Case Studies

Evaluation of 750 Gallon Aaron Process Split Level Mixer

Client was moving operations from PA to a new facility in IL.  A vintage process mixer illustrated considerable wear and was to be placed out of commission for the purchase of a new machine. Orbis Machinery, LLC and Weldall Mfg. collaborated in the evaluation process of the mixer and determined the existing unit was repairable. The scope of work developed as such:

Phase 1, Timeline: 2 Weeks, Scope of work: Disassembly

  • Sandblast, disassemble, clean and inspect all mixer components
  • Hydrostatic test and thickness measurement of jacket and bowl
  • Clean discharge valve assembly.
  • Motor inspection and no load test run.
  • Document and provide Client with detailed inspection report.

After determination was made that the mixer could in fact be rebuilt. Client moved forward with the order to commence the project.

Phase 2 (Mixer Assembly), Timeline: 5 Weeks to complete, Scope of work: Reconditioning & Assembly

  • Fabricate new cover assembly for mixer
  • Recondition both blades.  
    • Dye Penetrant test blade hubs
    • Resurface shaft seal areas (packing)-weld buildup
    • Check Run-Out of each blade
    • Build up blade tips as needed
    • Flame spray and build up worn areas of shafts. Machine back to tolerance.
    • Machine new keyways in shafts and supply new keys
    • Spur gears have uneven wear on work face of teeth. Tooth profile still at 90%. Install gearing with faces rotated and opposite side of tooth being used.
  • Repair and grind radial surfaces of bowl.
  • Paint all usable mixer components with Sherwin Williams Pure White 2 part epoxy.
  • Motor to be completely rebuilt and rewound with heavier class insulation. 2 year warranty provided.
  • Assemble Mixer
  • Repack gland housings
  • Replace Motor Sprocket and bushing
  • Replace Gearbox Sprocket and bushing
  • Replace Drive Belt
  • Replace Drive Coupling
  • Replace Intermediate (outboard) support bearing NOTE: Pillow block housing to be reused
  • Replace (2) drive end support bearings NOTE: Pillow block housings to be reused
  • Replace (2) idle end support bearings NOTE: Pillow block housings to be reused
  • Replace Gear case flange bearing
  • Replace Gear case seals
  • Provide all new fasteners
  • No load test run of assembled unit.
  • Mount new cover and safety grates. Add swing bolts and hold down tabs.
  • Load mixer on truck for shipping

Final Outcome: Client saves 70% of the cost of a new mixer. Total turnaround time 6 weeks versus 26 plus weeks for delivery of a new mixer.