GNR Class H4

Infobox Locomotive
powertype=Steam
name = GNR Class H4
LNER Class K3

---

caption = 61985 at Annesley MPD on 28 October 1962
designer = Nigel Gresley
builder =
builddate = 1920-1937
totalproduction =
whytetype = 2-6-0
gauge = standard gauge
leadingsize =
driversize = 5' 8"
length =
weight = 72 tons 12 cwt
fueltype = coal
fuelc

waterc

cylindercount = three
cylindersize = 18½" x 26"
firearea =
boilerpressure = 180 psi
tractiveeffort = 30,030 lbf
railroadclass= 5P6F|

The Great Northern Railway Class H4 (classified K3 by the LNER) was a class of 2-6-0 steam locomotive designed for mixed-traffic work.

The type was a more powerful development of the earlier H3 (LNER K2) class, and was notable at the time as the 6 foot diameter boilers were the largest fitted to any British locomotive to that date. After formation of the London and North Eastern Railway the type became known as class K3, and was adopted as an LNER standard design.

Construction

The first ten locomotives were built at the GNR's Doncaster Works in 1920, to the design of Nigel Gresley. Six further batches were built at Doncaster and Darlington Works, Armstrong Whitworth, Robert Stephenson and Company and the North British Locomotive Company. The last examples were delivered in 1937, with a total of 193 locomotives having been built.

Use

They were excellent mixed traffic locomotives, although their large size restricted their route availability. In their latter years they were primarily employed on vacuum fitted freight traffic.

Class K5

In 1945, Edward Thompson rebuilt K3 No. 206 into a two-cylinder engine forming the LNER Class K5. No more were so treated, although some later received K5 type boilers.

Numbering

The original ten locomotives were numbered 1000-1009 by the GNR, and became LNER 4000-4009. Those built for the LNER were numbered haphazardly, filling in gaps in the LNER's numbering scheme. In the LNER's 1946 renumbering programme the K3s and K5 were renumbered 1800-1992, and they later became British Railways 61800-61992.

Withdrawal

All were withdrawn between 1959 and 1962 (the K5 going in 1960). None survived into preservation.

References

*
* Ian Allan ABC of British Railways Locomotives, 1948 edition, part 4, page 17

External links

* [http://www.lner.info/locos/K/k3k5.shtml LNER encyclopedia]
* [http://www.lner.info/locos/K/k3k5.shtml Railuk database]