The Steam Boat Association of Great Britain
SBA Services Limited
Boiler Design Library

All designs that need welding must be made by Certified Welders

SBA Services' Boiler Design Library CD is now available from Julian Garrett. Price £5.00.

The CD contains detailed information and a General Arrangement diagram of all of the designs in the library. The full construction drawings are available for each boiler at a cost of £50 per design.

The designs available are:

1. VFT-100
   Diameter 15 ins (38cm) Height 27.4 ins (69.4cm). Evaporative Surface 13 sq ft (1.2 sq m). Installed in boats "Polly", "Momad", "Melissa"
2. VFT-101
   Diameter 18 ins (45.7cm) Height 24 ins (61cm). Evaporative surface 11.44 sq ft (1.06 sq m)
3. VFT-102
   Diameter 20 ins (50.8 cm) Height 26 ins (66cms). Evaporative surface 17.6 sq ft (1.64 sq m). Installed in "Graculus'
4. VFT-103
   Diameter 22 ins (56 cm) Height 29.5 ins (75 cms). Evaporative surface 24.1 sq ft (2.24 sq m). Installed in "SuiIven", "Nokomis", "Araminta", "Naiad" and many others.
   All evaporative surfaces of the above boilers are measured at normal working level.
   Natural draught evaporation 5lbs/hr per sq ft. Forced draught evaporation10lb/hr per sq ft

1. LOCO-1
   Firebox Ht 31 ins (78.7 cms) width 25.6 Ins (65cm) length 22.5 ins (56 cms)
   Barrel diameter 22.5 ins (57.1 cm) length 24 ins (61 cms). Output 880 lbslhr 400kg/hr maximum. Installed in "Pendlebury" and "Tarka"
2. LOCO-2
   Firebox Ht 22 ins (56 cms) Width 20 ins (51 cms) length 19 ins (48 cms)
   Barrel diameter 16 ins (37 cm) length 18 ins (46 cms). Output 300 Ibslhr 136 kg/hr
   Installed in "Arlette", "Annabelle" and "Hero".

1. WTB-1
   Two drum water tube. Drums Diameter 6.6 ins (16.8 cm) x length 20 ins (50 cms)
   Height in casing 26 ins (66 cms)width 20 ins (50 cms) depth 15.5 ins (39 cms)
   Output not known but suit a small engine. Installed in 'Silkie" and "Lightning".
2. WTB-2
   Vertical water tube. Central drum Diameter 10.75 ins (27.3 cms) length 21 ins (53.3 cms). 20 copper coils 4.75 ins (12cm) diameter. Output not known, suitable for a Stuart 6A. Installed in "Bramble" and "Lady Barbara".
3. WTB-3
   Three drum water tube (two sizes of identical design). Both these boilers are of welded construction, but designs are also available as weldless boilers.
   WTB-3a Size one
   Steam Drum Diameter 8ins (20.3 cms) length 30 Ins (76 cms). Mud drums "D" section 4ins (10.1 cms). Heating Surface 60 sq ft (5.52 sq in). Grate Area 3.12 sq ft (0.29 sq m)
   Designed working pressure 225psig (15.52 bar)
   WTB-3a Size two
   Steam Drum Diameter 10 ins (25.4 cms) Length 36 ins (91.4 cms). Mud drums "D" section 5 ins (12.7 cms) length 36 ins (91.4 cms). Heating surface 72.5 sq ft (6.75 sq m)
   Grate Area 3.9 sq ft (0.36 sq m). Designed working pressure 225psig (15.52 bar)
   WTB-3b Weld-less size one
   Steam drum diameter 6ins (15.2 cms) Length 23 ins ins (58 cms). Mud drums diameter 4 ins (10.2 cms) Length 23 ins ins (58 cms). Heating surface 32 sq ft (2.97 sq mtrs)
   Grate area 2.6 sq ft (0.24 sq mtrs). Working pressure 250 psig (17.24 bar)
   WTB-3b Weld-less Size two
   Steam drum diameter 8ins (20 cms), Length 28.5ins (72 cms). Mud drums diameter 4 ins (10.2 cms), Length 28.25 ins (72 cms). Heating surface 63.7 sq ft (5.9 sq mtrs)
   Grate area 3.9 sq ft 0.36 sq mtrs. Working pressure 250 psig (17.24 bar)
4. WTB-4
   Scott Babcock Boiler. Steam drum diameter 6 ins (15.24 cm). Length 11.5 ins (29 cms)
   Tube plates 15 ins x 8 ins (38 cms x 20.3) all steel. Tubes 51 of 0.75 ins (1.9 cms) OD, 16 SWG copper (steel tubes may be used). Grate area 0.368 sq ft (0.034 sq m). Heating surface 12.4 sq ft (0.34sq m). Steam output 74.4 lbs per hour. This boiler can be built in a larger size with 18 ins (45.7 cms) steam drum giving:- Heating surface 14.9 sq ft (1.384 sq m). Steam output 89.4 lbs per hour. Installed in "Marlin" and other boats.
5. WTB-5
   Blackstaff boiler - three drum water tube. This boiler can be built in tow sizes with 6 coils or 10 coils per side. Steam drum diameter 6 ins (15 cms). length 12.5 ins (32 cms) or 17.5 ins (45 cms) steel. Mud drums 2.5 ins (6.5 cms), length 13 ins (33 cms) or 17 ins (43 cms) steel. Copper coils ½ ins 18 SWG, six or ten off. Heatings surface: small 15.5 sq ft (0.51 sqm) Large 25 sq ft (2.3 sq m). Steam output :- Natural draught evaporation 5 lbs/hr per sq ft. Forced draft evaporation 10 lbs/hr per sq ft

1. HFT-1
   Cochrane type. 18 ins (45.7 cm) diameter, 24 ins (610 cm) high. 44 tubes 1.25 in (3.175 cm). Evaporative surface 19 sq ft (1.76 sq m). Working pressure 240 psi (16.3 bar). Natural draught evaporation 5 lbs/hr per sq ft. Forced draught evaporation 10 lb/hr per sq ft.

Other Certified Boiler Designs exist and are acceptable to the SBA

Valid for 2009.