GF-ELTI Furnaces for Dynamic Stability Verification are plants used to make sure that the eccentricity of rotors or shafts - measured during a hot test - lies within the tolerance values set by the standards of reference or the contractual clauses defined by the Customer. The test simulates the heat operating conditions of the plants where rotors will be installed.
These furnaces typically consist of:
The furnace modules can be placed one close to each other in several configurations according to the length of the rotor or shaft under test.
Every single furnace module consists of two half-shells: the lower one is fixed whereas the upper one is openable to load and unload the rotors or shafts under test. The lower half-shell is complete with guides and wheels for movement.
The tailstock and the rotating disks are complete with guides and wheels for handling and positioning.
The dynamic stability test consists in heating the piece by starting from the ambient temperature up to the operation temperature with an increase gradient defined at the time of the contract with the Customer. Once achieved, the operation temperature of e.g. abt. 700 °C is kept for min. 3 hours (for max. some days); then, the rotor is cooled down (either naturally or forcedly).
During the whole test, the piece is kept rotating at a speed of 2÷4 turns/minute and at pre-established intervals; any radial deformation of the piece is detected by measuring tracer points; the longitudinal elongation is checked by a position transducer at the same height as the tailstock; when stable, it confirms the heat uniformity of the piece and validates the beginning of the period, in which the test temperature is maintained. All the data measured during the test are stored by the system to produce a complete test report and enable the operator to check whether any deformation of the piece lies within the required tolerance values.
Types of treated products: axial-symmetric products, such as rotors, shafts, etc.
