<p>In recent decades, industrial robots have emerged as pivotal contributors to the global manufacturing landscape, revolutionizing various sectors through increased automation and efficiency. Simultaneously, the application of heavy-duty robots in heavy industries is gradually increasing. In this study, a self-developed heavy-duty robot is utilized for automated fiber placement (AFP), with a one-ton layup system integrated at its end effector. To fully leverage the robot’s performance and ensure the precision and efficiency of AFP, particular attention is given to the dynamic performance of the robot. The heavy-duty robot is equipped with a hydraulic equilibrium system (HES) to alleviate gravitational loads on the joint motors. However, the introduction of the HES increases the complexity of the robot’s dynamics. In this paper, the HES is modeled using a Maxwell model based on thermodynamic analysis, and its parameters are identified using the CARMA model. The robot’s drive mechanism is then analyzed. Subsequently, an overall dynamic model of the robot is developed, along with a hybrid friction model. An incremental identification strategy for dynamic parameters is proposed, which involves sequentially identifying the friction parameters, gravitational parameters, HES dynamic parameters, and the remaining inertial parameters of the robot. Experimental results show that the proposed dynamic model accurately predicts joint torques, with the HES dynamic model demonstrating smaller residuals and faster response times compared to the comparison model. Besides, a preliminary analysis and optimization of the dynamic inconsistency between the HES and the robotic system is provided.</p>