Transverse boiler
Encyclopedia
A transverse boiler is a boiler used to generate steam to power a vehicle. Unlike other boilers, its external drum is mounted transversely across the vehicle.
The obvious advantage of the transverse boiler is that it is short lengthways, compared to a locomotive boiler. Where space is short, such as with railmotors, this can give more usable space inside. A less obvious, but more significant advantage for road vehicles, is that the water level of the boiler is less sensitive to the road gradient. When descending steep hills, there is less risk of the firebox crown being exposed above the water level and dangerously overheating.
Transverse boilers are broadly similar to locomotive boilers in construction. They have an internal firebox with multiple small fire-tubes.
for its distinctive steam wagons. This boiler, the company's eponymous patent, was unique in being both transverse and double-ended. This patent was applied for in 1900 and the boiler continued in production until 1937. It was designed to provide a compact boiler with ample heating surface and pre-dated other effective designs of vertical boiler, such as the Sentinel
.
The boiler consists of one long horizontal transverse drum, with a central locomotive-style firebox mounted in an extension beneath. The first boilers had a square firebox, but this was later changed to a circular section. Firing with coke
is carried out through a firedoor in the side of the shell, to the rear of the boiler when installed. Fire-tubes lead to a shallow smokebox at each side, from which return tubes pass to a central chamber beneath the chimney. The chimney is wrapped with an extension of the boiler shell, acting as a steam collecting dome. There are 32 tubes in total from the firebox, of 1¾ inch diameter, and 28 more to the chimney chamber. Longitudinal stays support the flat tubeplates at each side. An unusual feature is that rather than the usual single blastpipe
beneath the chimney, there are 14 of them on each side inside each smokebox, pointing into the return tubes. Exhaust steam from the engine reaches these blastpipes through a prominent copper pipe on the outside of each smokebox door.
The working pressure was 200 lb. sq. in., comparable to the more advanced locomotives of the period.
An advantageous feature of the boiler was that the fire-tubes were entirely submerged. Competing vertical boilers of the period had semi-submerged tubes with their upper ends in the steam space above the water level, leading to erosion and rapid tube wear around the level.
s used transverse boilers, instead of the more common vertical boilers, or short locomotive boilers. These were chosen to provide a compact boiler, but with easier servicing than for a vertical boiler.
The obvious advantage of the transverse boiler is that it is short lengthways, compared to a locomotive boiler. Where space is short, such as with railmotors, this can give more usable space inside. A less obvious, but more significant advantage for road vehicles, is that the water level of the boiler is less sensitive to the road gradient. When descending steep hills, there is less risk of the firebox crown being exposed above the water level and dangerously overheating.
Transverse boilers are broadly similar to locomotive boilers in construction. They have an internal firebox with multiple small fire-tubes.
Yorkshire Patent steam wagons
The best known transverse boiler was that used by the Yorkshire Patent Steam Wagon Co.Yorkshire Patent Steam Wagon Co.
The Yorkshire Patent Steam Wagon Co. was a steam wagon manufacturer in Leeds, England. They produced their first wagon in 1901. Their designs had a novel double-ended transverse boiler. In 1911 the company's name was changed to Yorkshire Commercial Motor Co., but reverted to Yorkshire Patent Steam...
for its distinctive steam wagons. This boiler, the company's eponymous patent, was unique in being both transverse and double-ended. This patent was applied for in 1900 and the boiler continued in production until 1937. It was designed to provide a compact boiler with ample heating surface and pre-dated other effective designs of vertical boiler, such as the Sentinel
Sentinel boiler
The Sentinel boiler was a design of vertical boiler, fitted to the numerous steam waggons built by the Sentinel Waggon Works.The boiler was carefully designed for use in a steam wagon: it was compact, easy to handle whilst driving, and its maintenance features recognised the problems of poor...
.
The boiler consists of one long horizontal transverse drum, with a central locomotive-style firebox mounted in an extension beneath. The first boilers had a square firebox, but this was later changed to a circular section. Firing with coke
Coke (fuel)
Coke is the solid carbonaceous material derived from destructive distillation of low-ash, low-sulfur bituminous coal. Cokes from coal are grey, hard, and porous. While coke can be formed naturally, the commonly used form is man-made.- History :...
is carried out through a firedoor in the side of the shell, to the rear of the boiler when installed. Fire-tubes lead to a shallow smokebox at each side, from which return tubes pass to a central chamber beneath the chimney. The chimney is wrapped with an extension of the boiler shell, acting as a steam collecting dome. There are 32 tubes in total from the firebox, of 1¾ inch diameter, and 28 more to the chimney chamber. Longitudinal stays support the flat tubeplates at each side. An unusual feature is that rather than the usual single blastpipe
Blastpipe
The blastpipe is part of the exhaust system of a steam locomotive that discharges exhaust steam from the cylinders into the smokebox beneath the chimney in order to increase the draught through the fire.- History :...
beneath the chimney, there are 14 of them on each side inside each smokebox, pointing into the return tubes. Exhaust steam from the engine reaches these blastpipes through a prominent copper pipe on the outside of each smokebox door.
The working pressure was 200 lb. sq. in., comparable to the more advanced locomotives of the period.
An advantageous feature of the boiler was that the fire-tubes were entirely submerged. Competing vertical boilers of the period had semi-submerged tubes with their upper ends in the steam space above the water level, leading to erosion and rapid tube wear around the level.
Railmotors
Some rare steam railmotorRailmotor
Railmotor is a term which was used by several British railway companies for a steam railcar.-Overview:William Bridges Adams started building railmotors as early as 1848, but only in small numbers...
s used transverse boilers, instead of the more common vertical boilers, or short locomotive boilers. These were chosen to provide a compact boiler, but with easier servicing than for a vertical boiler.