Gas Turbine Thrust Ring Adjustment for Rotor Axial Movement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Gas turbine electric power plants face issues with excessive axial movements of the rotor due to thermal expansion and centrifugal forces, leading to inefficient operation from either excessive contact or blow-by between rotating and fixed parts, which existing bearing assemblies fail to adequately compensate.
Innovation Solution
A maintenance method involving a hydraulic piston system with adjustable thrust rings to control axial movements by modifying the stroke of the rotor, using interchangeable thrust rings to adjust the distance between rotor and stator parts based on specific operational conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If bearing assemblies are used to compensate axial movements, then rotor axial position control is improved, but the compensation capability is insufficient under extreme thermal and centrifugal conditions
Solution Approach 1:
The bearing assembly is designed with interchangeable thrust rings of different thicknesses, allowing the axial compensation capability to be dynamically adjusted based on operating conditions. The hydraulic piston system provides active control, making the bearing assembly adaptable to varying thermal expansion and centrifugal force conditions throughout the gas turbine's operational lifecycle.
Solution Approach 2:
The invention changes the physical parameter of thrust ring thickness to adjust the axial compensation range. By selecting thrust rings with different thicknesses (e.g., first thickness for normal operation, second thickness for high-temperature conditions), the system adapts to different operational parameters and maintains reliable axial position control across the full operating envelope.
2Productivity
If rotor axial movement compensation is increased, then efficiency is improved by preventing blow-by, but the risk of contact between rotor and stator parts increases
Solution Approach 1:
The hydraulic piston system enables dynamic adjustment of the rotor axial position, allowing the system to optimize the gap between rotor and stator parts in real-time. This dynamic control prevents excessive blow-by (improving efficiency) while simultaneously avoiding mechanical contact (reducing harmful factors), adapting to changing operational conditions.
Solution Approach 2:
By changing the thrust ring thickness parameter, the system adjusts the baseline axial position of the rotor. Thinner thrust rings allow greater axial movement range to prevent blow-by, while thicker thrust rings provide a safety margin to prevent contact. The hydraulic system fine-tunes the position within this range to optimize efficiency without risking contact.
3Stability of the object's composition
If bearing assembly design is modified to improve axial compensation, then rotor position stability is improved, but maintenance complexity and disassembly requirements increase
Solution Approach 1:
The bearing assembly is segmented into modular components: the support body, hydraulic piston system, and interchangeable thrust rings. This segmentation allows the thrust rings to be independently replaced without disassembling the entire bearing assembly or removing the rotor, maintaining rotor position stability while significantly improving ease of repair.
Solution Approach 2:
The thrust rings are designed as extractable components that can be removed from the bearing assembly without disassembling the support body or rotor. This extraction capability allows maintenance personnel to replace worn or inappropriate thrust rings with new ones of different thicknesses, maintaining stable rotor positioning while enabling simple maintenance operations.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method effectively minimizes axial movements, reducing maintenance time and costs by allowing on-site adjustments without disassembling the rotor or support body, thus optimizing plant efficiency and safety.
Implementation Method 1
a bearing assembly, which comprises a hydraulic piston configured to axially move the rotor
Implementation Method 2
The rotor in gas turbine electric power plants of this type is often subjected to axial movements, mainly due to phenomena of thermal expansion
Implementation Method 3
The rotor in gas turbine electric power plants of this type is often subjected to axial movements, mainly due to phenomena of thermal expansion and to the centrifugal action to which the rotor is subjected during the operation of the plant
Data Source
Figure 1
Figure 2
Figure 2A
AI summary
A maintenance method for a gas turbine electric power plant (1) involves replacing the thrust ring (29, 38; 30) of a bearing assembly (16) arranged about a shaft (8) of the plant (1) with a spare thrust ring having a different thickness (NR), intended as the axial length between a thrust face (51) and at least one abutting face (53) of the wall (50) of the thrust ring (29, 38; 30).