This standard specifies the type, code, marking, basic parameters, dimensions, technical requirements, inspection rules, packaging and storage of core-type elastic couplings (hereinafter referred to as couplings). This standard is applicable to the coupling of the transmission shaft system connecting two coaxial lines; it has the performance of compensating the relative offset of the two shafts and damping the vibration, the working temperature is -20~+70℃; the nominal torque transmission is 6.3~8000N· m.