Class 634A
3-Cylinder
Compound Goods Locomotive
Designed by Jochann
Ketterik
Built in 1964 by RSR
Works, Bevice-Akohniçe, Ruhnia
Although the 2-10-2s
of
class 533A were more than the equal of their work, there was still a
need
for a locomotive for the more lightly-laid routes, in particular the
lines
from Kropčahne to Tstaie and Lamechov. The addition of an extra
driving
axle, combined with a more modern, 3-cylinder compound power unit,
resulted
in this machine, the 634A. It was originally intended to order the
634As from Babcock
&
Wilcox
in Bilbao but unfortunately this firm had completed their last steam
locos in 1961, and so the RSR works in Bevice got the order. The engines acquitted
themselves
very well on the work they were given, regularly hauling loads of 1200
tonnes up the 1 in 85 gradients to Pelašin and Čavoka. By now
standard
features included boxpok wheels, poppet valves and Vanderbilt tender.
At the time of
writing, the whole class is still in service, sharing work with the
Garratts
and 4-10-4s.
The Chinese class QJ
2-10-2, which went into production at Datong Works in 1964, carried a
skyline casing. In order not to be left out, Ketterik had a few 634As
fitted with this device, which, although it serves a purpose on the QJ
(as cladding for the external steam pipe from dome to superheater), is
of no use to an RSR locomotive. The casings had disappeared by 1971.