Marine steam boilers / [by] J. (James Hugh). London: Newnes-Butterworths, 1970. Physical Description. Viii, 516 p.: ill., plans; 23 cm. Marine engineering series. Steam-boilers, Marine. Dewey Number. Sectional diagram of a 'wet back' boiler The general layout is that of a squat horizontal cylinder.

Cochran boiler Parallel tube boilers place all of their fire-tubes in a single parallel group, running from side to side of the boiler shell. Download velamma episode 14 in hindi. The best known of these is the design. Cochran boiler [ ] The Cochran boiler was produced by Cochran & Co. Of, Scotland.

It is widely used in marine practice, either fired directly by coal or oil fuels, or else used for from the exhaust of large diesel engines. Where such a boiler may be heated either by the exhaust gases of the main propulsion plant, or else separately fired when in port (usually by oil rather than coal) it is referred to as a composite boiler. The boiler is a cylindrical vertical water drum with a domed top. This domed shape is strong enough not to require. The is another hemispherical dome, riveted to the base to give a narrow waterspace. The fire-tubes are arranged in a single horizontal group above this, mounted between two flat vertical plates that are inset into the boiler barrel.

The first of these plates forms a shallow and is connected to the firebox by a short diagonal neck. The combustion chamber is of the 'dry back' form and is closed by a steel and firebrick plate, rather than a water jacket. The exhaust from the fire-tubes is into an external and a vertical.

For maintenance access to the tubes, a manhole is provided in the hemispherical dome. A typical Cochran boiler, as illustrated, might be 15 feet (4.6 m) high and 7 feet (2.1 m) in diameter, giving a heating surface of 500 square feet (46 m 2) and a grate area of 24 square feet (2.2 m 2). Working pressure is between 100 and 125 psi. Where composite firing is used, there are several possible arrangements for the heating gases. Most use a double-pass tube arrangement where another dry back combustion chamber routes the gases from one tube bank to return through the other.

Some arrangements use a separate tube bank for the heat recovery exhaust gases or the direct firing gases, others pass the exhaust gases into the top of the (unlit) firebox. A pure heat-recovery boiler may have no firebox at all, other than a shallow domed plate for strength. Clarke Chapman 'wet back' 'Victoria' boiler The Clarke Chapman boiler is similar to the Cochran type, with the difference that the top of the boiler shell is a shallow dome rather than a hemisphere. This dome shape is still sufficiently strong to withstand the pressure, but there is now a sharp corner between the shell and the top plate. This corner requires the support of. Clarke Chapman boilers are made in both 'dry back' (as for the Cochran) and 'wet back' forms.