To make the turbine work more efficiently is accomplished through a number of respective stages. These fundamental stages are synchronized on the basis of the source of energy, and together it is known as impulse or reaction turbines. Steam turbines usually use a blend of both the impulse designs and combination of reactions. But on the whole the turbines use the both, but in rare cases, some use either one of them. Respectively, high pressure turbines with impulse type and lower with the reaction type.

IMPULSE TURBINE

An impulse turbine another version of turbine with nozzles fixed to it, which maintains the flow of steam to the higher speed jets. These jets are molded in such a way with a desirable kinetic energy in which the rotor blades which are shaped as buckets, which help to change the direction of steam. Whenever the steam velocity increases the ratio of pressure decreases at the fixed blades.

When the steam flows through the nozzle, the pressure seems to be minimizing from internal pressure to external pressure. Steam is derived out through the nozzle with a high pressure with a huge velocity. During this time, blades on a whole acquire a maximum velocity of the steam. A large amount of energy gets lose during this period, and this energy is known by the name, ‘carry over velocity’ or ‘leaving loss’.

REACTION TURBINES

In the case of reaction turbines, the rotor blades are designed in such a way as to form convergent nozzles. This type of turbines helps to produce reaction force when the steam is produced through the nozzle formed by the rotor. Here steam is powered to the direction of rotor by the fixed vanes of the stator. The steam produced during this time makes stator in the form of a jet that the entire surface. The direction of steam varies according to the increasing speed of the blade. Once in a while the pressure seems to decrease among the stator and rotor. Even the pressure is decreased during the process, it does not affect the steam velocity, but there is a decrease both in pressure and temperature. The variation in speed and velocity does not affect the one who drives the turbine.

OPERATION AND MAINTENANCE

Whenever the turbine is undergone for a warm up for its use, the main steam superheated is allowed to pass through a bypass passage which helps to heat up the lines of the system along with the steam turbine. In order to prevent the uneven expansion of heat by the slow rotation of turbine during the time when there is no steam in the turbine. For this a turning gear is fixed. When the turbine initially is rotated by the turning gear, it helps to maintain a straight plane within a fixed time limit. After that, the turning gear is detached and the steam is forwarded to the turbine, initially to the ahead blades which makes the turbine to rotate from 10 to 15 RPM in order to warm up the turbine slowly.

A MODERN STEAM TURBINE GENERATOR INSTALLATION

Turbines are widely used because of its rare occurring problems and there is a minimum chance to have maintenance also. Rarely when there is an imbalance occurs in the case of rotor it can lead to the vibration of rotor which in rare cases lead the blade punching straight .It is necessary to notice that there is a minimum amount of water in the turbine and with a dry steam produced during the work of turbine. If the water content is high in the turbine there is a rare chance to produce erosion among the blades. This can even lead turbine to its terrible failure .Moreover when the water enters the turbine it results in the formation of thrust in the turbine shaft. In order to prevent the destruction of turbines, make sure the usage of high quality steam, then preventing the entrance of extra moisture inside the turbine passages are there installed within the passage of piping leading to the turbine.

ACQUIP, INC provides internal steam turbine alignment and internal gas turbine alignment for all of equipment needs in the Oil and Gas, Petrochemical, Marine, and Power Generation Industries

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