Finite Element Analysis of Highbank Rotor Spider
Client : Trustpower Limited
Location : New Zealand
Year : 2021
Cracks have been found in the rotor spider of the Highbank Power Station. The rotor spider is made of cast steel. The Highbank unit is a 29 MW, vertical hydro turbine designed in the late 1930’s but commissioned in 1946.
LDV was contacted by Trustpower to:
- Verify if the cracked Highbank rotor spider is safe to withstand an accidental runaway event;
- Provide their technical opinion on other ways to get indications on the crack origin;
- Investigate the possibility of improving the structural integrity of the rotor spider.
LDV’s investigation was completed by a thorough investigation process performed by Trustpower and their collaborators on site: NDT inspections, metallurgical investigations, etc.
The conclusion of LDV’s assessment was that:
- The cracks in the rotor spider likely occurred during the original unit commissioning;
- The rotor spider was safe for normal operating condition;
- The rotor spider could not be confirmed structurally fit to withstand a runaway event;
- Practical structural modifications could be implemented on site to make the rotor spider safe under an accidental runaway condition.
R.H. Saunders GS Hatch Covers Refurbishment
Client : Champlain E P&C
Location : Cornwall, Ontario
Year : 2021
As part of the hatch cover refurbishment project for the 16 units of the R.H. Saunders Generating Station (GS) for OPG (Ontario Power Generation), Champlain E P&C, a company specialized in Electrical systems, Protection and Controls for hydro generation plants, commissioned LDV Consultants to be responsible of the mechanical parts. The refurbishment works required to design or modify the opening and closing, sealing, and draining systems of the hatch covers. In addition, seal heaters, guardrails, limit switches, and door latches needed to be integrated.
As part of the refurbishment project of the hatch covers at R.H. Saunders GS, LDV Consultants was responsible to perform the following tasks:
- Calculation of the power chain for the hatch covers opening and closing;
- Evaluation and selection of components;
- Design and integration of mechanical components and systems:
- Opening and closing, sealing, and draining systems;
- Seal heaters, guardrails, limit switches, and door latches.
- Preparation of the fabrication and installation drawings;
- Preparation of installation procedures;
- Site installation support and commissioning.
Refurbish Generating Units of Côte Ste.Catherine Power Plant
Client : Delom Services
Location : Sainte-Catherine, Quebec
Year : 2021
Delom Services was awarded a contract to refurbish the generating units #10 and #7 at the Côte Ste.Catherine power plant, and mandated LDV Consultants to provide the engineering for the following:
- Disassembly and reassembly:
- Provide work procedures and data sheets;
- Prepare hoisting instructions;
- Validate lifting equipment and specialized tooling.
- Repair work to be done in the plant and on site:
- Analyze data from inspection sheets and non-destructive test reports;
- Write reports with recommendations and work instructions;
- Size the parts to be replaced/manufactured;
- Draft the procedures for reassembling the Kaplan wheels in the workshop;
- Resolve anomalies and non-conformities;
- Ensure the presence of a contact person on site;
- Provide engineering support.
Platforms for the Installation of Spiral Casings
Client : Voith Hydro
Location : Fort St.John, B.C.
Year : 2020
As part of its engineering, procurement and construction project for the new Site C power plant, Voith Hydro mandated LDV Consultants to design the platforms used to install spiral casings.
As part of the mandate, LDV Consultants carried out the following:
- Design the scaffolding, walkways and platforms used to assemble and install spiral casings in the power plant;
- Calculate and size components according to applicable standards and OH&S requirements;
- Produce manufacturing and installation drawings;
- Provide support during manufacturing.
Expertise for Embedded Parts, Air Gap and Model Test
Client : Rio Tinto Alcan
Location : Alma, Quebec
Year : 2020
Rio Tinto Alcan mandated LDV Consultants to carry out analyses and make recommendations on several subjects pertaining to a generating unit at the Isle-Maligne power station:
- Analyze and produce a report on the embedded parts of the turbine by an expert in turbine mechanics:
- Analyze the current condition of the parts;
- Make recommendations for the refurbishment and repair of each of the embedded parts;
- Extend their operating life;
- Assess the impact of the increased turbine power on the embedded parts and make recommendations on the adjustments to be made to the turbine.
- Analyze and produce a report on the evolution of the air gap by an expert in alternator mechanics:
- Analyze the current condition of the alternator in an advanced state of wear;
- Assess the impact of a breakdown on various components due to the state of degradation of the unit;
- Assess repair options to ensure proper operation of the alternator until it is rebuilt;
- Make recommendations on the monitoring and operation of the unit until it is refurbished.
- Express an opinion and produce a report on the anticipated performance based on the digital simulations compared to a model test, by a turbine hydraulics expert:
- Review the characteristics and guaranteed performance of the equipment;
- Make recommendations on the need for a model test while taking into account guarantees, costs, and deadlines.
- Propose a strategy for the upcoming major refurbishing of the 12 generating units to minimize the risks for the plant operator:
- Use new or refurbished parts;
- Plan the equipment downtime for refurbishment;
Hull 2 – U1 & U2
Client : Integrated Power Services
Location : Ontario, Canada
Year : 2020
Integrated Power Services is the leading provider of electric motor and generator repair services in North America.
IPS is responsible for the rehabilitation of 2 horizontal generators at Hull 2. The supply includes new winding coils for 2 stators.
LDV's mandate is to support IPS for the duration of the project and manage the interfaces.
- Design of the main and neutral leads to connect the winding to power transformer;
- Instrumentation schematics, junction boxes;
- Special tools for bearing handling;
- Collector rings drawing;
- Procedure for shaft alignment with turbine.
Bear Swamp rehabilitation
Client : Brookfield Renewable
Location : Gatineau, Quebec
Year : 2019
Brookfield Renewable is a world leader in alternative asset management. They are also one of the world's largest investors in renewable energy. They have assets located around the world which include a diverse technology base.
To monitor the Bear Swamp rehabilitation project, Brookfield Renewable mandated LDV Consultants during the design, manufacturing and implementation site phases to deliver the following engineering services:
- Review of all technical documents issued by the manufacturers to validate conformance with the contractual requirements, but also according to the industry’s best practices;
- Participate in design reviews as a Brookfield technical representative to review the proposed design, to identify potential design pitfalls or limitations;
- Review the technical aspects of the derogations, NCR and extra work occurring during the manufacturing process (and later during the site phase);
- Review the manufacturing shops ITP to propose witness points;
- Act as the technical and quality representative of Brookfield for witness point during the manufacturing process.
Technical Support - Modification of Sill Seal
Client : Major North American Company
Location : North America
Year : 2019
As part of a gate repair project, a major North American company commissioned LDV Consultants to design the modification of the existing intake gate in a hydroelectric facility. The repair work required the addition of a rubber sill seal to control the increasing leakage flow of the metallic seal. In addition, LDV Consultants provided support for the future refurbishing works of the intake gates.
As part of the technical assistance mandate for the intake gates, LDV Consultants has been mandated to perform the following tasks:
- Design of an added rubber sill seal;
- Drawings of new parts;
- Assembly drawing of the new concept;
- Validation of the wheel loads;
- Validation of the operating loads;
- Evaluation of the lifting system capacity;
- Modification of the lifting system to remove the clutch;
- Modification of the control system.
Refurbishing the Generator at the Jim-Gray Power Plant
Client : EnerServ - Resolute Forest Products
Location : Saguenay, Quebec, Canada
Year : 2019
As mandated by EnerServ, LDV Consultants performed the engineering required to replace and refurbish the generator and alternator components for the Jim-Gray power plant turbine refurbishing and waterwheel replacement project.
- Provide the engineering needed to disassemble, refurbish and reassemble components:
- Generator alternator shaft;
- Generator instrumentation;
- Turbine case;
- Gate-operating mechanism;
- Generator shaft;
- Generator shaft gasket;
- Guide vanes;
- Head cover;
- Head base;
- Draft tube.
- Provide the engineering for the follow-up of non-conformities during project implementation;
- Provide technical support during disassembly and reassembly;
- Provide hydraulic support during commissioning and adjustment of the ventilation system.
End Results
The existing components were dismantled, inspected, refurbished and reinstalled. The unit was commissioned on time and on budget. The performance of the refurbished unit fully met the client's expectations.
Engineering Assessment of Wells Damn Hydroelectric Project
Client : Toshiba America Energy Systems Corporation
Location : North America
Year : 2018
Toshiba America Energy Systems Corporation is a leader in the high-technology industry of engineering and construction that provides customer service for all energy platforms (hydro, nuclear, thermal…) like turbine sales, repairs, etc. Toshiba America Energy Systems mandated LDV Consultants to carry out the initial engineering assessment of Wells Dam Hydroelectric Project:
- Review equipment technical specifications, TAES’ refurbishment design drawings and procedure, and units 1 & 2 refurbishment results with the objective of identifying the engineering potential improvement actions and priorities and put them in a report for TAES’s management;
- Assist Toshiba’s engineering to address the top 4 priorities for the Wells Dam Hydroelectric Project with the compilation of all the documentation pertaining the priority being addressed, in depth analysis of the information collected, drafting and review of a proposed action plan with Toshiba and issuance of drawings, procedures and site data sheets necessary to reach the agreed-upon goal;
- Perform limited-scope mandates in support of Wells Dam refurbishment engineering, task details (deliverables, schedule, maximum hours) to be determined for each mandate.
Technical Support - Gate Wheels Modification
Client : Hydro Tech - OPG (Ontario Power Generation)
Location : Ontario, Canada
Year : 2018
As part of a gate repair project, Hydro Tech commissioned LDV Consultants to design the modification of the intake gate wheels at the Kipling hydroelectric facility. The repair work required the replacement of the bearing elements as the existing wheels were seized. In addition, the original design had to be modified in order to use commercial bearings instead of custom-made elements to limit the duration of the work.
As part of the technical assistance mandate for the design of the valve wheel modification at Kipling, LDV Consultants was mandated to perform the following tasks:
- Selection of bearings;
- Drawings for repairing and modifying preserved parts;
- Drawings of new parts;
- Assembly drawing of the new concept;
- Supply of bearings;
- Workshop assembly procedure;
- Installation procedure for wheels at the site.
Turbine Shaft Fea Assessment
Client : GE Renewable Energy Canada
Location : USA
Year : 2018
As part of a submittal requisite, the owner wanted to have a preliminary study of the turbine shaft structural integrity in order to assess if the component was robust enough to undergo another 40 years of service life in addition to a power increase.
LDV's Mandate:
- Perform a FEA analysis of the turbine shaft to better understand its physical behavior under its normal and steady state load conditions;
- Calculate by finite element analysis (FEA) the Von-Mises equivalent static stresses in the turbine shaft at full load in normal operating conditions and compare the results against the criteria commonly used in the hydro business;
- Calculate by FEA the Von-Mises equivalent static peak stresses in the turbine shaft for different fatigue cycles and compare the results against S-N fatigue curves commonly used in the hydro business to evaluate the cumulative fatigue damage;
- Calculate by FEA the maximum allowable crack which is not propagated under the maximum load in normal operating conditions using the methodology found in the API579-1/ASME FFS-1 Standard.
The preliminary finite element analysis showed that the base material of turbine shaft is robust enough to withstand an additional 40 years of service life and a maximum allowable crack size was identified.
Finite Element Analysis of the Pole and Rim
Client : New Zealand Operator
Location : New Zealand
Year : 2017
Following the inspection of the units of a New Zealand operator's hydroelectric power plant, LDV Consultants was mandated to conduct an analysis on the units of the hydroelectric power plant to draw up a series of recommendations and inspections for future unit shutdown. As part of the project, LDV Consultants was mandated to conduct a finite element analysis on the rotor trunnion pole and rim.
The purpose of this analysis was to determine the actual condition of the rotor's two main components given that the units, that are operational since 1967, have never undergone any major refurbishing.
The purpose of the finite element analysis was to determine the stresses and deformations of the rim and pole under various loading conditions so as to calculate their remaining useful life. Static stress and fatigue damage calculations were therefore performed as per the recommendations in the ASME Boiler and Pressure Vessel Code, Section VIII, Division 2. The analysis was conducted, using ANSYS Workbench r.18.2, on an assembly that included the rim and pole.
FEA of a MIV
Client : Major North American Company
Location : North America
Year : 2017
As part of a vast rehabilitation and certification project for its production units, a major North American company mandated LDV Consultants to perform a finite element analysis (FEA) of large main inlet valves (MIV) installed in a power plant.
The purpose of the FEA was to determine the best solution, i.e. to replace or rehabilitate the MIV, from an economical point-of-view, but also from a safety perspective as the MIV plays an essential role in the safety and integrity of the turbine parts, generator parts and entire power plant.
To achieve this objective, the stress fields and deformations under several load conditions were calculated by FEA. The different load conditions were then combined to evaluate the theoretical residual operating life of the MIV. The stress and cumulative fatigue damages were calculated and verified in accordance with the ASME Boiler & Pressure Vessel Code, Section VIII, Division 2 methodology and criteria. The FEA was performed using Ansys Workbench 17.2.
Technical Support Côte Ste-Catherine Power Plant
Client : Delstar Énergie
Location : Sainte-Catherine, Quebec
Year : 2017
Delstar Énergie, a subsidiary of Groupe DELOM, is a well-known player in the world of energy, particularly in regard with generator poles and electrical conductor refurbishment or fabrication.
To get the support of hydro generator experts, Delstar Énergie contacted LDV who provided its engineering services for the refurbishment of one 1,6 MW turbine-generator unit, that comprised a Kaplan runner with single regulation.
- Site support for dismantling and reassembly of turbine and generator unit;
- Dimensioning of new runner blade bushings;
- New design of blade seals;
- Shop support for machining of runner components;
- Definition of technical requirements for pressure and balancing tests;
- Recommendation on assembly tolerances and guide bearing clearance;
- Writing of the in-shop runner assembly/disassembly procedure.
In order to provide a high-quality service and to establish an effective collaboration and communication with Delstar’s personnel, LDV's experts made several trips to the plant or the site during the project.
Gate Replacement of Latchford Dam
Client : Rouby Industries
Location : Latchford, Ontario
Year : 2016
Rouby Industries specializes in the manufacturing of metal structures and structure parts, and more specifically hydraulic structures. During the refurbishing of the Latchford dam, Rouby Industries was tasked with designing, manufacturing and delivering equipment used to control the water level of Bay Lake.
Rouby Industries mandated LDV Consultants to provide assistance during the design and manufacturing of various components, including the gate, embedded parts and hoisting device as well as the steel cofferdams, wood beams and steel guide rails to ensure that the design and manufacturing comply with the client's requirements and Canadian standards (CSA S16). As part of its mandate, LDV Consultants carried out the following:
- Verify and validate the engineering, including the design notes for the components;
- Check and certify the assembly and detail drawings;
- Design and layout of the electrical control panels to heat the gate, embedded parts and gate
- Control system;
- Design and layout of the electrical control panels for the gate hoisting device.