Integration of process planning and production scheduling is a critical issue to achieving the maximum potential of advanced manufacturing systems. Process planning used to be performed without concurrent considerations on production constraints; hence the resultant plans were vulnerable on shop floor. While many studies attempt to create integration architectures and/or algorithms, little has been done successfully in developing a testbed for examining different integration approaches. This paper presents an object-oriented model for the integration testbed with which different integration algorithms can be examined. Three generic orthogonal OMT models - object model, dynamic model, and functional model - are constructed, and a prototype for the testbed is implemented with object-oriented programming. A simulation study is carried out to examine the effectiveness of several integrated and nonintegrated planning algorithms.