The inspection revealed severe damage to the Stage 1A airfoils necessitating replacement of buckets. The Stage3 buckets were also replaced. For both rows, bucket hardware was supplied by MD&A and bucket covers were final machined to restore geometry.

In addition, both the L-1 stage & L-0 stage buckets and covers were replaced using material supplied by the customer. Our experts inspected the customer supplied buckets, confirmed critical criteria were met, provided consultation on a material substitution, performed the necessary activities to ensure properly balanced rows and machined bucket covers to restore geometry.

Additional rotor work included supply of a newly manufactured shrunk-on thrust collar and machining of the T1 journal. The overspeed trip was removed and tested by MD&A’s Bearings, Seals & Hydraulics Division. Experts also polished the 11th stage bucket admission edges to remove foreign object debris.

Inspection of the stationary components of diaphragms and packing boxes found some with excessive pitting on the packing groove axial steam seal faces. The seal faces were skim cut and custom packing was installed for these diaphragms and packing boxes. New spill strips were installed and machined for these same diaphragms.

Several diaphragm horizontal joints were weld repaired and restored to address joint indications and erosion damage. The nozzle bolt hole peening grooves were weld repaired, stress relieved and re-machined. The nozzle admission face was weld repaired, stress relieved and machined to restore axial clearance.

Finally, an inspection of the Curtis ring discovered it was out of round. The Curtis ring peening grooves and seal grooves were weld repaired and re-machined. The Curtis ring was bolted to the nozzle discharge face and stress relieved after the weld repairs were completed. This re-rounded the Curtis ring to fit into the nozzle tongue and groove fit. The Curtis seals were replaced and machined on-site with a boring bar to restore design specifications.

These complex and intricate steps were accomplished in minimal time thanks to the skilled experts at our St. Louis Turbine-Generator Repair facility. Our customer’s turbine was back in use with a short downtime and running again at optimum efficiency.

Have MD&A look at your turbine rotor today! Call our Turbine-Generator Repair Facility at (314) 880-3000 or use our Contact form.

The post Bucket and Thrust Collar Replacement appeared first on MDA Turbines.

In-place stationary shaft machining allows MD&A to repair damaged journals, collector rings, and seal areas without removing turbine and generator rotors from the unit. The compact setup easily fits under LP hood radii to allow for machining along the complete rotor train.

Saving you time and money, this capability eliminates unnecessary downtime. Advantages include:

Cost Effective:

• Reduction in crew size, as disassembly is limited to removal of outer bearing cover and Babbitt bearing.
• Shorter schedule duration.

Lay down area reduction:

• Portable lathes occupy valuable space on a turbine deck, whereas stationary journal equipment requires only three standard gang boxes.
• Repairs can be performed with the rotor left in the unit.

Time Constraints:

• Most stationary journal repairs can be completed in three to four shifts, start-to-finish.
• Reduces schedule impact by eliminating disassembly & reassembly of the steam turbine.

Our technicians have 20+ years of experience with in-place stationary shaft repairs.

MD&A experts first perform a complete Foreign Material Exclusion (FME) of the bearing standard to ensure metal shavings do not enter the lube oil system and the packing gland is sealed to prevent intrusion of foreign contaminants.

Diametrical measurement inspections and concentricity sweeps are then completed, and findings are discussed with the customer prior to machining.

Next, the honing and polishing process is performed – surface finishes up to 2Ra are achievable. The concentricity of the journal is checked throughout honing process to maintain centerline.

The machining process allows for a perfect blend of newly machined diameter to the existing radius.

We also offer Babbitt bearing restoration in our facility upon completion of shaft machining, to accommodate for the new diameter.

MD&A can currently accommodate shaft diameters from 9 – 24 inches with additional sizes supported when the schedule allows. This new service increases our ability to respond quickly to our customers’ ever-changing needs.

MD&A continues to invest in new capabilities that enable us to expand our quality service and repair offerings. 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.

For additional information, call MD&A’s Turbine-Generator Repair Facility today at (314) 880-3000 or use our Contact form.

The post In-Place Stationary Shaft Machining Capabilities appeared first on MDA Turbines.

The horizontal bore machine, shown in the video below, is just the latest example of how MD&A ensures that you get the best people, the best equipment, and the best service available anywhere.

For additional information call MD&A’s Bearings, Seals & Hydraulics Division today at (440) 946-0082 or use our Contact form.

We remain committed to being the power industry’s trusted partner for refurbishing and manufacturing high-quality turbine bearings. Our experts are continually looking at ways to broaden our capabilities so you can maximize uptime. It’s how we retain our leadership position in the industry and our reputation for great products and top-notch customer service.

The post Investing in Journal Bearing Ball Ring Repairs appeared first on MDA Turbines.