CEB Press 6 - Overall Machine - Calculations

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Engineering Analysis

Scott Eisele - We have made arrangements with Marcin to bring one of the CEB presses here to Vanderbilt University. The plan is to fully instrument the machine so that we can run experiments on it and create simulation models that allow for data-guided development. The data will be made available.

I am looking for suggestions with regard to the experiments that this group would like to have run on the machine since this will help determine what instrumentation we need as well as other components we should purchase.

We anticipate experimenting with:

  • alternate power source (electric motor, PTO)
  • identifying why the machine has not been able to run at full speed (cause of pressure spikes)
  • Rate of wear on the machine
  • running a smaller power source for the majority of the duty cycle with some energy storage(flywheel) to assist during final high pressure compression
  • an-isotropic properties of the bricks
  • alternate control logic (pwm of solenoid, sensors used for control of motion)
  • FEA
  • Pressure Profiles
  • Hydraulics circuit layout alternatives

If you have suggestions for experiments please share them.

Brick Pressing Rate

Theoretical Brick pressing rate calculations and data validation - as a function of:

  • hydraulic fluid flow
  • compression pressure (varied from 2000 to 2500 psi)
  • brick thickness (from 2 to 4 inches)
  • Soil shaker usage - for example, with optimized soil preparation (no shaker usage required because soil never bridges)
  • different secondary cylinder bore sizes (current is 2.5"x14" stroke, 1.25" rod) - we may need to use 3" bore to slow the cylinder down
  • Cylinder rod size (for example, using a larger rod on the main cylinder will increase the retraction speed of the primary cylinder - increasing brick pressing rate for the same power usage)
  • Maximum drawer speed determination prior to mechanical failure of the secondary cylinder (too much stress from moving fast and stopping abruptly)
  • Optimization of pressing rate for engine horsepower - for example based on selecting a lower pressure pump with higher flow, or potentially, a 2 stage hydraulic pump

R Values of CEB Walls

  • For walls. R=20 for 6 inches of blown cellulose insulation, + .3/inch ([1]) for 12" of brick, so about R=4 for brick.


  • R=0.3/inch - AECT - [2]
  • R=1/inch of unstabilized CEB - [3]