valve locomotives had their cylinder bore increased to 20 inches (508 mm) and were reclassified by having a "W" suffix added to their existing SAR classifications.

Of the four Class 8E locomotives, numbers 1232 and 1233 were equipped with superheated boilers, 19 inches (482.6 mm) bore cylinders and outside admission piston valves while retaining their Class 8E classification.

Service