Rhombic flexible clamp

The rhombic flexible clamp for SHS treatment of the inner wall of the ultra-long petroleum pipeline comprises a supporting base, a tubular positioning support and rhombic clamps, the supporting base is connected with the tubular positioning support in a sleeved mode, a plurality of positioning grooves are formed in the tubular positioning support, the rhombic clamps are located in the positioning grooves, the two horizontal ends of each rhombic clamp are fixedly connected with the two sides of the corresponding positioning groove, and the rhombic clamps are arranged on the tubular positioning support. The inner side of the rhombic clamp makes contact with the outer wall of the petroleum pipeline so as to fix the petroleum pipeline, the rhombic clamp comprises a guide rod, two movable sleeves, a plurality of connecting rods, anti-skid rolling wheels and springs, the two ends of the guide rod are fixedly connected with the positioning grooves, the movable sleeves are connected with the guide rod in a sleeving m