The inconsistency in machinery controls created operation and maintenance inefficiencies at two Boeing plants in the state of Washington. With a control system upgrade, they were able to make the aging machines work like new — or possibly better — at a fraction of the cost of purchasing new machines.
The shot peener machines in Boeing’s Auburn and Frederickson plants were between 20 and 40 years old, and based on different, aging control technologies and hardware. Some machines used hardwired relay logic, while others had older Programmable Logic Controls (PLCs) and Computer Numerical Controls (CNCs). The inconsistency in machinery controls created operation and maintenance inefficiencies. Parts were becoming obsolete, and maintenance was becoming more expensive. Reliability was an issue. Managers knew that an upgrade was in order.
The aging equipment in question, seven shot peener machines, is used to form and contour the wings and also to harden the wing surfaces of 737, 777, and 767 aircraft. The process involves blasting the aluminum part at high speed with metal shot of different sizes depending on the operation. Larger shot diameters (as large as 0.54 inch) are used for forming and smaller diameters (as small as .028 inch) are used for cold working (i.e., surface hardening). The specialized shot peener machines are quite sizable. The Spanwise Peener machine is 3 1/2 stories high — large enough to fit the wing skin of a 747 aircraft. Continue Reading →