Grinding is an ultra-precision machining technology. The grinding force and grinding heat emerge as pivotal physical parameters. Excessive grinding temperature can engender unwarranted thermal damage to the processed material. In cup grinding wheel face grinding, employing a singular abrasive grain discrete heat source method enables a more precise establishment of the face grinding temperature field. Cross tracks of abrasive exist widely in cup grinding wheel, and the influence of cross point temperature should be considered in order to accurately establish the grinding temperature field model. Thus, a single-grain discrete point heat source superposition temperature field analytical model was established. Through trochoid feed scratch experiments, the variation law of thermal effect of cross points under different cutting depth is verified. The experimental findings reveal conspicuous changes in cutting force and cutting heat at the entry and exit positions of the scratch intersection region. Moreover, the abrasive grain scratch sustains more severe damage compared to other regions. The energy change caused by the impact effect is the key factor leading to the temperature change at the intersection. The energy lost at the entrance of the intersection position is close to the energy of the impact effect. With the increase of the cutting depth, the ratio of the two tends to converge towards 1, ranging from 0.868 to 0.932 to 0.965. The error between the theoretical model and experimental verification is less than 5%, indicating the single-particle discrete heat source superposition temperature field model can well characterize the grinding surface temperature field caused by crosspoint effect, which lays a foundation for the grinding heat theory based on trochoid model.