In the current dynamic and competitive market, contemporary manufacturing systems must be constantly adapted to meet the requirements for a more agile and smart production. The advent of Industry 4.0 comes as a reference on development of applications and technologies for manufacturing process innovation. Among the pillars of Industry 4.0, a noticeable relevance is given to Cyber Physical Systems, Internet of Things and Internet of Services. In parallel, new technologies as Blockchain and Smart Contracts are important innovations also coined by the Information Technology domain. More specifically, Internet of Services is characterized by a service-oriented computing model enabling a diversity of software-based services through the Internet, among them the Blockchain solution. The paper explores these technologies bringing their intersection as well as their possible applications in the shop floor level. Through the interlock of such concepts, the paper aims to propose an architecture that promotes the utilization of Blockchain for the validation of some service demands in an advanced manufacturing scenario of the Industry 4.0. Lastly a hypothetical case study is presented for illustrating the proposed architecture.