One of the forces that act on a pig while in operation in a pipeline is that due to the layer of wax deposited on the pipeline wall. Therefore, if the motion of a pig or its cleaning efficiency are to be determined this resistive force must be known as a function of the relevant parameters. The goal of this paper is to present a procedure for evaluating this force in situations of engineering interest. In essence, the procedure consists of the following steps: (i) determine the war shear strength according to an experimental procedure developed for this purpose; (ii)from finite-element results, obtain the maximum stress in wax; (iii) with the foregoing information, calculate the pressure required for the pig to cause a maximum stress on wax equal to its shear strength. This pressure value is the threshold below which no wax removal can occur; according to the present simple approach. in this paper; each of these steps is described in detail and exemplified.