South African Class 1B 4-8-2

Specifications
Specifications
Configuration:;
• Whyte	4-8-2 (Mountain)
• UIC	2'D1'n2
Driver	2nd coupled axle
Gauge	3 ft 6 in (1,067 mm) Cape gauge
Leading dia.	28+1⁄2 in (724 mm)
Coupled dia.	45+1⁄2 in (1,156 mm)
Trailing dia.	28+1⁄2 in (724 mm)
Tender wheels	30 in (762 mm)
Wheelbase	49 ft 5⁄8 in (14,951 mm)
• Engine	27 ft 6 in (8,382 mm)
• Leading	6 ft (1,829 mm)
• Coupled	12 ft 9 in (3,886 mm)
• Tender	15 ft 6 in (4,724 mm)
• Tender bogie	4 ft 6 in (1,372 mm)
Length:;
• Over couplers	56 ft 4+7⁄8 in (17,193 mm)
Height	12 ft 6 in (3,810 mm)
Frame type	Plate
Axle load	14 LT 17 cwt (15,090 kg)
• Leading	12 LT 2 cwt (12,290 kg)
• 1st coupled	14 LT 2 cwt (14,330 kg)
• 2nd coupled	14 LT 17 cwt (15,090 kg)
• 3rd coupled	14 LT (14,220 kg)
• 4th coupled	13 LT (13,210 kg)
• Trailing	2 LT 10 cwt (2,540 kg)
• Tender bogie	Bogie 1: 18 LT 18 cwt (19,200 kg); Bogie 2: 19 LT 1 cwt (19,360 kg)
• Tender axle	9 LT 10 cwt 2 qtr (9,678 kg)
Adhesive weight	55 LT 19 cwt (56,850 kg)
Loco weight	70 LT 11 cwt (71,680 kg)
Tender weight	37 LT 19 cwt (38,560 kg)
Total weight	108 LT 10 cwt (110,200 kg)
Tender type	SH (2-axle bogies); SH, SK permitted
Fuel type	Coal
Fuel capacity	6 LT (6.1 t)
Water cap.	3,225 imp gal (14,700 L)
Firebox:
• Type	Belpaire & combustion chamber
• Grate area	34 sq ft (3.2 m2)
Boiler:;
• Pitch	7 ft 3 in (2,210 mm)
• Diameter	5 ft 4+3⁄4 in (1,645 mm)
• Tube plates	12 ft 1 in (3,683 mm)
• Small tubes	325: 2 in (51 mm)
Boiler pressure	190 psi (1,310 kPa)
Safety valve	Ramsbottom
Heating surface:
• Firebox	128.63 sq ft (11.950 m2)
• Tubes	2,094.17 sq ft (194.555 m2)
• Total surface	2,222.8 sq ft (206.50 m2)
Cylinders	Two
Cylinder size	20+1⁄2 in (521 mm) bore; 24 in (610 mm) stroke
Valve gear	Walschaerts
Valve type	Murdoch's D slide
Couplers	Johnston link-and-pin; AAR knuckle (1930s)

Type and origin
Type and origin
Power type	Steam
Designer	Natal Government Railways; (D.A. Hendrie)
Builder	North British Locomotive Company; Natal Government Railways
Serial number	16414-16419
Model	NGR Class B
Build date	1906
Total produced	6
Rebuilder	South African Railways
Rebuild date	1926-1928
Number rebuilt	6 to SAR Class 1 4-8-0 (Mastodon)

NGR Class B 4-8-2 1906
South African Class 1B 4-8-2
NGR Class B 4-8-2 1906; South African Class 1B 4-8-2
	SAR Class 1B no. 1445, ex NGR Class B no. 324
Power type
Type and origin
Power type	Steam
Designer	Natal Government Railways; (D.A. Hendrie)
Builder	North British Locomotive Company; Natal Government Railways
Serial number	16414-16419
Model	NGR Class B
Build date	1906
Total produced	6
Rebuilder	South African Railways
Rebuild date	1926-1928
Number rebuilt	6 to SAR Class 1 4-8-0 (Mastodon)
Configuration:;
Specifications
Configuration:;
• Whyte	4-8-2 (Mountain)
• UIC	2'D1'n2
Driver	2nd coupled axle
Gauge	3 ft 6 in (1,067 mm) Cape gauge
Leading dia.	28+1⁄2 in (724 mm)
Coupled dia.	45+1⁄2 in (1,156 mm)
Trailing dia.	28+1⁄2 in (724 mm)
Tender wheels	30 in (762 mm)
Wheelbase	49 ft 5⁄8 in (14,951 mm)
• Engine	27 ft 6 in (8,382 mm)
• Leading	6 ft (1,829 mm)
• Coupled	12 ft 9 in (3,886 mm)
• Tender	15 ft 6 in (4,724 mm)
• Tender bogie	4 ft 6 in (1,372 mm)
Length:;
• Over couplers	56 ft 4+7⁄8 in (17,193 mm)
Height	12 ft 6 in (3,810 mm)
Frame type	Plate
Axle load	14 LT 17 cwt (15,090 kg)
• Leading	12 LT 2 cwt (12,290 kg)
• 1st coupled	14 LT 2 cwt (14,330 kg)
• 2nd coupled	14 LT 17 cwt (15,090 kg)
• 3rd coupled	14 LT (14,220 kg)
• 4th coupled	13 LT (13,210 kg)
• Trailing	2 LT 10 cwt (2,540 kg)
• Tender bogie	Bogie 1: 18 LT 18 cwt (19,200 kg); Bogie 2: 19 LT 1 cwt (19,360 kg)
• Tender axle	9 LT 10 cwt 2 qtr (9,678 kg)
Adhesive weight	55 LT 19 cwt (56,850 kg)
Loco weight	70 LT 11 cwt (71,680 kg)
Tender weight	37 LT 19 cwt (38,560 kg)
Total weight	108 LT 10 cwt (110,200 kg)
Tender type	SH (2-axle bogies); SH, SK permitted
Fuel type	Coal
Fuel capacity	6 LT (6.1 t)
Water cap.	3,225 imp gal (14,700 L)
Firebox:
• Type	Belpaire & combustion chamber
• Grate area	34 sq ft (3.2 m2)
Boiler:;
• Pitch	7 ft 3 in (2,210 mm)
• Diameter	5 ft 4+3⁄4 in (1,645 mm)
• Tube plates	12 ft 1 in (3,683 mm)
• Small tubes	325: 2 in (51 mm)
Boiler pressure	190 psi (1,310 kPa)
Safety valve	Ramsbottom
Heating surface:
• Firebox	128.63 sq ft (11.950 m2)
• Tubes	2,094.17 sq ft (194.555 m2)
• Total surface	2,222.8 sq ft (206.50 m2)
Cylinders	Two
Cylinder size	20+1⁄2 in (521 mm) bore; 24 in (610 mm) stroke
Valve gear	Walschaerts
Valve type	Murdoch's D slide
Couplers	Johnston link-and-pin; AAR knuckle (1930s)
Tractive effort
Performance figures
Tractive effort	31,600 lbf (141 kN) @ 75%
Operators
Career
Operators	Natal Government Railways; South African Railways
Class	NGR Altered Class B; SAR Class 1B
Number in class	6
Numbers	NGR 319-324; SAR 1440-1445
Delivered	1906
First run	1906
Withdrawn	1935-1975
	The leading coupled axle had flangeless wheels

The South African Railways Class 1B 4-8-2 of 1904 was a steam locomotive from the pre-Union era in the Colony of Natal.

In 1904, the Natal Government Railways placed fifty Class B locomotives with a 4-8-0 Mastodon wheel arrangement in service. Of these, six were modified in 1906 to Altered Class B locomotives, the first tender engines in the world with a 4-8-2 Mountain wheel arrangement. In 1912, when these six engines were assimilated into the South African Railways, they were renumbered and designated Class 1B.