Modern manufacturing has been undergoing significant transformation into the digital era. Advances such as additive manufacturing, biomanufacturing, digital twin, and digital manufacturing bring benefits to manufacturers, but also pose the challenge of transforming planning data using several software tools to accomplish real-time feedback and adjustment for optimal production control and monitoring. Software tools such as CAD, and CAM. PLM, Simulations, ERP, and MOM usually store data in their data models without regard for the semantic meaning of such data. To address interoperability issues researchers have developed ontologies to capture the semantics of data, for example, Industrial Ontology Foundry (IOF) is leading efforts to develop reference ontologies for semantic data integration. This paper reports the results of applying those reference ontologies for data interoperability between CAPP and ERP systems. We have extended reference ontologies to include terms from a domain of plastics manufacturing, particularly process and production planning applications. Domain ontologies are integrated with some domain data of process plans plastic parts from a CAPP systems, and Odoo, an ERP system. We have demonstrated semantic equivalency of those data, though they carry different data model labels. The knowledge graph of ontology and data has been visualized using knowledge graph tool GraphDB. The demonstration serves as a pathway and method for software systems interoperability in industry.