Steam Turbine Services
TECNORIVA has more of 20 years of experience in the maintenance, service and improving of steam turbines in the range 1 – 60 MW.
TECNORIVA developed the capability to perform the revamping of existing steam turbines to up to date the old control system using modern digital controls.
Tecnoriva is able to support the customer during all the life of the turbines, in order to guarantee the best system efficiency.
With the predictive maintenance approach, Tecnoriva can identify both the critical problems and the residual life of the consumable components to manage the optimal maintenance path in accordance with the customer production needs and business plans.
CONTROL SYSTEM REVAMPING
The proposed control system revamping consists in the change of the existing governor with a new digital (i.e. Woodward 505) and the related actuator necessary to control the regulating valves.
In detail (the description referred to the condensing steam turbine, without controlled extraction) the modification, that can be performed in occasion of a general overhaul of the machine, is below described:
- Dismantling the existing hydraulic-mechanical governor (i.e. Woodward UG40) and the related mechanical and connected links to the control valves servomotor
- Dismantling all the mechanical drive of the governor, like gears, bearings supports
- Eliminate the pinion on the rotor (necessary to drive the old governor) and install a new phonic wheel
- Install on the bearing support the two speed pick up that will give the speed signal to the governor.
- Install a new position actuator (to be defined according to the turbine layout) that receive the signal from the governor and control the position of the regulating valves
- Modify the control oil piping in order to give the necessary oil to the actuator
- Install all the necessary covers on the turbine to close the opening due dismantled parts
- Install the necessary brackets to support the actuator
- Install the new links between the actuator to the control valves servomotor
- Provide the electrical connections between the speed sensors and the governor and the between the actuator and the governor
The advantages of this modification are:
Improving of system reliability of the machine. Due to the elimination of moving parts subject to wear and possible breakage the risk to stop the machine with the relevant costs of repair and loss of production become negligible
Facility to modify the operation parameters, in order to adjust the turbine to operations of the plant
The turbine can be remote controlled by DCS
The quantity of necessary spare is minimum (two speed pick up), with minimum costs
Maintenance required time and costs are practically reduced to zero.
In case of several machines present on the plant the standardization facilitate the operators reducing the managing risks.
The package supplied by TECNORIVA include:
- Feasibility study of the system to define the best solution
- Provide the design and all necessary drawings to manufacture and install all the parts
- The governor
- The actuator
- The speed pick up (2)
- The phonic wheel
- The hard ware to install the pick up
- The necessary cover to close the openings due to the dismantling of the old components
- The modification of the rotor to install the phonic wheel
- The assistance during the install
- The assistance to turbine start up for the complete setting of the governor parameters
Survey of design, construction and tests (FAT) of steam turbine
TECNORIVA is organized with specialized technicians and equipments to give to the Client the best results in the following activities:
- LTSA and assistance
- Survey design and construction
- Coordination of the design and construction activities
In particular, for what concern turbine design and manufacturing survey, TECNORIVA has capability and experience to insure to the Client a complete service, articulated as thereinafter described:
Control of relevant drawings to verify the compliance with contractual technical specification.
Control of the Quality Insurance Plan content
Control of the respect of schedule for what concern the issuing of the contractual and interface drawings.
Provide the necessary expediting actions whenever verified schedule discrepancies
– gland condenser system and ancillaries equipments
– main condenser, if in the scope of the supply
– turbine and generator control system
– generator cubicles – center star, measurements
– oil console
Control of the construction of the Main Items