In industrial organisations, the product development defines a significant part of whole production cost. The Knowledge Management at this stage is a major stake in order to reduce costs and time to market, and also to improve the product quality. Product Lifecycle Management stands as efficient approach to integrate the knowledge management in a company, facing to a several challenge: strong networking of companies, knowledge exchange between companies and knowledge re-use. To reach this objective of PLM based knowledge management, an integrated IT platform is proposed. Named I-Semantec, it is based on Semantic Web technologies, to support knowledge modelling and sharing through the whole product lifecycle.