What are the 2 types of valve gear?
What are the 2 types of valve gear?
Constant lead gear (Walschaerts-type gear) One component of the motion comes from a crank or eccentric. The other component comes from a separate source, usually the crosshead. Walschaerts or Heusinger valve gear – most common valve gear on later locomotives, normally externally mounted.
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.
Which valve is in locomotive?
In Electric Locomotives pneumatic brake system is employed for braking the locomotive as well as trailing stock. Pneumatic valves play very important role in braking system. CAMTECH has prepared this training package to impart basic knowledge of these valves, their maintenance, tests etc to the field personnel.
How does caprotti valve gear work?
The Caprotti valve gear is a type of steam engine valve gear invented in the early 1920s by Italian architect and engineer Arturo Caprotti. It uses camshafts and poppet valves rather than the piston valves used in other valve gear.
How does Baker valve gear work?
Operation. The Baker valve gear replaces the expansion link of the Walschaerts gear with an assembly of levers and links which produces the same effect of allowing continuous variation valve travel.
How does Joy valve gear work?
JOY’S VALVE GEAR, invented by the late David Joy in 1879, dispenses with eccentrics, the valve being operated by a dire-block moving in a curved guide. The die-block is connected at its upper end to the valve spindle by a radius rod and by a system of links to the connecting rod.
Which type of safety valve is used in locomotive boiler?
The first three type of safety valves are usually employed with stationary boiler but the fourth type is mainly used for locomotive and marine boilers.