Single-piece flow the way to go

When we started the Combustion Shop at Savannah Machinery Works’ in the fall of 2010, it was vital for us to quickly make changes to machining processes because we were still learning how to make combustion components. We were reacting to tight development schedules and flexibility was critical to producing components quickly and efficiently.

As we enter our third year, the development schedule has slowed and we are settling into a more stable production rhythm. As a result, we are trying to make our processes leaner and to use capital and human resources more efficiently. Demand dictates we build one combustion unit per day. However, we expect demand to steadily increase over the next few years, requiring a corresponding increase in output.

All images courtesy C. Tate

Savannah Machinery Works can produce a fixture, such as this large tombstone with a vise that has a set of machined jaws, in a few hours to solve a machining problem.

We manufacture several different combustor configurations, all in sets of 16.

Combustion assemblies can require hundreds of man-hours to complete, so it is absolutely necessary to have a steady flow of components moving through the manufacturing process.

Combustion components are constructed by machining welded assemblies and subassemblies. In many cases these parts go through a series of welding and machining operations. Welding can take hours, typically several times longer than cycle times for the machining processes, and many assemblies require multiple machining operations.

To maintain a steady flow of product through the processes, we will need to machine components one at a time rather than in complete sets of 16. The lean term for this is “single-piece flow.” It requires efficiently switching from one component to the next with minimal setup time, and is essential to meeting production schedules and keeping machining costs in check.

A chuck and a quickly made fixture on a vertical machining center demonstrate Savannah Machinery Works’ flexibility.