How do triple expansion steam engines work?

A triple-expansion engine is a compound engine that expands the steam in three stages, e.g. an engine with three cylinders at three different pressures. A quadruple-expansion engine expands the steam in four stages, and so on.

Why is it called a triple expansion engine?

It is a logical extension of the compound engine (described above) to split the expansion into yet more stages to increase efficiency. The result is the multiple-expansion engine. Such engines use either three or four expansion stages and are known as triple- and quadruple-expansion engines respectively.

How does Walschaerts valve gear work?

When greater power is necessary, e.g. when gaining speed when pulling out of a station and when ascending a gradient, the Walschaerts valve gear enables the engine driver to set the cutoff point near the end of the stroke, so that the full pressure of the boiler is exerted on the piston for almost the entire stroke.

What are the two types of valve gear?

They can be divided into those that drove the standard reciprocating valves (whether piston valves or slide valves), those used with poppet valves, and stationary engine trip gears used with semi-rotary Corliss valves or drop valves.

How do steamship engines work?

The steam engines on steamboats burned coal to heat water in a large boiler to create steam. The steam was pumped into a cylinder, causing a piston to move upward to the top of the cylinder. A valve would then open to release the steam, allowing the piston to fall back to the bottom of the cylinder.

What is a uniflow engine?

: an engine in which the steam or gas enters through admission valves at the ends of the cylinder and escapes through exhaust ports uncovered by the piston as it nears the end of its stroke.

What kind of engine did the Titanic have?

RMS Titanic Two reciprocating steam engines – with a combined output of 30,000 horsepower and each weighing 720 tonnes – and one low-pressure turbine powered the Titanic. They needed the steam produced by 29 boilers, each capable of holding more than 48 tonnes of water.

Do steam engines have gears?

The steam locomotive, as commonly employed, has its pistons directly attached to cranks on the driving wheels; thus, there is no gearing, one revolution of the driving wheels is equivalent to one revolution of the crank and thus two power strokes per piston (steam locomotives are almost universally double-acting.

What is steam lap?

Lap is the amount by which the valve overlaps each port at the middle position of each valve. The first kind is the steam lap, which is the amount by which the valve overlaps the steam port on the live steam side of the piston or slide valve (i.e. the distance the valve needs to move to just begin to uncover the port).

What kind of steam engine is a triple expansion?

Model triple expansion marine steam engine This is a model of a triple expansion marine steam engine. Triple expansion engines were the most popular and efficient steam engines of the late 1800s. They were commonly used in ships until the 1950s.

What kind of steam engine has three cylinders?

Triple expansion engines were the most popular and efficient steam engines of the late 1800s. They were commonly used in ships until the 1950s. These engines have three cylinders and pistons. The steam passes in sequence from the smallest cylinder to the largest, driving each in turn.

What kind of gear does a Stephenson steam engine use?

Standard Stephenson reversing gear is fitted for each cylinder, the only unusual feature being te the eccentric sheaves for the I.P. cylinder are split as they with between two sets of crank webs. Standard big end split brasses are fitted.