Whirlpool Corp. faces myriad business risks and uncertainties in its $18 billion global appliance business, but its legal bills from midsize Michigan law firm Warner Norcross & Judd aren’t one of those unknown variables.

That’s because Whirlpool tapped Warner Norcross as its North American business litigation firm this fall, with plans of setting up flat-fee billing for court fights and related tasks such as creating bulletproof contracts for Whirlpool.