On the basis of general moulding bed for new numerical control adjustable head developed in the early stage, a kind of modular flexible device is proposed to solve the problem that the moulding bed is lack of the travel and transfer convenience in the large-curvature curved surface block construction. The device is composed of connecting mechanism, frame platform, support adjustment module, and moving mechanism. Without changing the pillar specifications of original moulding bed for numerical control adjustable head, the adjustment range of moulding bed can be improved, and its generality and flexibility are better, which is suitable for various curved surface block construction.