What causes shaft bowing?

Bowing of shaft occurs when the turbine is shut down faster and shaft cooling time is not proper causing the shaft bend at center to any direction. Bowing of the shaft can make the rotor blades striking the casing of turbine causing crack in the blade due to fatigue loading.

What is sagging and hogging in steam turbine?

In solid mechanics, structural engineering, and shipbuilding, hogging and sagging describe the shape that a beam or similar long object will deform into when loading is applied. Hogging describes a beam that curves upwards in the middle, and sagging describes a beam that curves downwards.

What are the causes of vibration and noise in steam turbine?

The vibration is caused by insufficient clearance between stationary and rotating parts, as well as a shaft located off-center in its bearing. Again, the rubbing causes friction between stationary and rotating parts, localized heating of the rotor metal at the contact point, and shaft bending.

What are the 8 main causes of turbine vibration?

TOP 22 REASON’S BEHIND STEAM TURBINE VIBRATION IN POWER PLANT

• Unbalance of the steam turbine rotor.
• Unbalanced of steam turbine rotor parts.
• Loss parts of steam turbine cylinders.
• Deposited on steam turbine blades.
• Damage of journal bearings.
• Rotor shaft axial shift.
• Differential expansion.

What is Morton effect?

The Morton effect (ME) is a phenomenon of synchronous thermal instability (STI). It is most often reported in turbomachinery applications. This effect has been a latent threat to rotor stability since fluid bearing–supported rotating machinery was first put in use.

What is turbine rub?

A rub is secondary indicator that occurs when there is contact between rotating and non-rotating components. Some of the primary causes that can lead to a rub are: high vibration. tight or incorrect clearance.