String saw machine for diamond

The utility model relates to a rope saw for diamond, which is suitable for cutting seafloor single and double layer oil gas pipelines and seafloor pipe frames. The utility model can fix a plurality of diamond grinding heads with a grinding function on a purpose-made rope, and the diamond grinding heads can grind the surfaces to be processed with the directional movement of the rope. The utility model comprises a machine frame, a main cutting system, a feeding system and a fixing device, wherein the machine frame is provided with a frame type structure and the rest three parts are connected into a whole. The main cutting system is composed of an arch support and a piece of diamond rope which passes round a driving wheel, a guide wheel and a tensioning wheel and the main cutting system can accomplish feed motion with the driving of a hydraulic motor and a leading screw. The complete machine is clamped on the pipeline to be processed via the fixing device. When the utility model is used, a water surface service ship can put the complete machine into a seafloor specified position, the utility model can be fixed on the pipeline to be processed by divers' assistance, and the entire working process can be carried out with programming via an operating system.