February 24, 2014

The Lean Transformation in Pratt and Whitney - 1991 - 1995

Mark Coran, UTC Controller got a new assignment on 1 June 1991, to manage the costs of Pratt and Whitney, UTC's largest subsidiary and builder of aircraft engines.

After discussions, it was decided to implement lean principles in physical production first.

Coran announced that every product would be made in continuous flow to the maximum extent possible with a cost reduction target of 35% in constant dollar terms in four years and lead time reduction target of four months.  He brought in a lean thinker from UTC Headquarters, Bob D'Amore.  Despite initial attempts things did not move as expected.  In the mean time George David moved up to become President of Untied Technologies and was introduced to lean thinking by Ary Byrne. He visited Wiremold and saw Shingijutsu consultants working on the shop floor and coming up with improvement suggestions. When Mark Coran reported his status of the project to David, he immediately suggested to him to employ Shingijutsu consultants. But they came to know that GE's Aircraft Engine Group is planning to engage them. But David made an emergency appointment with them and got into a multiyear agreement.

Chihiro Nakao, a Shingijutsu consultant visited the factory in May 1992.  In the space of a week, he demonstrated many improvements in the Pratt's Middletown, Connecticut plant. Also, Karl Krapek, an industrial engineering degree holder from Purdue and who also completed General Motors' IE program was deputed as President of Pratt and Whitney.

Krapek tried to implement JIT in General Motors, but got into problems and them moved to Otis Elevator. From there, he moved to Carrier where he was implementing lean with the help of Shingijutsu. He came to Pratt, and grouped the two thousand parts of in a jet engine into seven product categories - rotors and shafts, turbine airfoils, combustors and cases, nacelles, forged compressor airfoils, compressor stator assemblies and general machines parts. Each product category was housed in a plant with the eighth plant being final assembly.

The fall in demand of Pratt at this point in time demanded head count reduction. Lean transformation required the concepts of multiskilling and mutli machine operations, job rotation, and continuous shuffling work groups to accommodate varying volumes of different varieties of engines. After protracted negotiations between the International Association of Machinist, George David and Karl Krapek, and the State of Connecticut, an agreement was reached in the spring of 1993 to reduce manpower to 29,000 from 53,000 in 1991.

The two basic activities of P&W are fabrication of parts from castings or forgings and assembling them into engines.

Turbine Blade Manufacturing Division

In 1991, 1,350 employees used 600 machines to manufacture #1 billion worth of turbine blades and guide vanes.   Ed Northern organized the plant in 1993 into flow lines and also made it possible to reconfigure them as needed. With the modification in the next two years, overdue parts fell to zero, inventory was cut in half, manufacturing cost was reduced by 50% in many cases, and labor productivity doubled.

Redesign of a Monument in Turbine Blade Manufacturing Division

Womack and Jones say a monument in lean thinking is any machine which is too big to be moved and whose scale requires operation in a batch mode. In the case of this North Haven turbine blade unit it is a massive $80 million complex of Hauni-Blohm blade grinding centers.

The redesing involved $1.7 million per cell and it reduced throughput time to 175 minutes from the earlier 10 days. The grinding cost per blade was also brought down to 50%.

The Final Assembly Plant

Bob Weiner was appointed a head of final assembly in july 1984.  The engine was placed on a moving track. Yuzuro Ito  was asked to help in the quality area.

Pratt's lean transformation did turn around the plant from problems.

Operating results improved from losses in 1992 and 93 to profits in 94 and 95.


Lean Thinking
Jim Womack and Dan Jones
Simon and Schuster, 2003

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