This paper presents several heuristic pulse interleaving algorithms for multi-target tracking on pulse Doppler phased array radars that can process multiple simultaneous received beams. A pulse interleaving problem is formalized as a mixedinteger linear program (MILP), explicitly taking into account the constraint that the pulses of different pulse repetition frequencies (PRF) can not be mutually interleaved to prevent pulse eclipsing. Several heuristic pulse interleaving algorithms are developed on the backbone of the same backward interleaving structure, while each algorithm features a PRF selection rule and a task selection rule. Numerical simulations validate effectiveness of the presented heuristic algorithms compared to the optimal solution of the MILP formulation.