NSB Class 21

The Norwegian State Railways 21 (21a, 21b, 21c, 21d & 21e) Class are 2-6-0 tender steam locomotives.
==History==
The 21 (21a, 21b, 21c, 21d and 21e) class are a class of forty-two tender 2-6-0 locomotives. The class were first built in 1904 by the Hamar Iron Foundry then later by the Thunes Mechanical Workshop and last by NOHAB with the last being built in 1919. The 21 class was the most successful and numerous steam locomotive to be used by the Norwegian State Railways with five subclasses being produced. They were designed for small to medium sized goods and passenger trains essentially being general purpose mixed traffic locomotives.https://forsk.njk.no/mdb/mdb.php?hid=31&aut=&visallebilder=1 (Translated by Google)https://njk.no/kroderbanen-rullende-materiell/lokomotiver (Translated by Google)https://jernbane.net/bo/subpage.php?s=3&t=113 (Translated by Google)http://members.ozemail.com.au/~telica/Norway_Kroderbanen.htmlhttps://www.ebe-data.com/Hobby/Jernbanebilder/Norge/Lok/Damp.htm#Normalspor (Translated by Google)https://www.steamlocomotive.info/country.cfm?which=norwayhttps://www.brc-stockbook.co.uk/haakon.htmhttps://bressingham.co.uk/explore/locomotives.aspx
===21a===
The 21a subclass were the successors to the 15c class but has a smaller wheelbase of up to 3 metres less then the 15c as well as a higher placement of the boiler among other modifications. These changes were made due to the tight curves in Bergen harbour and the overall Voss line. There were a total of 20 21a subclass locomotives built.
===21b===
This subclass were identical to the 21a class but were superheated this made the locomotives stronger and more fuel efficient. They were the first superheated locomotives on the Norwegian State Railways with a total of 14 locomotives constructed of the class.
===21c===
From the first world war a new type of technology called feed water preheaters had become popular and thus they were fitted to a total of eight locomotives constructed to this class which became a new designation of the 21 class due to the class gaining up to 2 tons with the preheaters fitted. The feed water preheaters reduced coal consumption but was quite complicated and difficult to utilize and also required a lot of maintenance. This rendered the preheaters uneconomic despite their fuel reducing capabilities. All of the class had the preheaters removed but retained their 21c designation.
===21d===
This class was a total of six locomotives converted from 21a that retained their compound machinery but were superheated. These conversions happened from 1923 to 1925 with all 21d locomotives being converted to 21e.
===21e===
Locomotives of 21d fitted with twin machinery and external influx changing the appearance of their cylinder arrangement slightly the conversion also improved the locomotives performance. Later on 3 21a class locomotives were also converted to 21e creating a total of 9 locomotives in the 21e class.
==Preservation==
Five of the 21 class have been preserved being No.252 and 225 from the 21b class, and No.376 and 377 from the 21c class, and 207 from the 21e class. Both 252 and 225 are stored awaiting overhauls while No.376 and 377 are both in the United Kingdom also awaiting overhauls with No.377 on display. No.207 is in storage in a warehouse owned by the Norwegian Railway Club awaiting restoration to operation.
==List of Locomotives==
Class list of locomotives of the 21 (21a, 21b, 21c, 21d and 21e) class.
Image:	No. 	Name: 	Built: 	Builder: 	Builder's No.	Status:
146 	 	 	 	 	 	
1909 	Hamar Iron Foundry 	38 	Scrapped 	 	 	
149 	 	 	 	 	 	
1910 	Thunes Mechanical Workshops	43 	Scrapped 	 	 	
150 	 	 	 	 	 	
1910 	Thunes Mechanical Workshops	44 	Scrapped 	 	 	
 	174 	- 	1904 	Thunes Mechanical Workshops	9 	Scrapped
175 	- 	1904 	Thunes Mechanical Workshops	10 	Scrapped 	
 	176 	- 	1904 	Thunes Mechanical Workshops	11 	Scrapped
177 	- 	1904 	Thunes Mechanical Workshops	12 	Scrapped 	
178 	- 	1904 	Thunes Mechanical Workshops	13 	Scrapped 	
179 	- 	1906 	Hamar Iron Foundry 	15 	Scrapped 	
180 	- 	1906 	Hamar Iron Foundry 	16 	Scrapped 	
 	181 	- 	1906 	Hamar Iron Foundry 	17 	Scrapped
182 	- 	1906 	Thunes Mechanical Workshop 	21 	Scrapped 	
 	183 	- 	1906 	Thunes Mechanical Workshop 	22 	Scrapped
201 	- 	1909 	Thunes Mechanical Workshop 	35 	Scrapped 	
202 	- 	1909 	Thunes Mechanical Workshop 	36 	Scrapped 	
203 	- 	1909 	Thunes Mechanical Workshop 	37 	Scrapped 	
 	204 	- 	1909 	Thunes Mechanical Workshop 	38 	Scrapped
205 	- 	1909 	Thunes Mechanical Workshop 	39 	Scrapped 	
206 	- 	1909 	Thunes Mechanical Workshop 	40 	Scrapped 	
 	207 	- 	1909 	Hamar Iron Foundry 	46 	Preserved: Stored
208 	- 	1909 	Hamar Iron Foundry 	36 	Scrapped 	
209 	- 	1909 	Hamar Iron Foundry 	37 	Scrapped 	
224 	- 	1911 	Thunes Mechanical Workshop 	51 	Scrapped 	
 	225 	- 	1911 	Thunes Mechanical Workshop 	52 	Scrapped
237 	- 	1912 	Hamar Iron Foundry 	75 	Scrapped 	
251 	- 	1912 	Hamar Iron Foundry 	81 	Scrapped 	
 	252 	- 	1912 	Hamar Iron Foundry 	82 	Preserved: Stored
253 	- 	1912 	Hamar Iron Foundry 	83 	Scrapped 	
294 	- 	1916 	Hamar Iron Foundry 	109 	Scrapped 	
295 	- 	1916 	Hamar Iron Foundry 	110 	Scrapped 	
312 	 	1919 	Hamar Iron Foundry 	126 	Scrapped 	
313 	 	1919 	Hamar Iron Foundry 	127 	Scrapped 	
314 	 	1919 	Hamar Iron Foundry 	128 	Scrapped 	
315 	 	1919 	Hamar Iron Foundry 	129 	Scrapped 	
370 	- 	1919 	NOHAB 	1157 	Scrapped 	
371 	- 	1919 	NOHAB 	1158 	Scrapped 	
372 	- 	1919 	NOHAB 	1159 	Scrapped 	
373 	- 	1919 	NOHAB 	1160 	Scrapped 	
374 	- 	1919 	NOHAB 	1161 	Scrapped 	
375 	- 	1919 	NOHAB 	1162 	Scrapped 	
 	376 	Norwegian 	1919 	NOHAB 	1163 	Preserved: Under Overhaul
 	377 	King Haakon VII	1919 	NOHAB 	1164 	Preserved: Display
==Trivia==
*
*It is the most well known NSR class.
==Bibliography==
Category:Locomotives
Category:Steam locomotives
Category:Tender locomotives
Category:2-6-0 locomotives
Category:2-6-0 steam locomotives
Category:Preserved locomotives
Category:Built in 1909
Category:Norway
Category:4 foot 8 1⁄2 inch gauge
Category:Standard gauge locomotives
Category:Six-coupled locomotives
Category:Hamar Locomotives
Category:Norwegian State Railways
Category:NSR Main Network
Category:NSR Krøder Line
Category:Thunes Locomotives
Category:NOHAB Locomotives
Category:Built in 1904
Category:Built in 1906
Category:Built in 1910
Category:Built in 1911
Category:Built in 1912
Category:Built in 1916
Category:Built in 1919
Category:NSR Old Voss Line