Outage Planning Services

Pre-Outage Planning

A Customized Plan

Most power producers are short-staffed and do not have the time and sometimes the expertise to prepare a comprehensive outage plan and workscope.  That’s why we offers the option of providing our comprehensive Pre-Outage Planning Service independent of the award of the contract for inspection and repairs.

Our field project teams have the breadth of knowledge and experience to produce the highest quality planning product, with a workscope customized to your unit and its specific signature.

One of our qualified Technical Directors will visit your plant and prepare a customized report for your specific unit.  The report will contain everything needed to plan your internal preparations for the outage and to prepare a comprehensive Request for Quote for the inspections and repairs.

 

A Basis For Your RFQ’s 

Your customized Pre-Outage Plan will include everything you need to prepare a comprehensive Request for Quote for the necessary inspections and repairs.  We will compile a summary of the findings from past inspections and develop a list of recommendations for potential repair work.  We will prepare a comprehensive and detailed suggested Statement of Work for the outage, based on these findings and observations from a unit walk-down.  Incorporating this information into your Request for Quote packages will yield “apples to apples” cost comparisons and few if any surprises on implementation.

 

A Task List For Your Facility

We will review your spare parts inventory and compile a list of recommended parts to have on hand prior to the outage.  We will recommend disposal of any expired or unusable spare parts.

We will also prepare a Critical Path Method schedule based on the defined workscope.  You can use this schedule to plan your expected outage duration and coordinate with any other activities to be conducted during this downtime.

 

What We Provide

The Pre-Outage Planning Package includes:

  • Outage History Review: We review your past outage reports to determine pending or implemented outage recommendations and any changes that may have been made to your unit.
  • Unit Walk-down: We perform a detailed walk-down of the unit, visually inspecting the components and auxiliaries that will help to develop a detailed pre-outage scope of work.
  • Customized Outage Workscope: Formulated from the on-site analysis of your unit, past outage reports, and known issues supplemented by discussion of particulars with you and your staff, we develop a workscope unique to the specifics of your unit and its current condition.
  • Outage Schedule: We take your customized workscope and create a comprehensive Critical Path Method schedule. This exceptional tool outlines a reasonable outage schedule and projected duration, and it can be used as a guide to measure the performance of your outage contractor.
  • Parts List: We compile a “recommended to buy” list determined by a physical review of your unit, prior outage report recommendations, and review of available inventory.

 

In summary, our Pre-Outage Planning deliverables to you will be:

  1. A scope of work tailored to your equipment and outage needs.
  2. A parts inventory and suggested purchase list (to support outage or emergency needs).
  3. A document to assist in the preparation of the scope for RFQ / bid documents.

 

Please CONTACT US today to learn more about how we can help you plan your next turbine outage.

Westinghouse 251B Gas Turbine Inspection

We were recently contracted to perform a modified Combustion Inspection on a Westinghouse 251B Gas Turbine by a customer in the United States.  Below is a summary of the activities we completed during this inspection.  All activities were completed with an attention to safety, and our quality processes, to ensure a successful outage completion.

Upon arrival for setup of tools the unit was shut down and locked out to perform the inspection. The necessary roof sections were removed for crane access to disassemble the components. All combustion parts were removed and replaced with new/refurbished during the inspection – pilot nozzles, support housings, baskets and transition pieces.

During this outage, the upper half compressor case was removed for the inspection of the R1 – R7 in the compressor section.

During this inspection, due to the condition of the compressor it was decided to remove two bottom R-1 vanes (#21 & #22) for a visual inspection and then reinstall.

The inlet access door was removed for inspection of the inlet scroll and the Inlet Guide Vanes. The Inlet Guide Vane angles were checked and verified. The row #1 compressor blade tip clearances were also checked. The Inlet Guide Vanes were greased after inspection. The inlet was cleaned and visually inspected by the plant personnel and our Technical Field Advisor prior to closing.

The exhaust was opened, and the bullet cone inspection cover was removed for inspection of the exhaust bearing pedestal. The exhaust struts were inspected, and cracks were repaired as needed by the site welding contractor.

The end result was another successful turbine inspection – zero safety incidents, quality work, and an on-time and on-budget outage completion.

Frame 5 Major Inspection

We were contracted to perform a Major Inspection on a Frame 5 Combustion Turbine for an Independent Power Producer in the Northern U.S.  Upon arrival the unit was shut down and locked out to prepare for the upcoming inspection. The necessary roof sections and inlets were removed for crane access to remove components. All combustion hardware was removed during the inspection – liners, cross fire tubes, and transition pieces.

During disassembly there was a great deal of broken bolting experienced on this unit, mainly due to the fact it is an outdoor unit that has not been disassembled in many years. These broken bolts were removed by a local vendor as well as the repair of the threaded holes. The combustion hardware was not in great condition, with cracked liners and high wear on the fuel nozzles.  The crossfire tubes were severely worn. Exhaust cooling air piping was also found to be severally corroded.  The inlet access door was removed for inspection of the inlet and the IGV’s. The IGV angles and clearances were checked and verified.  The row #1 compressor blade tip clearances were also checked. The IGV’s were cleaned for inspection.  After the inspection the IGV’s with excessive clearance had the bushings replaced. The inlet was cleaned and visually inspected by our Technical Field Advisor and plant personnel prior to closing. The main oil pump was disassembled and inspected; bearings were scored so they were replaced with new ones from the customer. The spline shaft had moderate wear on the gear teeth, and was replaced as well.

The 9th stage hook fit was cracked and corroded which necessitated the removal of the aft compressor case. This section of the compressor case was removed and sent to a repair shop. Upon return to the site the aft compressor case was reinstalled with all bolting torqued to support the lower half.

All refurbished and new hardware from the customer’s inventory was checked, with serial numbers recorded and marked for location.

During the inspection all the upper half cases were removed as well as the upper half nozzles – 1st and 2nd.  The upper half bearings were disassembled, and the rotor was removed. The number 2 bearing was found to be severally worn and out of tolerance. This allowed the rotor to drop and rub components in the lower half of the turbine section. All of the used lower half parts were removed and new or refurbished parts were installed. The rotor was cleaned, refurbished stage 1 buckets were installed, and the journals were lapped, then installed with refurbished bearings. The customer supplied new or refurbished stage 1 and 2 nozzles which were installed during the outage. All of the upper half cases were installed; all bolts were torqued per specification.

 

After completion of the unit the LOTO was released and the customer prepared for the test run. We were released from site after the unit was at 5MW’s and had excellent bearing vibrations.

Another great project by our Operations team, and another satisfied customer!

Frame 7B Combustion Inspection

PSG mobilized a Technical Field Advisor, Foreman, Turbine Mechanics, and Tooling to a Utility site in the southern U.S. to perform a combustion inspection ‘’CI’’ on a GE MS-7000B combustion turbine.

The job consisted of removing and replacing all combustion parts and associated consumables. The fuel nozzles, combustion liners and transition pieces were removed and replaced with OEM refurbished components.

The bullhorns, combustion chambers, crossfire tubes, retainer clips and lid covers were returned to service with no replacement necessary. Transition piece hardware was replaced with new parts and the crossfire tubes and retainer clips were returned to service with minor wear being noted. All associated flange gaskets were replaced with new OEM consumable parts in all 10 combustion cans as a preventive maintenance practice. New flange bolting hardware was also installed as a preventive maintenance practice.

The combustion wrapper was removed to better access the transition pieces and have a better visual inspection of the 1st stage nozzle, all wrapper case bolting was replaced with new upgraded components.

The inlet was visually inspected and found to be in overall good visual condition.

A visual inspection of the exhaust plenum showed the assembly to be in overall good visual condition with minor wear noted.

The end result was another successful combustion inspection on a Frame 7B combustion turbine, and most importantly, a satisfied customer.

The Right People

A company built on industry leadership, knowledge and experience!

We employ industry-experienced professionals who work together consistently as a cohesive team, anticipating problems and formulating best solutions. Our team approach allows us to better organize and manage your project details and plan for contingencies. This organizational structure creates a project team that runs smoothly… So your project runs smoothly too.

Project Management
Good project management is key to a successful outage. Our Technical Field Advisors and Foremen are industry veterans, with experience across all the units we service. Many of them started their careers with an OEM. They offer the technical and project management proficiency to guide your specific project and are qualified to provide clear options and recommendations when repairs are required.

Project Coordinator
The on-site Project Coordinator manages supplies, parts, services and contractors and reports costs on a daily basis. This allows us to manage your project with a single Technical Field Advisor, reducing costs and providing seamless control.

Turbine Mechanics
Each Foreman builds a base crew of Mechanics who work together consistently. We also provide formal training and advancement for a pool of mechanics who are utilized when larger crews are needed. Together, they have the necessary skills and experience, and know our tools, procedures and safety.

Remote Turbine Consultations

 

Power Services Group offers remote consultative services for those customers looking to resolve issues on their turbine power island.  Many facilities have postponed or delayed outages this year, and that may extend turbine run times to longer than some may be comfortable with.  Many turbines may have had outages planned to address issues currently being experienced.  Those outages are now postponed, and facilities must make alternative plans to address any operational issues.  At PSG, we can provide remote assistance to help you develop solutions to any potential problems you may be facing.  We will offer our opinion based on the information gathered remotely between your plant personnel and our qualified Technical Advisors.  This may include any operational data or photographs related to the issue being experienced, telephone conversations between involved parties, and remote video meetings by telephone to allow our Technical Advisors personally experience any sights and sounds that may be the result of the issue you are experiencing.  At PSG, we are here to help.  We understand that it may not be the most optimal time to have outside personnel visiting your facility, so we will do everything possible to help you develop alternatives through our remote consultative services with our qualified Technical Advisors.

We have expertise on most Steam Turbine OEM types (List of Steam Turbine OEMs we perform services on), as well as various types of Combustion Turbines (List of Combustion Turbine OEMs we perform services on).

You can call us at any time to begin discussions at 800-226-7557, or email us through the following link:  Contact Us.

If you ever experience an emergency situation, we have Technical Advisors just a phone call away at 888-MrTurbine.  We are available 24/7, 365 Days a year.

We look forward to helping you ensure your turbine is operating as efficiently as possible until your next turbine inspection.

 

Turbine Services Tool Containers

We’ve recently re-painted some of our tool containers – and they are looking good.  Nice work by our team at our Knoxville, Tennessee Logistics Center.

PSG maintains fully configured containerized tool sets, ready to be shipped to your location at a moment’s notice. The entire tool set fits on a single truck bed for ease in transport. Our logistics team is ready to ship these tools to meet your need – using best available rates for pre-planned outages, or expedited using 24- hour driving teams for emergencies.

Once we arrive at your site, we can quickly mobilize to efficiently begin work on your outage. If space and crane capacity is available, we can lift a container to your turbine deck and roll­ out our tool cabinets. If space is tight, we can lift the individual cabinets into place or transport them by forklift.

Our Project-Specific Planning allows us to customize the tool set for the job. We have what we need on-site, even planning for contingencies. The more organized we are, the more efficient our project teams can be, and that means less downtime for you.  Our fully-equipped trailers focus on safety and reduce labor costs so we can get your unit back online efficiently.

Specialized for Specific Needs

Besides Major Inspection tool sets we have developed many other customized sets including:

SAE/Metric

Steam/Combustion

Major/Minor/Valve & Bearing

Emergency Response

Organized for Efficiency

Our tools are organized for efficiency. Small tools are organized in movable heavy duty cabinets, with each drawer labeled in large letters. Tools are organized in foam cutouts within the drawer to make it easier to locate and replace a tool – a specific place for a specific tool. Large tools are organized in Gang Boxes, with hooks or pegs labeled for every tool.

We have a standardized arrangement for all our tool sets, so if a mechanic is familiar with one, he is familiar with all. Our mechanics take pride in our tool sets and retrieve and replace their own tools, as required, so there is no need for a tool attendant. This increases productivity and makes sure the right tool is used for every task.

Office Facilities

We bring a dedicated office trailer to facilitate project planning and communications. The trailer contains lights, power outlets and printers for management support, and is fully supplied with materials for lockout, badging, reporting and other support services.

After the tool boxes are removed from our separate tool container, it is used as a break room for our mechanics.

On-Site Repairs

If turnaround time is a critical factor in your outage, then we can perform most all machining and rotor repair using specialized portable equipment delivered to your remote facility. We will work with you during pre-outage planning to determine if this option is right for you.

On-site tooling is available for Rotor/ Seal Turning

Low Speed Balance

Broken Bolt/Stud Removal

Generator Rotor Rewind Collector Ring Grinding

Thermal Imaging of the Power Island

Thermography is a condition-based maintenance technique that is used to monitor the condition of plant machinery, structures, systems, and media (i.e. steam, oil, water, etc.).  By detecting thermal anomalies (i.e. areas that are hotter or colder than they should be), an experienced Thermal Imaging Specialist can locate and define incipient problems within the Power System.  Thermography is just one of the dynamic-state, running-condition assessment tools that can and will detect the presence of issues that may very well disappear during static-state preventive maintenance.  We highly recommend each plant conduct regular thermal imaging assessments of their equipment as part of their standard maintenance practices.

 

 

 

Gas Turbine Compressor Inspections

We recently completed the inspection of a Westinghouse Combustion Turbine Compressor Section.  This inspection can be performed standalone, or is typically performed as part of a Major Inspection.  It is imperative that the compressor section is free from defects and has proper clearances to allow air to flow toward the combustion section as smoothly as possible as pressure increases.  Executing the proper inspection procedures and techniques is imperative to any good Compressor Section inspection.  Our technicians have been trained on inspection and repair techniques for most major industrial combustion turbine compressor types from various OEM makes and models.  The expertise of the technicians performing the inspection is critical to successful future operation of the equipment.

Gas Turbine Compressor Degradation

Contamination and Erosion

All gas turbines experience losses in performance with time and the compressor has a significant impact. In a typical heavy duty axial compressor a 1.0% loss in compressor efficiency will create a 1.1% loss in output.

Compressor fouling is a serious concern and can be mitigated or recovered through proper operational practices. Dirt, oil and debris in the front stages of the compressor can result in a loss of mass airflow, and contamination in the last stages can result in power-robbing drops in the pressure ratio. These foreign objects can also erode or damage surface finishes and airfoil geometry, resulting in reductions in airflow and pressure ratios. Water-washing can partially clean contaminated blades, but recapturing full efficiency can only be achieved by opening the unit and mechanically cleaning the surfaces and replacing damaged components.

While the unit is open, the compressor can be coated to make the airfoils less susceptible to dirt and debris and increase the ability of the water wash to thoroughly clean the airfoils. Adding filtration to the inlet also helps maintain a clean compressor.

Leakage

In a typical heavy duty gas turbine compressor section, air is compressed to many atmospheres pressure by the means of a multiple-stage axial flow compressor. The compressor design requires highly sophisticated aerodynamics so that the work required to compress the air is held to an absolute minimum in order to maximize work generated in the turbine. Any changes to this precise geometry can materially affect performance.

Air leakage through and around components significantly rob performance. One example is a bleed valve which remains open during operation. Another would be a leak at the 4 way joint. While sealing the horizontal and vertical joints are necessary as the machine ages and the casing warps, sometimes all that can be done without purchasing new casings is to manage the leakage. Leaks are more costly to the aerodynamic cycle at stages further down the axial compressor. A leak at an early stage might not be worth the cost of repair.

At the tail end of the compressor rotor is the inner barrel, which provides the inner diameter flow path and the internal support for the exit guide vane (EGV’s). On the internal surface of the inner barrel there is a labyrinth seal called the high-pressure packing seal. On field inspections we often find significant rubbing of the rotor to the labyrinth seals of up to 90 mils. This excess clearance and thus increased airflow results in a loss in performance.

This leakage can be minimized by retrofitting the high-pressure packing seal area with a wire brush seal. The wire brush seal is flexible and will deflect (not wear) if it does contact the rotor. The bristles of the brush deflect in the direction of rotation so that a closer effective clearance can be maintained. The seal even remains intact during transient events where some vibration occurs. Also, there will be less performance degradation over time since the wire brush will bounce back to the original configuration after contact. These losses can only be repaired during an overhaul.

Calibration

Air temperature and pressure can seriously affect performance. Since the gas turbine is an air-breathing engine, its performance is changed by anything that affects the density and/or mass flow of the air intake to the compressor. When measuring performance degradation over time, remember to correct for changes to the reference conditions of 59 F/15 C and 14.7 psia/1.013 bar. Differing ambient air temperatures affect the heat rate. Correction for barometric pressure is more straightforward. A reduction in air density reduces the resulting airflow and output proportionately, but the heat rate and other cycle parameters are not affected.

Humidity is an often overlooked factor affecting performance. Humid air, which is less dense than dry air, also affects output and heat rate. In the past, this effect was thought to be too small to be considered. However, with the increasing size of gas turbines and the utilization of humidity to bias water and steam injection for NOx control, this effect has greater significance.

TGM can help you assess your unit’s existing performance versus its original design and establish a performance measurement process to accurately capture decreases which could indicate the onset of serious problems.

Turbine Generator Maintenance can help you achieve your goals in restoring your machine to its new and clean condition or upgrading its performance to achieve higher output, lower emissions or both.