Saga of the first GE LM2500 powering a BRUSH ac generator – III

February 22, 2017

By Ivan G Rice

Article

This is the third and final part of this series. Part 1 and Part 2 can be read here.

Final Selection

After much playing the game (collecting hints of final selection), I was in Stavanger and it was suggested we to get to London the following day as P&W seemed to be prevailing. In that meeting with Mathew-Hall and Mobil there were only two of us, myself and Len Green. The question was “Where is your legal team?” Our response was that we did not require one. This was real surprise as P&W brought a huge delegation of legal council. Needless to say, the negotiations proceeded smoothly to the delight of the Mobil team and the rest is history. A long time later, discussions with Ivan Rice (GT Consultant) revealed the extent of rivalries within the consortium.

C-W Power Systems agreed to satisfy most participating countries with equipment and construction work assigned, where possible, to USA, Norway, UK, and Holland. This was accomplished by requiring additional logistics and overall project management. The work was completed and the Platform Modules were delivered on large barges and towed to the Statfjord platform to be hoisted by a huge sea-going, self-propelled crane named ‘Sea Troll’ operating out of Stavanger, Norway.

The Sep Post Script

C-W was not successful with the next phase of the Statfjord North Sea development. We pioneered the way with innovation and creativity which others benefited from and copied. BRUSH became a major supplier of generators for the LM2500 series of gas turbines and the subsequent upgrades with increased ratings. That is a most pleasant memory and contribution of the 70’s as well as the many friends made at BRUSH.”

Now back to my part of the saga. Septimus told me that he had been to the top of the three very high legs before the top deck was in place. He was elevated there by a rack and pinion open frame cage and at the top all that was around the each leg was some wooden tomato crates to keep him from falling over board. This must have been eerie and scary for him. He also told me that he was on the finished platform to inspect the 6 LM2500 units. He flew to Statfjord A on a helicopter from Stavanger and had to wear protective suit in case of a forced down to help protect him from the icy cold waters. Sep followed the whole job from inception, to bidding, to design. to fabricating, to assembly, to testing and to the installation on the platform. He deserves a lot of credit for all the hard work he did in pioneering a game changing new way to power the large platforms. What a success Statfjord A has been.

Post Order Engineering

After the two orders for the GE LM2500 packages were placed on Curtiss-Wright there remained a large number of details that required engineering attention. I continued as Mobil's gas turbine consultant to take care of many of these item for a period of time until the first of October of 1976. At times I was not needed and could stay home in Spring, Texas with my family and carry forward other consulting work for other companies which I did. However, the main need of my services involved the selection of the gas turbines and packages. I also helped get the gas turbines on Beryl A ready to run and spent 10 days on and off the platform supervising the final installation details until October 18.

After the orders were placed there were several things that needed attention right away such as the inlet air ducting, the air filtration system, the couplings, the controls, the design of the enclosures so that the gas turbines could be easily and quickly remove to mention a few. All of the Curtiss-Wright drawings had to be carefully reviewed and closely checked. On September 16 I wrote a 3 page letter at Mobil's request outlining 27 rotating equipment items remaining to be monitored and supervised. I still have a copy of this letter in my files.

I wanted Mobil to incorporate a fourth stage of inlet air filtration to better protect the LM2500 units. This proved to be costly and it took a lot of effort to get Mobil to finally order this extra filtration. Bob Bolfing of Mobil Houston and I even visited the US Navy testing facilities in Philadelphia to get their input to use. We were able to read restricted reports through Gene Weinert but not copy them. The US Navy helped us a lot with the LM2500s. We were determined to make the LM 2500s a success.

There was one area where I spent a reasonable amount of time and that was in regard to the engineering details needed after Statoil, through Mathew Hall, ordered 3 Kongsberg 1500 KW small auxiliary gas turbine generator sets for the platform. About 4 to 5 MW of power was needed before there was any wells drilled and when the drilling took place and there was no fuel gas or crude to pump I had recommended ordering three 2500 KW 501K Allison generator sets, but was over ruled by Statoil because they wanted as much Norwegian content as possible. The 3 units ordered were too small and without any off shore experience. After the order was placed I was asked to follow up on many details by working directly the Jan Movil, President of the Norwegian Kongsberg company.

Ihad already placed on order 3 Allison units through Mathew Hall and Jim Struthers of Allison and this order had to be canceled. The Kongsberg units proved to be too small and unreliable when placed in service which caused trouble when Mobil had to run one of the LM 2500s continuously at 4 MW as will be explained in the post script. There were many details to attend to on the Kongsberg units such as the inlet filtration, the duct work, the duel fuel capability, the controls, etc which was my job to sort out through Jon. Together we put the units in shape the best we could.

Mobil Oil told me not to make a fuss of this wrong decision because Stat Oil was still upset that the 6 LM2500s were ordered instead of the T P & M GG 4s. I was told by Bob that I got what I wanted with the GE LM2500 orders and not to up set the apple cart and not open up a can of worms. T P & M was still trying to reverse the LM 2500 order. There was nothing I could do but drop the issue. I was asked to witness the testing of 5 of the 6 LM2500 gas turbines at GE's plant in Evendale,Ohio which I did. All of the units passed with flying colors. I also made several trips to the Curtiss Wright plant in Woodridge, New Jersey to handle details and communicate with the various Mobil and Mathew Hall engineers.

I worked hard for Mobil and Statoil and I got along very well with the ones I directly worked under. They treated me with respect and as a full time employee with all the privileges they had. They gave me a lot of authority which I exercised as needed from time to time. I became good friends with many of them and remained so for a number of years. I enjoyed working for all of them. Together, we made a great contribution for large platforms through the use of the LM2500. We opened up a new market for the BRUSH electric generator.

Post Script

There are several items that are not necessarily part of the above story that might be of interest to the readers. I will mention some of them as follows:

true indicator of the out come of the Statfjord A game changer, as manifested through the aero gas turbines and BRUSH generators, is the large number of BRUSH generator orders obtained as of the end of 2014 given below from all packagers. Also listed on the right is a breakdown of the GE aero gas turbines Statoil has ordered to date.

BRUSH Generator Orders Statoil GE Aero Engine Fleet

544 LM2500 units and variants 5 LM1600 uinits

59 LM5000 units 123 LM2500, PGT25 and PGT 25+ units

698 LM 6000 units 10 LM6000 units

59 LMS 100 units ____

1360 Total 138 Total

Recently, GE announced that it has received 10 more orders for the LMS 100s, 5 at the 100 MW rating and 5 at the new plus 118 MW output, to back up the growing southwest US solar and wind power, all to be equipped with BRUSH generators. The above list for the BRUSH generator orders shows that GE aero continues to use the BRUSH generators for their generator packages. Engineer Jim Prochaska of Houston GE Power and Water recently told me that the BRUSH generator design, with the modern endframe bearing mounting, fits their packages better than the GE design, is competitively priced, and that BRUSH gives them very good engineering support, on time delivery, installation support and after market back up and that GE Power and Water- Aero is well pleased doing business with BRUSH.

The technical report I and Erichen wrote was well received and the partners found out about it and wanted a copy to use. Aramco asked for a free copy. Mobil management (Clifford Case) offered to sell it to them for $35,000 US dollars, but Aramco thought this was too much money. Several years later when I was consulting for Aramco I found out that Aramco had gotten a copy of the report through T P & M for free. Evidently either Statoil, Mathew Hall or some one in Mobil had boot legged a copy to T P & M trying to get them to poke holes in the report to get the order reversed. Later on Mobil Oil gave each partner a copy free.
Statfjord A is a World famous platform and has been a huge crude oil producer and most successful no doubt to a great extent because of the GE LM2500 gas turbines as well as the Elliot compressors and the BRUSH electric generators. The web has a number of interesting articles and photos of this platform. By the year 1998 some of the LM2500s had run over 100,000 hours without being replaced according to an article by GE. Today the run times are no doubt much higher. The platform was overhauled by Statoil a few years ago and is now expected to keep on producing crude until the year 2020 to give over 40 years of production. My reports used data by Mobil oil that predicted, starting in 1980, no more than 20 total years of production and full production for only 8 when production was to start dropping off rapidly for 12 years.
As the design of the top deck continued the weight kept going up where a point had been reached early in 1975 when it became necessary for Aker to re design the tops of the three concrete legs to hold this ever growing weight. 50,000 tons was a lot of weight to carry. This re design was done, but it delayed tow out a full year because there was only a 3 month window of opportunity that was safe to tow the giant completed platform to its designated location. This extra time was well used and did not overly rush us in the design of the platform. However it delayed income from the crude for a year. Weight became critical and the lighter weight of the aero engines proved to be an advantage. Mobil was glad they had selected the light weight LM2500s.

5 . When the LM2500s were first placed in service one unit had to be run at about 20 % load continuously to supply power for the drilling part of the platform. The small 1500 KW Kongsberg units were too small and not reliable. Under this light load condition the first stage compressor bladed developed a problem. These blades had dampening struts about 2/3rds of the way out that locked together at about 70 % speed, but at lower speeds the surfaces would rub and excessive wear took place. GE had to replaced these blades with struts having much harder surfaces to withstand the rub. This correction was costly to both GE and Mobil. The LM2500s ran fine otherwise.

The Phillips Petroleum Company in London was very helpful to me and Mobil. I knew Harry Doyle from Bartlesville GE days originally and ran into him in London. We met a number of times and he gave me valuable operating information and tips as he was head of the engineering for the very large Ekofisk platform located in the English part of the North Sea. He helped me stiffen the speed increasing gear box for the Mobil Beryl A compressor train as they had to replace the gears every 5000 hours because the movement of the platform would twist the gear casing back and forth causing the gears to wear badly. I filled the Clark 24 inch base under the gear box with non shrinking concrete.
Liklewise, the US Navy with the help of Gene Weinert, hept us out considerably sharing with us the operating and maintenance experience they had with the GE LM2500s, especially regarding the inlet air filtration on the open sea.
Late in 1975 Mobil was planning two more platforms for the giant Statfjord field (Phases II and III), Statfjord B and Statfjord C. John Manning in charge of the planning respected my views as an engineer and asked me to write a report for him on using 4 legs instead of 3 which I did. The top side weight had risen to 50,000 tons and was stressing the 3 leg support. Four legs would give better weight support and provide 3 legs for drilling, but it would cost a lot more to make. Also 4 legs would be more stable. In the end, Mobil elected to use 4 legs for B and C. Brown and Root did the engineering for B and probably also for C. Top side designs of B and C were pretty much duplicates of A and used the 6 gas turbine arrangement as for A. Platform B was placed a short distance to the south of A and C a short distance to the north. Top production of the three was over 850,000 barrel of crude a day, with A being the leader at 320,000. Statfjord A remains King of the three to this day and is still producing and will do so until the year 2020.
Mobil Oil was very good to me and let me use their new satellite phone after hours in the evenings to carry forward my ASME work and to phone my wife. The 5 hour time difference made it possible for me to phone the US after 6 PM London time and get the US at about a 1 PM. This was a big help to me. I could dictate letters to my wife, Carolyn, for her to type and send out to committee members and staff. As a point of interest, during 1975 I was asked to become Region X ASME Vice President which would have been a stepping stone to the presidency. However, Carolyn and I were too tightly strung out with work and we had to turn the job down. It would have been time consuming and costly to us involving trips to each ASME section in the region and trips to national ASME meetings.
The Mobil Oil president in one of his meetings gave praise to me and Arne for the fine report we had produced for Mobil and the contribution we had made according to what I was told by Bob Bolfing.
Mobil, with my consulting job in London, made it possible for Carolyn and me to visit a several European countries and places during the two summers we were in London that otherwise we could not have done ((Wales, Scotland, Ireland, Norway, France (Paris), Germany (Berlin), Poland (Warsaw) and Russia (Moscow, St Petersberg and Kiev)).