Power plant owners and operators have entrusted their turnkey turbine-generator overhauls to MD&A for close to four decades.

Our team of seasoned professionals has a broad range of experiences whose skill sets cover both common and unique makes and models of turbo machinery from around the world.

Our reputation for providing objective advice, effective project management, and high-quality repairs has enabled MD&A to become one of the most recognized and trusted names in the power generation industry.

We are your full-service, OEM-alternative gas turbine service provider!

View our new Gas Turbine Services’ capabilities video below and then call Gas Turbines Services today at (518) 399-3616 or use our Contact form.

Mechanical Dynamics & Analysis provides power generators around the globe with a full-service, OEM-alternative for your gas turbine. We provide the expertise necessary to address both planned and forced outages of many types of gas turbines.

Our routine maintenance capabilities range from a full Major Inspection to a Combustion or Hot Gas Path Inspection. We perform specialized services, such as performance testing and analysis, aligning gas turbine internal components, replacement, and alignment of compressor discharge casings and turbine shells.

MD&A’s Gas Turbine Rotor Repair Division in St. Louis, Missouri has the expertise for superior repair solutions. Our fully equipped one-stop shop has validated tooling for unstack, restack, inspection, balance, and repair for gas turbine rotors. MD&A has developed complete engineering models and inspection procedures to support various plant strategies for Rotor Life Assessment and Life Extension.

MD&A’s San Antonio Service center is an industry leader in gas turbine component repair. Our team has extensive knowledge on gas turbine hot gas path and combustion components. MD&A’s advanced coating system, on components, can provide oxidation and corrosion protection, and aid in temperature reduction.

We test and repair gas turbine fuel nozzles. MD&A supports multiple frame’s Standard Combustion, Multi-Nozzle Quiet Combustor & Dry Low NOx System 1.0, 2.0, and 2.6 systems.

Our experts offer refurbishment of gas turbine bearings. We stock replacement bearings to satisfy short-cycle turnaround requirements.

MD&A Generator specialists perform turnkey stator and field rewinds, and repairs of any type or OEM. We conduct full-scope electrical testing, visual inspections, and specialty tests, per customer requirements.

On staff, we have experts who specialize in Engineering Parts & Retrofits for Control and Excitation Systems. Our HMI simplifies power plant control and monitoring.

The post Gas Turbine Services Video appeared first on MDA Turbines.

Our Turbine-Generator Repair Facility experts understand the importance of having a well-maintained and properly functioning gas turbine. That’s why we make repair recommendations based on the owner’s intended operating plans for the unit. This ensures that our clients receive the best possible recommendations for gas turbine repairs.

We pride ourselves on our effective and time-tested principles that allow us to produce sound and superior repair solutions for gas turbine-generator rotors and components. Our team has the knowledge and expertise to address all types of gas turbine issues, ensuring that your power generation plant runs smoothly and efficiently.

Why choose MD&A?

For over 40 years, our commitment to excellence has earned customer trust for all turbine-generator needs. We focus on delivering consistent quality and value with fast response, superior communications, and innovative solutions.

MD&A is easy to work with. We provide immediate access to expert help when you need it, where you need it. Around the corner or the globe, we ensure prompt, thorough communication, and follow-through. For every repair job, large or small, the speed and effectiveness of our response team are matched only by the depth and breadth of our engineering expertise.

Find out today why so many power generators use MD&A to maximize operational effectiveness.

The Gas Turbine Repairs capabilities that we offer include the following:

1.       Rotor Repair

MD&A offers full capabilities for your gas turbine rotor maintenance and end-of-life assessment. Our one-stop-shop, Turbine-Generator Repair facility in St. Louis, MO, is equipped with overhead cranes, a 100-ton lathe, and all support equipment for inspections and repairs.

2.       Component Repair

Our gas turbine experts are highly focused on providing quality gas turbine component repairs. Our team is trained in many types of component repairs, like dimensional restoration, blend repair, weld repair, and machining for combustion and gas path components of multi-frame gas turbines

3.     Fuel Nozzle Repair

Our Fuel Nozzle Services Division provides refurbishment and repairs of fuel nozzles in gas turbines. Our experts provide services for GE® gas turbine Frame 5 fuel nozzles, Frame 7 fuel nozzles, Frame 6 fuel nozzles, and Frame 9 fuel nozzles including standard, Multi-Nozzle Quiet Combustor (MNQC), and Dry Low NOx System (DLN) 1.0, 2.0, and 2.6 for industrial and power generation customers.

4.     Machining Services

We offer a wide variety of portable gas turbine field machining and steampath repair services to use on-site. Our Turbine-Generator Repair Facility machining capabilities include in-shop and on-site repair horizontal joints for turbine casings, defective rotors, valves, or other turbine-generator components.

5.     Portable Machine Shops

We have multiple portable machine shops available for use during plant projects. Clients can also use these shops during an outage. Our shops are available in portable Conex trailers and are fully stocked with drill passes, metal grinders, lathe, and many other essential tools

6.     Compressor Vane Pinning Solutions

Multiple power plant owners notice shim migration and compression rocking issues. Our highly skilled professionals have expertise in gas turbine repair techniques and leading-edge equipment for these issues.

7.     Bearing Ball Ring Repairs

MD&A’s Bearings, Seals, and Hydraulics division performs precise journal bearing ball ring repairs utilizing our horizontal bore machine. We provide a complete restoration to the spherical fit and can perform checks to ensure proper assembly on site.

8.     Rapid-Spares Gas Turbine Bearings

MD&A Bearings, Seals & Hydraulics Division can handle bearing-related issues with the help of pro-active planning. The Rapid-Spares bearing exchange reduces the uncertainty of the bearing refurbishment conditions at the time of critical outage intervals.

9.     High-Speed Balance

Our high-speed balance facility in St. Louis, MO is designed with vacuum capabilities and the ability to excite generator rotors at high speed. This allows our engineering specialists to handle turbine and generator-related balancing and testing effectively.

10.   Elliptical Journal

We design, repair, and manufacture elliptical bearings to remove the steam whirl or oil whip side effects of your gas turbine. We also provide short cycle delivery, insulation mounting and spherical mounting restoration, and performance monitoring instrumentation.

11.   Tapered Land Thrust

MD&A’s Bearings, Seals & Hydraulics Division can manufacture, and repair tapered land thrust bearings. We can provide material upgrades, fixture profiling, instrumentation in performance monitoring, and short cycle delivery.

12.   Tilt Pad Thrust

A tilt pad thrust bearing retrofit is a cost-effective solution when sole plate settling or other foundation changes have created poor alignment conditions. We offer clients predictable bump check shim sizing and complete assembly reconditioning.

13.   Bronze Turbine Seal Rings

The Bearings, Seals, & Hydraulics Division at MD&A provides a range of bronze turbine seals rings that include manufacturing to spec, in-house stocking of custom alloys, and expedited delivery on a short cycle.

14.   Oil Deflectors

MD&A Bearings, Seals & Hydraulics Division offers complete oil deflector reconditioning to assure the long-term integrity of a tight oil sealing system. Our inventory includes seal tooth material, dowels, steam painting/cleaning, and body bolt components.

15.   Tilt Pad Journal

One of the gas turbine repairs we offer is tilt pad journal bearing retrofits. A tilt pad journal is useful for managing the effects of steam whirl or oil whip conditions. We offer complete assembly, provide material upgrades, performance monitoring instrumentation, and short cycle delivery.

Conclusion

Our skilled and experienced team of experts is invested in providing high-quality testing and gas turbine repair services. With our help, you can improve the operating conditions of your unit and discover any underlying issues that may be affecting your fleet. Talk to one of our experts and discover all the repairs we offer, get in touch with us as soon as possible.

Sign Up for MD&A’s Insight Newsletter: Get quarterly our turbine-generator expert’s case studies and tips!

The post Overhaul Gas Turbine Repairs appeared first on MDA Turbines.

Common issues to investigate are stator vane rocking tilt, fretting wear in the T-slot groove, shim protrusions or migration, and possible airfoil clocking. The potential for foreign material damage should always be considered when reviewing stator vane conditions.

These issues can lead to performance efficiency loss, damage to both compressor and turbine sections, and potentially a forced outage event. At risk are both Frame 9FA and 7FA machines, as well as many others.

For this project, Our Gas Turbine Parts Service Facility (San Antonio Service Center) was contracted to manage and perform casing preparation, stator vane removal, vane repair, or replacement as needed, pinning, shims, reinstallation, and final horizontal joint drop dimension adjustment and verification.

The Process

The upper half compressor mid and discharge casings were removed and placed vertically on cribbing for vane access. With the rotor out, all upper and lower stator vanes were then removed in rows S5 through S16 for vane and casing inspection.

Several vanes had the OEM shim TIL pinning solution installed by others in a previous outage. Most shims showed considerable looseness around the countersunk pin head and many were not well retained, falling loose during removal. Continued operation could have led to shim ingestion, downstream blade damage and forced outage.

During the inspection by MD&A field service personnel, most stator vanes were deemed acceptable for reuse. Galling and fretting were minor, and most hook fits were in good condition.

Some stator vanes exhibited damage on various locations on the airfoil and base and required replacement, most of these replacements were on Stage 16 (38 upper, 7 lower).

The required vane replacements (provided by the customer) were drilled as required for pinning along with the rest of the non-replaced stator vanes to ensure proper alignment upon re-installation. For those stator vanes being reused that contained old broken pins, these pins were either drilled out or secured to ensure no future movement. Stator vanes that contained the TIL pinning condition were either used as a single centerline pin in Stages 5 through 12, or drilled and pinned on the side not affected by the TIL, then placed at the ends of vane groupings during reinstallation.

MD&A directed and oversaw all stator vane drilling and pre-installation inspection and provided the machining fixtures needed to hold individual vanes at the correct drilling orientation. Rows S5 through S12 were pinned in either a single configuration, except those closest to the horizontal joint were pinned in a double pin configuration to provide increased robustness. Rows S13 through S16 received all double pins both upper and lower.

All casing grooves were inspected and cleaned. Vanes were then reinstalled in both upper and lower casings in the planned 4- to 6-vane sectors.

Final shims were installed as needed to achieve OEM guidelines for joint drop dimensions. A total of 67 shims were installed along with the 1,332 vanes.

The unit returned to service with MD&A’s recommendation for periodic borescope inspections in line with OEM guidelines.

The Experience

The stator vane and shim pinning process reduces wear during both start/stop and long-term operation. More than 200 gas turbines are operating with vanes pinned by the MD&A process. These units are successfully operating in Frame 7EA, 9E, 7FA and 9FA turbines.

MD&A’s San Antonio Service Center provides proven expertise on multiple frame gas turbine combustion and hot gas path components and is an F-Class Repair Center of Excellence.

The dedicated professionals throughout MD&A excel in site-based and condition-specific analysis and repair. Maintaining site schedules is always a priority.

Call MD&A today for your Compressor Stator Vane Pinning at +1 (210) 256-5000 or use our Contact form.

The post Compressor Stator Vane Pinning appeared first on MDA Turbines.

During their planned major inspection, the utility decided to remove the rotor based on prior recommendations from past borescope findings.

Upon inspection, our gas turbine experts discovered that the Row 1 turbine wheel showed indications of heavy wear caused by rubbing to the rear face of the discourager seal. To repair this, the seal area was prepped and built up using a spray metallizing process.

Once the precise build-up was achieved, the seal area was ground to the correct dimensions and contours. In addition, wear damage to the Row 2 turbine disc sealing area was repaired to achieve an acceptable surface after a fluorescent penetrant inspection was completed.

Experts also performed compressor blade blending from wear damage/FOD to all compressor blade rows. One Row 16 blade was removed and replaced, and non-destructive testing was performed on the repaired rotor.

Progressive balance work was completed on two turbine bucket stages. MD&A experts replaced both stages of buckets.  

Our experts also performed the modification to the gas turbine rotor which involved machining the thrust runner face that is located at the No. 1 bearing. This is a common recommendation for the Frame 5 fleet to improve the reliability and operation of the thrust bearing.

Skilled technicians from MD&A’s Bearings, Seals, and Hydraulics Division re-toothed the rotor’s oil deflectors and re-babbitted the bearings.

New replacement buckets were provided by MD&A Parts. The rotor was progressively low speed balanced as the 1st and 2nd stage buckets were installed, technicians secured balance weights and completed the six-point residual unbalance test.  The rotor was then packaged & secured on the shipping skid.  Finally, MD&A transported the rotor to site and successfully supervised the re-installation.

MD&A’s specialized services range from Combustion, Hot Gas Path, and Major Inspections to Compressor & Turbine Rotor Repairs and End of Life inspections. MD&A offers a complete suite of parts, repairs, and services solutions for the Frame 5 gas turbine fleet.

Call our MD&A Gas Turbine Services today at (518) 399-3616 or use our Contact form

The post Frame 5 Gas Turbine Rotor Repair appeared first on MDA Turbines.