Building a Machine Foundation
Monday, September 28th, 2009
The precision begins from the ground up!
Over the years, The Gear Works has developed a technique to construct large stable concrete foundations to support its many heavy machine tools. The proper installation of a rigid foundation is essential in this era of modern CNC machine tools which are assembled with modular components and connected only by electronic cables – and the base on which they sit. It is the foundation that supports and maintains the position of the machine modules, and provides a barrier against external floor vibrations. This is especially critical with gear manufacturing equipment, such as our new Gleason-Pfauter P800G gear grinding machine, where stability of the grinding head stanchion, work table and tailstock modules must be precisely maintained to assure DIN 1 gear accuracies. To complicate matters, the Gear Works facility is located in an area of soft alluvial glacial soil where heavy machines tend to settle unless properly supported.
The Foundation begins with the excavation of a large pit, approximately 12′ X 24′ X 8′ deep. The bottom of the pit is backfilled with 18” of compressed sand capped with an 18” reinforced concrete floor. A wooden form is then constructed to cast 16” thick concrete walls. After the forms are removed, the result is a sunken tub that is flush with the shop floor.
After the concrete walls have cured, the inside of the shell is lined with a special vibration absorbing mat. Rebar is suspended into the pit along with block-outs to form tie-down anchor pockets.
Over 16 yards of 4000 PSI rated concrete is pumped into the cavity. The mix is thoroughly agitated with a vibrating probe to prevent voids.
After one month of curing, the foundation surface is painted with a concrete sealant. The new machine now has a proper base on which to sit.
* 51 total yards of concrete
* 500 feet of reinforcing steel
* 32 Tons total foundation weight
* 24 Tons total machine weight (Pfauter P800G)
* 11 Tons maximum work piece weight
At The Gear Works, our commitment to excellence starts where the sun doesn’t shine!