Stud Hole Repair/Restoration

We were recently contracted by an industrial customer in the Midwest to repair stud holes on a piece of equipment at their facility.  This is a common repair we perform, and is executed utilizing our specialty equipment and skilled technicians.  The photos below will show the mill that is mounted to the face of the surface that will have the stud hole repaired.  The hole is bored and tapped, and a threaded insert is installed.  Great work by our team!

Allis-Chalmers Industrial Steam Turbine Major Inspection

Power Services Group (PSG) was contracted by an industrial customer in the Midwest U.S. to perform a major inspection of their Allis-Chalmers steam turbine generator.
This unit is a non-condensing steam turbine that is directly coupled to an Allis-Chalmers air cooled generator. The turbine and generator set are of a three-bearing
design.

During the project, a Safety Meeting was held prior to the start of any work. The Safety Meeting topics were based on work activities to be performed during the shift. In addition, hazardous observations which could impact the safety of the team were discussed and resolved. Prior to performing work, a Job Safety Analysis (JSA) form was completed by the work team. This project had no accidents and no first aid incidents.

The steam path components, once removed, were dust blasted and received nondestructive examination (NDE). The NDE revealed minor indications on the stationary blading, and no repairs were deemed necessary at this time. The turbine rotor and stationary stage 6 were shipped to our steam path component inspection and repair facility in Pevely, Missouri for replacement of the 7, 8, 9 and 10 rotating blades, and repairs to the #6 stationary stage.

The generator field was removed from the stator and both the generator field and generator stator, received visual inspections and electrical testing. The generator field was shipped out to receive a retaining rings-off inspection. The stator was ice blast cleaned, received a re-wedge of the stator core windings, and final coated with an insulating epoxy.  The journal bearings were removed and visually and dimensionally inspected and received dye-penetrant and ultrasonic testing. Inspections revealed that all of the bearings, new and in service, were in excellent condition. The pedestal oil deflectors were removed and visually and dimensionally inspected. All were found to be beyond industry standard clearance tolerances and were replaced.

The inlet control and extraction control valve racks were removed, cleaned and visually and dimensionally inspected. The valve poppets and seats were NDE inspected and found to be in very good condition and were returned to service. Some of the valve linkage bushings and pins were found to be worn and were replaced. The trip throttle valve (TTV) and operator were removed, disassembled, cleaned, and inspected. All inspections were approved and the components were returned to service. The lube oil cooler was removed and replaced by plant personnel. The lube oil system shaft driven main and steam driven auxiliary oil pumps were removed and received inspections. The main oil pump (MOP) and the steam driven auxiliary oil pump, (AOP) were found to be in good condition and were reassembled and returned to service. The lube oil reservoir was opened by PSG and initially cleaned by plant personnel. Some sediment and sludge were found during the initial cleaning of the lube oil main reservoir. PSG performed a final vacuum and hand cleaning of the interior of the reservoir prior to the lube oil system high velocity oil flush (HVOF). A lube oil system HVOF was performed utilizing an external pump and heating/filtering skid. The flush was ran for approximately 72 hours and was completed once system cleanliness was acceptable.

The system trip devices were inspected, cleaned and flushed; all linkages were checked for wear and proper freedom of movement. The mechanical over speed trip test was completed after initial startup and the unit was later tied on-line. PSG personnel demobilized the job site and were released to travel after another successful project startup.

Zero safety incidents, quality work, Nice job team!

Boiler Feed Pump Barrel Repairs

We were recently hired to remove a small indication around the radius of a Boiler Feed Pump Barrel.  We mobilized our experienced technicians and specialty equipment to site.   Once we evaluated the indication, we built a 6″ boring bar to machine an undercut in the radius of the intermediate face and the barrel bore to remove the indication.  A dye penetrant test was performed to ensure satisfactory results.   The customer was satisfied with the end result, and we were released from site.  Another quality job with zero safety incidents and a satisfied customer!

Chemical and Petrochemical Customers

Power Services Group (PSG) is a preferred turbine services provider to the chemical and petrochemical industry.  Our Project Team structure – consisting of Technical Field Advisors, Foreman, Project Coordinators, and Turbine Mechanics – keeps the team members working together as regularly as possible.  The familiarity of our safety and quality processes and procedures by all members of our project team make PSG an ideal supplier for turbine maintenance projects at any chemical facility.  We specialize in the type and size range of most gas and steam turbines found within these facilities, and know what it takes to get the job done on-schedule and on-budget, all while following strict safety guidelines throughout the project.  If you have any upcoming turbine maintenance needs during your next turnaround please contact us today to learn more about how we can be of service to you.

Turnkey Turbine Outages

With over 34 years of experience performing turbine generator maintenance and repair services, PSG knows what customers expect when it comes to managing an outage.

Above and Beyond

A PSG inspection is more than open, clean and close.  Our quote includes all of the work implicit to your Statement of Work to achieve a comprehensive inspection – minimizing Change Order surprises.  We examine every relevant aspect of the power train.  We perform meaningful measurements of components and clearances and record multiple measurements at each location.  Recording this extra data allows us to better identify potential problems and enables us to establish trends across successive inspections.

We have the right resources and the right people to provide professional and total turnkey outage service. That is, PSG will procure and manage all resources needed to complete your outage, and you can rest assured that our outage scope will be taken care of professionally and efficiently.

When you choose PSG for your turbine generator services, we immediately begin strategizing for your outage with our experienced project teams, our project-specific planning, our learned and tested processes, our customized tooling, and our attitude of safety and customer service.

  • Planning: PSG can help you plan for your next outage through the development of the workscope, parts requirements, tool inventory and recommendations, and bid documents.
  • Communication: We understand how important communication is and tend to over-communicate through daily status reports and daily project meetings.
  • Quality: PSG is so confident in our quality that we can offer a one year warranty of our work, including our PSG contracted suppliers.  This means that if you suspect a deficiency in our work on your outage, we will immediately come out to investigate.  If we find that the problem is our responsibility, we will immediately mobilize all resources necessary to correct the problem, at no cost to you.

If we find damage or deviation to specification, we perform a full assessment to diagnose the root causes behind the symptom and recommend actions to prevent its return.  These recommendations may include operational or maintenance changes.  The goal of our comprehensive measurements and proactive approach to repairs is the elimination of future forced outages.

Trust PSG and our experience in serving any of your power generation needs. Contact us today for more information.

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.

On-Site Turbine Repair Services

If it is beneficial to you to have turbine component repairs performed on-site, we offer our portable equipment to be ready when components are removed from the turbine.  Contact us today to reserve our portable repair equipment to be on-site for your next turbine outage.

Wind Turbine Machining

We recently completed another uptower wind turbine shaft machining project.  Our equipment and personnel will travel to wherever the problem may be.  For the wind industry, it happens to be 200+ feet above the ground, but we’re happy to do this on your turbine deck or any other area in the plant as well.  Please give us a call if you have any emergent shaft machining needs, we’ll respond quickly and get your equipment back up and running.  For more information on our wind turbine specialty machining services please CLICK HERE.

 

Before

 

After

3D Component Scanning

It’s that time of year again!  When turbines are running throughout the summer season it’s a good time to scan any common parts that you may need to order again in the future.  With our portable metrology-grade 3D scanning equipment, we are able to scan components within extreme accuracy.  You can ship your components to our shop, or we can bring the experienced technicians and scanning equipment to your facility and analyze the components right there at your site.  If you have any component engineering needs please give us a call.  We’d love the opportunity to help in any way we can.   CLICK HERE for our phone and email contact information.

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!