Our experts have over 15 years of experience in repairing single crystal gas turbine blades. We have repaired over 4,000 blades made of materials equivalent to the 7FA.04 1st blade (Rene-N4).

7FA.04 components can be repaired using MD&A’s procedures which aim to extend their life while enhancing performance.

Repairing 7FA.04 Buckets:

MD&A has also developed a comprehensive repair process for 7FA.04 1^st stage buckets, addressing various issues commonly observed in the incoming condition. Problems such as tip cracks, tip cap oxidation, and wall thinning, as well as airfoil TBC coating missing with oxidation through the bond coat and into the parent material.

The 7FA.04 1st stage bucket tip restoration process includes the removal of all cracks and airfoil damage, single crystal proprietary weld processes using high-quality materials, and the installation of a new tip cap.

MD&A implemented CT Scanning (3D X-ray) and white light scanning to develop the optimal welding techniques to ensure a top-quality tip welding restoration structure.  Metallurgical testing was performed to ensure that the process produced buckets free of cracks and re-crystallization at the airfoil tip cap.  The weld material above the tip cap is a high oxidation and erosion resistant structure that is proven to perform well in single crystal blades at high firing temperatures experienced in AGP applications.

The final configuration of the blade tip is accomplished by using a multi-electrode configuration tool during the electrical discharge machine process (EDM).  After re-establishing the tip geometry, all new cooling holes are established to ensure proper tip cooling.  The tip restoration technique ensures no double or triple drilling cooling holes.  This provides the best airfoil tip cap integrity.  All components are then x-ray inspected and airflow tested.

Once the repairs and pre-coat inspections are complete, MD&A experts apply a NiCoCrAlY HVOF bond coat.  This coating is derived from military gas turbine technology and contains additional elements such as Hafnium and yttrium that provides for a superior oxidation resistant bond coat.  MD&A offers a low conductivity (Low-K) Thermal Barrier Coating that helps reduce the bulk operating temperature of the 7FA.04 1st Stage bucket.  Lowering the operating temperature provides for the long-term preservation during the operational lifespan of the component.

The MD&A blade tip restoration technique has been fully demonstrated in directionally solidified (DS) and single crystal (SC) components.  Evaluation and measurements of blade tip repairs after operation have demonstrated improved optimization of the blade tip height.  Keeping most of the original tip height during operation provides the best turbine performance.

In one case study comparison versus the OEM, MD&A’s blade repair procedures have proven to be highly effective, resulting in several benefits for customers. These include minimal loss of blade tip height, which helps maintain turbine performance, as well as, low erosion and oxidation of the repaired blade tips. MD&A’s repairs also exhibit excellent abrasion resistance against the thermal barrier coating (TBC) of 1st shroud tiles.

MD&A has successfully repaired over 4,000 single crystal blades, resulting in approximately millions of dollars of savings for customers. These repairs have enabled blades to operate at higher firing temperatures, contributing to improved turbine efficiency.

Experts in AGP Gas Turbine Component Repairs

MD&A has also performed inspections on 7FA.04 (AGP) 2^nd Stage Blades & 3^rd Stage Blades.

Our facility has leading-edge equipment and repair techniques with proven expertise on multiple-frame gas turbine hot gas path and combustion components.

Our team has extensive knowledge on a range of gas turbine component repairs, including weld repair, blend repair, dimensional restoration, and machining.

Our expert technicians are well-trained, seasoned professionals with in-depth knowledge of the many strict tolerances, procedures, and specifications to complete each repair.

Repairing Nozzles & Shrouds:

MD&A experts have also repaired 7FA.04 1st shroud tiles. This repair involves implementing true abradable coatings in new and repaired tiles to minimize stress on the blade tip during rubbing incidents.

MD&A’s repair expertise extends to gas turbine nozzles, including the 1st and 2nd stages.

Similar repair experience are Nickel-based V94.3A2 2nd and 3rd vanes with our weld/braze repair method refined over 15 years. Our experts have successfully repaired 45 sets and returned them to service.

For 7FA.04 2nd stage nozzles, our experts have made an alloy change and combined weld repair with braze repair.

MD&A specializes in the repair of several key gas turbine components across different models, allowing our customers to extend the lifespan of their equipment and optimize operational efficiency.

1. 6FA/7FA/9FA Repairs: We offer comprehensive repairs for the 1st, 2nd, and 3rd buckets, nozzles, shroud blocks, liners, transition pieces (TP), flow sleeves, and caps in 6FA, 7FA, and 9FA gas turbines.
2. 7EA Repairs: Our expertise extends to repairing 1st, 2nd, and 3rd buckets, nozzles, shroud blocks, liners, transition pieces (TP), flow sleeves, and cowl caps in 7EA gas turbines.
3. V94.3A and V84.3A Repairs: We provide repairs for 1st, 2nd, 3rd, and 4th blades, 1st, 2nd, 3rd, and 4th vanes, as well as the 1st outer seal in V94.3A and V84.3A gas turbines.
4. GT24/GT26 Repairs: Our repair capabilities encompass HPT1 blades/vanes and LPT1, LPT2, LPT3, and LPT4 blades/vanes in GT24 and GT26 gas turbines, with ongoing development in the repair processes.

MD&A is an industry leader in AGP gas turbine component repairs and has earned customer trust across the globe. Our expertise in repairing various gas turbine models allows our experts to constantly sharpen their skill set and brings both depth and breadth of experience to your parts lifecycle. We believe our historical track record of success is an important fact that differentiates our service from those available elsewhere in the industry.

Through meticulous repair processes and commitment to continuous improvement, MD&A delivers cost-effective solutions, enhanced performance, and extends the lifespan of gas turbine components.

For more information about our AGP gas turbine component repairs and services, please visit our website or use our contact form.

The post 7FA.04 (AGP) Gas Turbine Component Repairs – Enhancing Performance and Cost Savings appeared first on MDA Turbines.

View our Gas Turbine Component Repair video below and then call MD&A San Antonio Service Center today at (860) 781-3152 or use our Contact form.

MD&A’s San Antonio Service Center provides repair services for large-frame gas turbines, with proven expertise on frame 7EA, 6FA,7FA, 9FA, V84, and V94 combustion and hot gas path components.

All of the repair processes, with the exception of acid stripping, are completed in house, utilizing our Three-Stage Gate Process to ensure the highest of standards.

Each gate provides the client with an important checkpoint to review the project’s progress with our engineers — a partnership that enhances quality and reduces repair time.

The first step of MD&A’s gate process is referred to as Strip and Inspect.

When a component first arrives in San Antonio, we conduct an Incoming Inspection – tagging and cataloging each part.

This stage includes Airflow and Dimensional Inspection then a Fluorescent Penetrant Inspection, or FPI, which uses blacklight technology to pinpoint any cracks.

The Ultrasonic Inspection is a completely automated, ultrasonic underwater test that provides thirty-eight points of precise measurement.

All of MD&A’s crews are certified in their specific area of expertise.

Gate Two is the Repair stage.

With the goal of returning a part to its original state, this stage begins with a Solution Vacuum Heat Treatment Process.

CNC machining delivers cuts that are precise and uniform every time.

MD&A utilizes the industry’s most advanced Welding techniques, including hot box and hand blending, with individual welding booths assigned to each part.

Unlike hand drilling, Electro Discharge Machining, or EDM, assures part conformity.

Once repairs are completed, a report is compiled; review of this report is another checkpoint opportunity for our experts and clients.

The last stage of the Gate Process is the Final Inspection.

Once a part has gone through another visual inspection, it is ready for Coating, a thorough process that ensures a precise application. HVOF, or High-velocity oxygen fuel, is a base coat applied at the speed of sound. A proprietary 3-layer Thermal barrier Coating (TBC) System is applied to High-technology components using our vertically cracked Ultra–Dense Coating System (UDC).

Because MD&A’s proprietary coatings can sustain the high temperatures that hot gas path components are subjected to, our coatings also extend the life of the components.

Parts are then weighed during Moment Weigh and go through Sequencing to balance the turbine perfectly.

The final Inspection includes a detailed review of the component report, ensuring each step was performed completely.

A full-service, OEM-alternative for gas turbine components and repairs, MD&A delivers industry-leading solutions with processes and parts that are backed by guarantees.

The post Gas Turbine Component Repair appeared first on MDA Turbines.