Carborundum manufactured abrasive powder used in the manufacture of steel.  It contracted with Lake River to bag and warehouse the powder for Carborundum and to ship the bagged powder to Carborundum customers.  As part of the deal, Lake-River acquired new equipment.  The contract included the following clause:  

In consideration of the special equipment to be acquired and furnished by LAKE-RIVER for handling the product, CARBORUNDUM shall, during the initial three-year term of this Agreement, ship to LAKE-RIVER for bagging a minimum quantity of [22,500  tons]. If, at the end of the three-year term, this minimum quantity shall not have been shipped, LAKE-RIVER shall invoice CARBORUNDUM at the then prevailing rates for the difference between the quantity bagged and the minimum guaranteed.

      Do you see how this amounts to a liquidated damages clause?  Applying rules concerning the validity of liquidated damages clauses, the court found the clause invalid.