Method of controlling lance movement through heater exchanger assemblies

A computer program product including at least one non-transitory machine-readable medium encoded with instructions that when executed by one or more processors cause a process for a motor to feed a lance into a tube in a heat exchanger at a variable feed rate dependent on temperatures of different portions of the tube, the instructions comprising:

• receive identified hotter regions and cooler regions within an internal volume of the heat exchanger, wherein there is more fouling on an inner surface of the tube in the hotter regions and less fouling on the inner surface of the tube in the cooler regions;
• generate the variable feed rate of the lance based on the hotter regions and the cooler regions, wherein the variable feed rate is slower in the hotter regions and faster in the cooler regions;
• feed the lance into the tube at the variable feed rate;
• and
• dispense a cleaning fluid from a nozzle on the lance toward an inner surface of the tube as the lance is fed at the variable feed rate, wherein the cleaning fluid contacts the inner surface of the tube to clean the fouling therefrom.